DE69733867T2 - HEADED DISPLAY DEVICE AT THE HEAD - Google Patents

Description

The The present invention relates to a head mounted display device (hereafter referred to as data helmet or HMD (Head Mount Display)) designated) of the one-eyed Type that enlarges an image generated by image display means such that an enlarged virtual Image is obtained, and allows the enlarged virtual See picture with one of the user's eyes.

The Need to observe a display image that is from image display means is shown, simultaneously with a background image has to development eyed by HMDs Type guided. Furthermore is strong with various applications of such single-type HMDs as display devices of computers and as instruction display devices for support calculated by manual controls.

One well-known example for one-eyed such HMDs Type is disclosed in Japanese Patent Laid-Open Publication No. H-2-63379 disclosed. Another example disclosed in Japanese Patent Laid-Open No. H-3-189677 is disclosed as an eyed-type HMD known.

Further examples for Devices for displaying virtual images in combination with a Wallpaper or yourself for one eye or for both Eyes of a user are described in WO 95/11473 A. The claims are shaped by this document.

Of the Data helmet or HMD disclosed in Japanese Patent Laid-Open Publication No. H-3-189677 from the one-eyed See-through type combined by means of a combination device, which is arranged in front of the face, an image bundle, the emitted by an optical system, the side of the face is arranged with a beam of light from the user a background, which superimposes a display image on a background image becomes. In this conventional One-eyed HMD Type is the eye for the observation of the display image as either the left eye or fixed the right eye.

in the Generally people prefer one of their two eyes to one Observe. The size of the post The preferred eye for observing images depends on of the person. The preferred in viewing the display image Eye may vary depending on the nature of the application of the HMD and physical Constitution of the user be different. It is also possible that the user of the HMD problems or disturbances in the view with a Eye has. Consequently, it is impractical, the eye for observation of the display image in the one-eyed type HMD as either left eye or right eye.

A Object of the present invention is therefore, the above solve a problem and an HMD from the one-eyed To create a type that allows the user to select one from a background image and to watch a composite image and a display image without further the eye for to select the observation of the display image.

According to one Aspect of the present invention will be attached to the head Display device as claimed in claim 1.

According to one second aspect of the present invention will be attached to the head Display device as claimed in claim 4.

Around at least partially solving the above objects a head mounted display device according to the preferred embodiment Image display means, magnifying optical Means and switching means. The magnifying optical means are For example, realized as a lens or as a concave mirror and break a first light beam which is incident on the image display means and thereby enlarge the image so that an enlarged virtual Image obtained by the user with one of his two Eyes to watch. The image combining means are for example as a half mirror or a polarizing beam splitter and let the first ray of light, which represents the virtual image, simultaneously with a second one Light beams of a background view into the user's eye, causing the virtual image is combined with the background view to to create a composite image. The switching means relocate the magnifying ones optical means and the image combining means to a change between a first state in which the from the virtual image and the background view composite image with an eye the user is observed, and a second state in which observed the composite image with the other user's eye will do.

The magnifying optical means and the image combining means are arranged so that the first light beam emitted from the image display means passes through the magnifying optical means and the image combining means in that order before reaching the eye of the user. In this case, the magnifying optical means are, for example, as a lens ver unrealized.

In a preferred embodiment Both the image combining means and the magnifying optical means are so arranged that the first light beam, which emitted from the image display means is at least once through the image combining means and the magnifying optical means goes in this order before it is the eye of the User reached. In this case, the magnifying ones optical means, for example, as a concave half mirror or realized as a concave mirror.

The Head mounted display device of the present invention allows the user, one of a background image and a display image composite image either with the left eye or with the right eye to watch. The switching means readily changes the eye for the Observing the composite of the display image and the background Image.

1 illustrates the construction of an optical system of an HMD;

2 shows the appearance of the HMD of 1 ;

3 Fig. 10 illustrates the structure of an optical system in a second embodiment;

4 shows the appearance of the HMD of the second embodiment;

5 Fig. 10 illustrates the structure of an optical system in a first embodiment according to the present invention;

6 Fig. 10 illustrates the structure of a shape converting mechanism in the first embodiment;

7 shows the states of images formed in the first embodiment;

8th Fig. 10 illustrates the structure of an optical system in a second embodiment according to the present invention;

9 Fig. 10 illustrates the structure of a shape converting mechanism in the second embodiment;

10 Fig. 10 illustrates the structure of an optical system in a third embodiment according to the present invention;

11 shows the states of images formed in the third embodiment;

12 shows the appearance of a fourth embodiment according to the present invention;

13 Fig. 10 illustrates the structure of an optical system in a third embodiment;

14 Fig. 10 illustrates the structure of an optical system in a fourth embodiment;

15 Fig. 10 illustrates the structure of an optical system in a fifth embodiment;

16 Fig. 10 illustrates the structure of an optical system in a sixth embodiment;

17 Fig. 10 illustrates the structure of an optical system in a seventh embodiment;

18 Fig. 10 illustrates the structure of an optical system in an eighth embodiment;

19 Fig. 10 illustrates the structure of an optical system in a ninth embodiment;

20 shows the appearance of a fifth embodiment according to the present invention; and

21 Fig. 12 shows a partial transmittance variable transmittance plate and a wiring scheme of its control circuit used in the ninth embodiment.

It Preferred embodiments of the Detailed Description of the Invention with the attached Drawing described.

1 (a) Fig. 12 is a side view illustrating an optical system of a head mounted display device (HMD) in a first embodiment, which is not in accordance with the present invention but will be described for explanation.

1 (b) is a front view of it. 2 shows the appearance of the HMD including the optical system of 1 for the description partly in cross section.

An optical unit 1 as they are in 1 (a) can be placed either in front of the user's left eye or right eye. The optical unit 1 includes a liquid crystal screen 2 of the transmission type, a backlight 3 , a reflex mirror 4 , a condensing lens 5 and a housing 6 in which these components are housed. The liquid crystal screen 2 and the back backlight 3 realize the function of the image display means to display an image in response to image signal output from an external drive circuit, not shown. The Lens 5 realizes the function of magnifying optical means to form a display on the liquid crystal screen 2 is displayed to increase so that an enlarged virtual image is obtained, and to allow a light beam representing the magnified virtual image to enter the eye of the user.

The liquid crystal screen 2 and the backlight 3 are upright in the housing 6 used, so that the normal of an image-forming surface of the liquid crystal screen 2 is oriented substantially in the horizontal direction. The reflex mirror 4 is about the angle of about 45 ° to the normal of the image-forming surface of the liquid crystal panel 2 is tilted and reflects an image beam L1 coming from the liquid crystal panel 2 is emitted vertically downwards. The Lens 5 is arranged so that its optical axis is perpendicular to the normal of the image-forming surface of the liquid crystal panel 2 is. At the bottom of the case 6 is an opening 7 formed, through which the image beam L1 passes. In the opening 7 is a half mirror 8th arranged so that it is at the angle of approximately 45 ° to the optical axis of the lens 5 is inclined.

The upper end of the half mirror 8th is at an in 2 shown main body 14 attached. The transmittance and the reflectance of the half-mirror 8th can be determined arbitrarily; for example, both the transmittance and the reflectance can be set to 50%. The half mirror 8th is so large that it covers the visual field of virtual images for both eyes of the user. The visual field of virtual images is defined by the angle of vision under which the eye sees a virtual image. The half mirror 8th has a recess in its center 9 for the nose of the user. The optical unit 1 , the half mirror 9 and the main body 14 including not shown circuits and other elements are by means of a holder 16 attached to the user's head.

As in 1 (a) is shown, that of the liquid crystal panel 2 generated display image from the back through the backlight 3 is illuminated, and thus the image beam L1 (the first light beam) is radiated from the liquid crystal panel. The image beam L1 is from the reflex mirror 4 deflected by about 90 degrees, from the lens 5 broken and in a ratio corresponding to the transmission / reflection characteristics of the half-mirror 8th corresponds, reflects and produces an image in one eye 10 the user. The image-forming surface of the liquid crystal panel 2 is closer to the lens 5 as a focal point of the lens 5 on the object side, whereas the eye 10 near the other focal point of the lens 5 located on the image page. The imaging function of the lens 5 thus enlarges the display image and generates an enlarged virtual image. The user can thus view the enlarged virtual image of the liquid crystal panel 2 generated display image in an extension of the optical axis 11 that through the eye 10 and the optical unit 1 runs, watch.

The half mirror 8th Reflects a part of the image beam L1, while at the same time a part of a light beam L2 is transmitted from the background view, so that the latter enters both eyes of the user. The half mirror 8th Namely, it functions as the image combining means comprising the first light beam L1, which is the one on the liquid crystal panel 2 displayed image combined with the second light beam L2 from the background view to create a composite image and to allow the composite image to enter an eye of the user. The user can thus observe the image composed of the background image and the display image. As an end of the half-mirror 8th is attached to the main housing, as mentioned above, there is no other obstacle than the main housing arranged above 14 that blocks the user's field of view for the background view. Consequently, this HMD ensures the largest possible field of view for the background. The light beam L2 from the background view, the same half mirror 8th traverses enters both the left and the right eye, so that the left eye and the right eye receive beams of substantially identical luminance. This structure allows the user to naturally observe the background image.

As clearly understood from the above illustration, the term "one-eyed type" in this specification of the invention means that the display image is observed with an eye, even if a part of the optical system of the HMD (e.g., the half-mirror 8th ) includes the field of view corresponding to both eyes, the HMD is still of the "one-eyed type".

In 1 (a) has the optical unit 1 a hollow camp 12 on, behind the reflex mirror 4 is arranged. The inner surface of the warehouse 12 is designed as an internal thread, with an in 2 shown wave 13 in the main body 14 matches. The wave 13 has such a length that it is the main body 14 traverses from one side to the other and both ends of the Hauptge housing 14 be held so that a running of the shaft 18 is possible. At the two ends of the shaft 13 are from both sides of the main body 14 prominent two buttons 15 attached. The warehouse 12 , the wave 13 and the buttons 15 realize the function of the switching means that the optical unit 1 shift to the position in front of the left eye or in front of the right eye. When the user with the hand one of the buttons 15 turns, the shaft moves 13 in relation to the main body 14 , and the optical unit 1 is accordingly shifted to the right or to the left. The optical unit 1 is provided with a rotation stop, not shown, to rotate the optical unit 1 with the rotation of the shaft 13 to prevent. Pressing the button 15 moves the optical unit 1 in essence, over the distance of the user's eyes to between a first state in which the user observes the virtual image with the left eye as in 1 (b) and a second state in which the user observes the virtual image with the right eye. The optical unit 1 can be moved to any arbitrary position substantially over the eye relief. This allows the position adjustment according to the actual eye relief of the user.

As discussed above, this type of see-through type HDM is only the half mirror 8th between the eyes of the user and the background image, so that the user can observe the background image substantially without optical interference. There are except the main body 14 Located above, no obstacle blocking the user's field of view for the background view. This ensures the largest possible field of view for the background view. The user can select either the left or the right eye as the eye watching a virtual image while wearing the HMD on the head. This structure is particularly favorable when multiple users make use of the same HMD. The user can easily switch the eye to observe a virtual image according to the nature of the application of the HMD and its physical condition. The transparency structure allows the user to observe most of the background view images with both eyes. Further, the structure for observing the display image with only one eye does not require any special efforts of the user to combine the images, but allows the user to easily observe the display image only by changing his viewing direction.

When considering the use of eyeglasses with the HMD, it is desirable that the distance between the lens 5 and the eye 10 in 1 (a) is about 60 mm. For enlarging the display image to an enlarged virtual image, it is desirable under such conditions to measure the distance between the liquid crystal panel 2 and the lens 5 as long as possible. The design uses a bending of the light path through the reflex mirror 4 In order to meet both this requirement and the demand for a reduction in the size of the device. The relative positions of the respective components of the liquid crystal panel 2 to the half mirror 8th are not limited to the first embodiment but could be modified in various ways. An exemplary modification leaves the reflex mirror 4 away and arrange the liquid crystal screen 2 face down above the lens 5 at. If the liquid crystal screen 2 located at the front of the HMD, as in 1 (a) For example, one possible modification leaves the backlight, for example 3 eliminates and shapes on the back of the liquid crystal screen 2 a new opening in the case 6 , The extraneous light incident through this opening can illuminate the liquid crystal panel 2 to be used.

The switching means, the bearing 12 , the wave 13 and the buttons 15 are also not limited to the illustrated embodiment but could be modified in various ways. As will be discussed in the following embodiments, the eye-switching switching means for observing a virtual image may use any mechanism that incorporates the magnifying optical means (e.g., the lens 5 ) and the image combining means (for example, the half mirror 8th ) can move.

The above construction may be additionally provided with an actuator mechanism which either displays the liquid crystal panel 2 or the lens 5 in the direction of its optical axis and thereby the relative distance between the liquid crystal screen 2 and the lens. The adjusting mechanism can control the relative distance between the liquid crystal screen 2 and the lens 5 to suit the eyesight of the user, thereby further facilitating the observation of a virtual image.

3 (a) FIG. 11 is a side view illustrating an optical system of another HMD, and FIG (3b) is a front view of it. In this embodiment and the following embodiments, the components that are the same or similar to those of the first embodiment described above are assigned the same reference numerals, and they are not specifically described.

An optical unit 17 as they are in 3 (a) is shown, can be placed either in front of the left eye or in front of the right eye of the user who the. In the example of 3 (b) is the optical unit 17 arranged in front of the left eye. As 3 (a) shows, includes the optical unit 17 the liquid crystal screen 2 , the backlight 3 , the reflex mirror 4 , the Lens 5 , a half mirror 18 and a housing 19 in which these components are housed. The relative positions of the liquid crystal screen 2 , the backlight 3 , the reflex mirror 4 , the lens 5 and the half mirror 18 are identical to those of the first embodiment. The half mirror 18 has the same reflection / transmission behavior as the half mirror 8th of the first embodiment. As in 3 (b) however, the half mirror is shown 18 a size that covers the visual field of a virtual image for only one eye of the user.

As in 3 (a) is shown, the housing has 19 a substantially trapezoidal side elevation and is with an opening 20 provided, which is formed in its vertical surface so as to the eye 10 the user is facing. Another opening 21 is in the inclined surface of the housing 19 formed, wherein the half-mirror 18 is arranged. The second embodiment differs from the first embodiment in that the half mirror 18 together with other optical elements in the optical unit 17 is arranged. The optical unit 17 is with the main body 14 by means of the same construction as those of 2 shown first embodiment in engagement.

4 shows the look of the HMD.

The only difference to the first execution, the in 2 is shown that the half mirror 18 for just one eye into the optical unit ( 17 ) is integrated.

As in 3 (a) is shown, that of the liquid crystal panel 2 radiated image beam L1 combined with the background beam L2 and enters the eye 10 a, on which the optical unit 17 is arranged. Part of the background beam L2 is from the half mirror 18 reflected, and only the rest enters the eye 10 one. As in 3 (b) On the other hand, there is no half-mirror 18 in front of the eye, on which the optical unit 17 is not arranged. The background beam L2 thus enters the eye unimpaired, which does not observe the virtual image. Thus, in the HMD of the second embodiment, the brightness of the background image observed with the left eye is significantly different from that observed with the right eye. It is generally the case that the difference in brightness between the left eye and the right eye of not less than 70% causes a conflict of visual fields and makes the viewing of both images very stressful. On the other hand, a brightness difference of not more than 30% between the visual fields of the left eye and the right eye ensures safe observation for a relatively long time. In the second embodiment, the transmission / reflection behavior of the half mirror is 18 adequately adjusted so as not to make the difference in brightness between the visual fields of the left eye and the right eye greater than approximately 30%, so that it is easier to observe the background view. In fact, the reflectance and transmittance of the half mirror become 18 set to about 30% and 70%, respectively. Such a setting enables the brightness difference between the background images observed with the left eye and the right eye to be about 30%. However, the extremely high transmittance prevents reflection of the image beam L1. Consequently, it is desirable to make the reflectance as high as possible to make the display image brighter.

The switching means for changing the eye for observing a virtual image has a structure similar to that of the first embodiment except that the half mirror 18 the second embodiment with the optical unit 17 joined together and moves with the other optical elements from one side to the other, whereas the half mirror 8th the first embodiment is fixed. The function of the switching means in the second embodiment is identical to that in the first embodiment. Turning either the left button or the right button 15 moves the optical unit 17 essentially across the eye relief of the user to between a first state in which the user observes a virtual image with his left eye, as in 3 (b) and a second state in which the user observes a virtual image with the right eye. In the second embodiment stops the simultaneous movement of the liquid crystal screen 2 , the lens 5 and the half mirror 18 the fixed positional relationships between these three optical elements upright. This advantageously ensures the more stable performance of the optical system incorporating these optical elements. Consequently, the second embodiment further reduces the restrictions on the positioning of the optical system with respect to the user's eye and increases the degree of freedom of positioning. Furthermore, the size of the entire device can be reduced since the half mirror 18 the minimum required size and with the optical unit 17 is integrated, with the possibility of damage to the half-mirror 18 is low.

C. First Embodiment

5 (a) is a side view, which is an opti shows still another HMD system as a first embodiment according to the present invention; 5 (b) Fig. 10 is a front view showing a first state in which the user observes a virtual image with the left eye, 5 (c) illustrates a switching mechanism to switch the eye for the observation of a virtual image, and 5 (d) Fig. 16 is a front view showing a second state in which the user observes a virtual image with the right eye.

How out 5 (a) is apparent, in this optical system, a reflection unit 50 and an optical unit 28 under the liquid crystal screen 2 arranged.

The optical unit 28 includes a lens 26 , the half mirror 18 and a housing 27 in which these components are housed. As in 5 (a) is shown, the housing has 27 a substantially trapezoidal side elevation and is with an opening 29 provided, which is formed in its vertical surface so as to the eye 10 the user is facing. Another opening 30 is in the inclined surface of the housing 27 formed, wherein the half-mirror 18 is arranged.

How out 5 (b) is visible, contains the reflection unit 50 two reflex mirrors 23 and 24 which are arranged substantially parallel to each other, and two connecting members 25a and 25b to the two reflex mirrors 23 and 24 to connect with each other. The connecting links 25a and 25b connect the upper ends and the lower ends of the two reflecting mirrors 23 and 24 such that a parallelogram is formed. Even if the parallelogram of the reflection unit 50 is deformed, this structure allows the two reflecting mirrors 23 and 24 to keep substantially parallel to each other. In the first state of 5 (c) and in the second state of 5 (d) are the two reflex mirrors 23 . 24 each at the angle of about 45 ° to the normal of the display area of the liquid crystal panel 2 inclined.

If the user observes a virtual image with the left eye as in 5 (c) is shown, the image beam L1 from the liquid crystal screen 2 first from the first reflex mirror 23 and then from the second reflex mirror 24 reflected. On the other hand, when the user observes a virtual image with the right eye as in 5 (d) is shown, the image beam L1 from the liquid crystal screen 2 first from the second reflex mirror 24 and then from the first reflex mirror 23 reflected. That of these two reflex mirrors 23 and 24 deflected image beam L1 then enters the lower optical unit 28 one. The reflection unit 50 Consequently, the function of reflection means which reflect the image beam L1, or the function of deflection means which deflect the image beam bundle L1.

6 Fig. 10 illustrates a shape converting mechanism for changing the shape of the reflection unit 50 during a movement of the optical unit 28 , In the back wall of the optical unit 28 are two pens 51a and 51b educated. The second link 25b has two matching elements at its lower end 52a and 52b on. These matching elements 52a and 52b each have slots that extend in the vertical direction. The two pens 51a and 51b the optical unit 28 traverse the slots of the two engaging parts 52a and 52b of the connecting link 25b and are slidable in a groove 53 placed in the main body 14 is formed (see 2 ). The two reflex mirrors 23 and 24 have pens 55a and 55b on, which are arranged in their respective centers. These pens 55a and 55b are slidable in another groove 54 placed in the main body 14 is trained. In the presentation of 6 are for practical reasons the grooves 53 and 54 filled with oblique lines to clearly distinguish them from the other components.

The user moves the reflection unit 50 and the optical unit 28 in the horizontal direction, to move between the first state, the in 5 (c) is shown, and the second state, in 5 (d) shown is to switch. A comparison of 5 (c) and 5 (d) shows that the liquid crystal screen 2 and the backlight 3 face down on a centerline 22 the width of the device are arranged, and are not displaced by the change of the eye for the observation of a virtual image.

5 (b) shows the state halfway a change from the first state, which in 5 (c) is shown in the second state, in 5 (d) is shown. In the state of 5 (c) is the shape converter mechanism of the reflection unit 50 to the position of 6 set. When a force in the direction of an arrow A on the optical unit 28 in the state of 6 is exercised, moves the optical unit 28 the groove 53 along (see 6 ) to the right eye (in 6 to the left), and the reflection unit 50 Accordingly, the groove moves 54 along. At this time, the reflection unit retains 50 essentially the parallelogram shape of 5 (b) at, although they are with the optical unit 28 emotional. If the pen 55a (please refer 6 ), which is essentially in the center of the reflex mirror 23 is arranged, one end of the groove 54 reached, the parallelogram of the reflection unit 50 gradually over the state of 5 (b) in the state of 5 (d) deformed while the two pins 55a and 55b be held at their positions. The optical unit 28 is moving Accordingly, in the position opposite to the right eye to effect the second state, which in 5 (d) is shown. Reverse manipulations and movements are performed to change the eye for observing a virtual image from the right eye to the left eye.

In the first state of 5 (b) and in the second state of 5 (d) are the reflection unit 50 and the optical unit 28 by means of a known mechanical positioning mechanism, such as a combination of pins and engagement holes.

It is a variety of structures other than those discussed above for the reflection unit 50 and its shape conversion mechanism applicable. For example, the shape of the reflection unit 50 be changed while the upper link 25a continue to the liquid crystal screen 2 opposite and the lower link 25b continue the lens 26 opposite. As long as the two in 5 (b) and 5 (d) shown states realized who can, is neither the transition state nor the movement of the reflection unit 50 important.

7 shows that the user is a virtual image in the same direction in both the first state of 5 (b) as well as in the second state of 5 (d) can watch. 7 (a) shows the first state in which the user observes a virtual image with the left eye, whereas (7b) represents the second state in which the user observes a virtual image with the right eye. In these sketches, the arrows drawn near the respective optical elements give a first direction 61 indicative of a first coordinate axis of the image forming surface of the liquid crystal panel 2 equivalent. The circled crosses give a second direction 62 which corresponds to a second coordinate axis of the image-forming surface. The second direction 62 runs from the front to the back of the drawing sheet. The arrows showing these directions 61 and 62 represent are on the half mirror 18 drawn. How out 7 (a) and 7 (b) is clearly visible on the liquid crystal screen 2 The image produced is reflected three times and observed with either the left eye or the right eye as an image with the same orientation. Consequently, when changing the eye to observe a virtual image, no electrical switching operation with respect to the direction of display of the image is required.

As discussed above, the first embodiment may switch the eye for the observation of a virtual image while the liquid crystal display screen 2 and the backlight 3 stay in a fixed position. Because the liquid crystal screen 2 and the backlight 3 are conductively connected to a drive circuit is preferable for the electrical safety that no shift of the liquid crystal screen 2 and the backlight 3 occurs. In other words, the first embodiment ensures the high electrical reliability in the process of changing the eye for the observation of a virtual image.

In the first embodiment, the position of the liquid crystal panel 2 is fixed, the position setting of the optical unit 28 in the horizontal direction, according to the actual eye distance of the user, the relative distance between the liquid crystal panel 2 and the lens 26 change. This results in a change in the distance from the user's eye to a virtual image. To avoid this problem could be during a movement of the optical unit 28 either the liquid crystal screen 2 or the lens 26 along its optical axis, thereby keeping the distance from the user's eye to a virtual image. Another possible structure is the extension of the exit pupil of the lens 26 while the position of the optical unit 28 is held either in front of the left eye or in front of the right eye, so that an individual difference in eye relief is absorbed.

D. Second Embodiment

8 (a) Fig. 10 is a side view showing an optical system of another HMD as a second embodiment according to the present invention; 8 (b) Fig. 10 is a front view showing a first state in which the user observes a virtual image with the left eye in the second embodiment; and 8 (c) Fig. 16 is a front view showing a second state in which the user observes a virtual image with the right eye.

This in 8a shown optical system comprises another reflection unit 70 instead of the reflection unit 50 the first embodiment, which in 5a is shown. As in 8 (b) and 8 (c) is shown, the reflection unit 70 three reflex mirrors 31 to 33 on. The first reflex mirror is on the midline 22 the eye distance arranged. The second reflex mirror 32 and the third reflex mirror 33 are slightly above the left eye or the right eye, and in front of them are arranged so that they are in relation to the midline 22 are symmetrical. The second and the third reflex mirror, 32 and 33 , are each about the angle of about 45 Degree inclined to the vertical.

The first reflex mirror 31 is either in Direction of an arrow C in 8 (b) or in the direction of an arrow D in 8 (c) around the axis of rotation, on the center line 22 is arranged, rotatable. The rotation alternates between the two states of 8 (b) and 8 (c) , In the first state of 8 (b) reflects the first reflex mirror 31 the image beam L1 in the direction of the second reflection mirror 32 , and that of the second reflex mirror 32 Reflected light beam enters the optical unit 28 one. On the other hand, in the second state of 8 (c) the first reflex mirror 31 the image beam L1 in the direction of the third reflection mirror 33 , and that of the third reflex mirror 33 Reflected light beam enters the optical unit 28 one. The angle of rotation of the reflex mirror 31 for a change between the states of 8 (b) and 8 (c) can be 90 ° if both surfaces of the first mirror 31 are designed as mirror planes or when the direction of rotation of the reflecting mirror 31 is reversible.

9 shows a shape converter mechanism to the reflex mirror 31 during a movement of the optical unit 28 to turn. In this example, the reflex mirror points 31 mirror planes on both surfaces. The physical center of the reflex mirror 31 is by means of a support pin 71 in the main body 14 is arranged (see 4 ), rotatably mounted. Another pen 72 is at the lower end of the reflex mirror 31 arranged. This pen 72 is displaceable in a guide groove 73 placed in the back wall of the optical unit 28 is trained. The guide groove 72 extends in a horizontal direction, and the pin 72 becomes along the guide groove 13 guided so that it is movable in the horizontal direction. Because turning the reflex mirror 31 the vertical position of the pen 72 changed, has the leadership 73 in the vertical direction an extension that is the area of the vertical position of the pen 72 covers. The optical unit 28 is displaceable by means of a pin, not shown, in a groove 74 inserted in the main body 14 is trained.

In the first state in 8 (b) is the form converter mechanism to the position of 9 set. When in the state of 9 a force in the direction of an arrow A on the optical unit 28 is exercised, this moves the groove 74 along. In the initial stage of the movement is the pen 72 in the guide groove 73 released, which has the consequence that the reflex mirror 31 not turned. Moving the optical unit 28 causes the pen 72 against the end portion of the guide groove 73 is pressed, and the force coming from the optical unit 28 is exercised, turns the first reflex mirror 31 in the direction of arrow C. The optical unit 28 thus moves to the position in front of the right eye to realize the second state, which in 8 (c) is shown. The reflection direction of the first reflection mirror 31 is changed from "to the left" to "to the right". As discussed in the first embodiment, the user can observe a virtual image in the same direction in both the first state and the second state. Inverse manipulations and movements are performed to switch the eye for the observation of a virtual image from the right eye to the left eye.

As discussed above has been the second embodiment the same effects as the first embodiment and simplified Further, the deformation mechanism of the reflection unit (i.e. Formwandlermechanismus), whereby the structure of the switching means, around the eye for to change the observation of a virtual image, simplified. On the other hand needed discussed above first embodiment in comparison with this second embodiment in an advantageous Make the smaller number of reflex mirrors in the reflection unit.

E. Third Embodiment

10 (a) Fig. 12 is a side view showing an optical system of still another HMD as a third embodiment according to the present invention; 10 (b) Fig. 10 is a front view showing a first state in which the user observes a virtual image with the left eye in the third embodiment; and 10 (c) Fig. 16 is a front view showing a second state in which the user observes a virtual image with the right eye.

This in 10 (a) to 10 (c) The optical system shown has the liquid crystal panel 2 and the backlight 3 located at positions different from those in the optical system of 8 (a) shown second embodiment, and has another reflection unit 80 instead of the reflection unit 70 on. As in 10 (b) and 10 (c) shown are the liquid crystal panel 2 and the backlight 3 near the midline 22 of the eye distance arranged around the normal of the image-forming surface of the liquid crystal panel 2 to extend substantially in the horizontal direction. The reflection unit 80 contains two reflex mirrors 34 and 35 that are in relation to the midline 22 are arranged symmetrically. The two reflex mirrors 34 and 35 are each at the angle of about 45 degrees to the normal of the display area of the liquid crystal panel 2 tilt and deflect the image beam L1 substantially horizontally from the liquid crystal panel 2 is radiated, vertically downwards.

In the third embodiment, the liquid crystal panel 2 and the backlight 3 held so that they are rotatable as a whole. A turning of the liquid crystal screen 2 and the backlight 3 changes the current state between the first state, the in 10 (b) is shown, and the second state, in 10 (c) is shown. The rotation axis of the liquid crystal screen 2 coincides with the optical axis passing through the center of the image-forming surface of the liquid crystal panel 2 runs. This allows the distances from the image-forming surface of the liquid crystal panel 2 to the two reflex mirrors 34 and 35 are completely the same in both the first state and in the second state.

When a force in the direction of an arrow A on the optical unit 28 in the first state of 10 (b) is exercised, moves the optical unit 28 along a rail, not shown, between the optical unit 28 and the reflection unit 80 is arranged. During the course of the movement, the force rotating from the optics unit rotates 28 is exercised, the liquid crystal panel 2 and the backlight 3 overall in the direction of an arrow E, leaving the second state in 10 (c) is shown, is realized. The direction of the image beam L1 coming from the liquid crystal panel 2 namely, changes from "to the left" to "to the right", and hence the image beam L1 from the first reflecting mirror 35 reflected down and enters the optical unit 28 one. Inverted manipulations and movements are performed to change the eye for observing a virtual image from the right eye to the left eye.

11 shows the fact that the user has a virtual image with the same orientation in both the first state of 10 (b) as well as in the second state of 10 (d) can observe and corresponds 7 the first embodiment. The first direction 61 corresponds to the first coordinate axis of the image-forming surface of the liquid crystal panel 2 while the second direction 62 corresponds to the second coordinate axis of the image-forming surface. How out 11 (a) and 11 (b) clearly recognizable, every image that appears on the liquid crystal screen 2 is generated, reflected twice and observed with either the left eye or the right eye as an image with the same orientation. In this structure, when the eye is changed to observe a virtual image, no electrical switching operation is required with respect to the orientation of the display image.

As discussed above in the third embodiment, only the lens becomes 26 and the half mirror 18 moved substantially beyond the eye relief of the user to the direction of the radiation of the image beam L1 from the liquid crystal screen 2 which changes the eye for observing a virtual image. This simplifies the structure of the reflection unit. The realization of the in the reflection unit 80 housed liquid crystal screen 2 effectively reduces the size of the device.

F. Fourth Embodiment

12 shows the appearance of another HMD as a fourth embodiment according to the present invention. The in 12 The HMD shown has any of the optical systems discussed in the first to third embodiments. The difference to the HMD of the 4 the second embodiment shown is that the HMD of in 12 shown fourth embodiment, a partially transparent screen plate 37 which has substantially the same transmittance as the half mirror 18 and located in front of the eye, which does not see the virtual image. The partially translucent screen plate is detachable on the main body 14 attached and can be placed in front of one of the user's eyes, in front of the left eye or right eye. The user takes the partially translucent screen plate 37 from the main body 14 and moves the optical unit 17 (or 28 ) to switch the eye for observing a virtual image. The partially translucent screen plate 37 then gets back to the main body 14 attached so that it is in front of the eye that does not see a virtual image.

Preferably, the transmittance of the partially transparent screen plate 37 adjusted so that it is the transmittance of the half mirror 18 is essentially the same. For example, as discussed in the second embodiment, the brightness difference between the left and right visual fields should preferably not be greater than 30%. Adjusting the transmittance of the partially transparent screen plate 37 in the range of about 0.7 times to 1.3 times the transmittance of the half mirror 18 allows the brightness of the background image, through the half-mirror 18 is observed, essentially with the brightness of the background image passing through the partially translucent screen plate 37 observed matches. The user can therefore observe the background image in a natural way. This design places less stringent requirements on the transmission / reflection behavior of the half-mirror 18 as that of the second embodiment, and setting this behavior allows the brightness relationship between the on set the picture and the background picture arbitrarily.

G. Third order

13 (a) Fig. 12 is a side view showing an optical system of another HMD as a third arrangement. An in 13 (a) shown optical unit 38 has a polarizing beam splitter 39 instead of the half mirror 18 on that in the optics unit 17 the in 3 shown second embodiment, and further includes a partially transparent screen plate 40 with polarization selectivity in front of the polarizing beam splitter 39 , In this specification, the term "polarization selectivity" means the property of transmitting or reflecting a specific polarized light component.

The liquid crystal screen 2 has polarizing plates (not shown) on its light-receiving surface and its light-emitting surface. In the third arrangement, the image beam L1 is that of the liquid crystal panel 2 is emitted, s-polarized light whose plane of oscillation perpendicular to the light-receiving surfaces of the reflecting mirror 4 and the polarizing beam splitter 39 is (ie the plane is parallel to the leaf surface). In the sketches of 13 For example, each free circle with a black dot drawn in the vicinity of a luminous flux indicates that the luminous flux is s-polarized light. On the other hand, each line segment with two arrows indicates that the luminous flux is p-polarized light.

The polarizing beam splitter 39 has the property of reflecting the s-polarized light while transmitting the p-polarized light whose vibration plane is perpendicular to that of the s-polarized light. The polarizing beam splitter 39 is so large that it covers the field of view of a virtual image for only one eye of the user. In again 2 shown mirrors 8th has the partially translucent screen plate 40 such a size and shape that it covers the visual field of virtual images for both eyes of the user. The partially translucent screen plate 40 For example, it consists of a polarizing plate and behaves so as to selectively pass only the p-polarized light.

As in 13 (a) is shown, that of the liquid crystal panel 2 generated image from the back by means of the backlight 3 is illuminated, and accordingly, the image beam L1 s-polarized light is emitted. After a change of direction of the beam path by about 90 degrees through the reflex mirror 4 the image beam L1 is transmitted through the lens 5 Broken. The image beam L1 s-polarized light is received by the polarizing beam splitter 39 reflected to almost 100% and produces an image in the eye 10 the user.

On the other hand, the backlight beam L2 is non-polarized light containing p-polarized light and s-polarized light. The partially translucent screen plate 40 leaves only the p-polarized light component of the background beam L2, and then the p-polarized light enters the polarizing beam splitter 39 one. The polarizing beam splitter 39 has the property that it transmits the p-polarized light to almost 100% and thus outputs the p-polarized light component of the backlight beam L2 without substantial reflection or absorption. Namely, almost 100% of the p-polarized light component of the light beam L2 from the background view reaches the user's eye observing a virtual image. As a result, the s-polarized light image beam L1 and the p-polarized light backlight L2 simultaneously enter the eye observing a virtual image. The user can thus observe a composite image, ie a combination of the display image with the background image.

13 (b) shows the state in which the partially translucent screen plate 40 placed in front of the eye, which does not see a virtual image.

These Configuration allows that almost 100% of the p-polarized light component of the light beam L2 enters the eye from the background, not a virtual image sees.

In the third arrangement, the main part of the image beam L1 becomes the liquid crystal panel 2 through the polarizing beam splitter 39 reflects and enters the eye 10 one. This significantly improves the brightness of the display image observed by the user. Since the brightness of the background image that penetrates the eye that sees a virtual image substantially matches the brightness of the background image that penetrates the eye that does not see a virtual image, the user can naturally observe the background image. Since the third arrangement allows the left eye and the right eye of the user to see the background images with substantially the same brightness as in the fourth embodiment, the degree of freedom in brightness of the display image and the background image is remarkably improved. More specifically, adjusting the transmission / reflection performance of the partially transparent screen plate 40 allows the brightness relationship between the display image and the background image arbitrarily set. As the partially translucent screen plate 40 outside the polarizing beam splitter 39 arranged and fixed to the main body, having such a size as to cover the visual field of a virtual image for both eyes of the user, it does not affect the switching operation to change the eye for observing a virtual image ,

The polarizing beam splitter 39 and the partially translucent screen plate 40 The third arrangement is not limited to the realization of the optical system discussed in the second embodiment, but is also applicable to the other embodiments of the optical system discussed in the first to third embodiments.

As from the discussion of the third arrangement, the image combining means, the image bundle L1 with the background beam L2 combine, through a variety of semitransparent mirrors, such as a half-mirror, and a polarizing beam splitter be realized. The semitransparent mirrors close here not just those with a polarization selectivity such as a polarized one Beam splitter, but also those without polarization selectivity, such as a half mirror.

The partially translucent Sieve plate, which is arranged in front of the eye, that no virtual Picture can look a bit pervious Element with polarization selectivity or a semipermeable element without polarization selectivity be.

The Image combining means used in the third arrangement include the polarizing beam splitter that allows that the image beam L1 enters the user's eye without the amount of light is significantly reduced. Because the polarizing plate, the one has such size, that it covers the field of view of a virtual image for both eyes, as partially translucent Screen plate is used, the user can change the background image regardless of which eye for the viewing of a virtual image is selected to be in good harmony with watch the display image.

H. Fourth arrangement

14 Fig. 10 illustrates the structure of an optical system of still another HMD as a fourth arrangement. An optical unit 90 includes the liquid crystal screen 2 , the backlight 3 , the half mirror 18 , a concave half mirror 92 and a housing 94 in which these components are housed. The concave half mirror 92 is arranged so that it the user beyond the level half mirror 18 opposite. The concave half mirror 92 is used instead of the lens as magnifying optical means. The mechanism for moving the optical system in this embodiment may be the same as the mechanism in the second embodiment or that in the third arrangement, and hence will not be specifically described here.

The liquid crystal screen 2 is face down over the flat half mirror 18 arranged. Part of the from the liquid crystal screen 2 emitted image beam L1 is from the plane half mirror 18 reflected so that it is in the direction of the concave half mirror 92 is distracted. The image beam L1 is then emitted from the inner surface of the concave half mirror 92 reflects and crosses the plane half mirror 18 to get into the eye 10 of the user. Since the inner surface of the concave half mirror forms a concavity, the image represented by the image beam L1 reflected from the concavity is magnified as a virtual image which is observed.

On the other hand, a part of the backlight beam L2 passes through the concave half mirror 92 and the flat half mirror 18 to get into the eye 10 of the user. The concave half mirror 92 has a uniform thickness and thus transmits most of the light beam L2 from the background without refraction. The user can thus view the intact background image with the enlarged virtual image of the display image displayed on the liquid crystal display screen 2 is displayed, watch.

The fourth arrangement has no lenses between the liquid crystal panel 2 and the flat half mirror 18 , reducing the distance between the liquid crystal screen 2 and the flat half mirror 18 can be reduced.

These Configuration effectively reduces the size of the whole optical system. Furthermore reduces the use of the concave mirror instead of the lens the aberrations.

I. Fifth arrangement

15 Fig. 10 illustrates the structure of an optical system of another HMD as a fifth arrangement. An optical unit 95 has the concave half mirror 92 disposed at a position different from that in the eighth embodiment shown in FIG 14 is shown, is different, and further includes a partially transparent screen plate 96 , The concave half mirror 92 is arranged so that it is the liquid crystal screen 2 beyond the level half mirror 18 opposite. The partially light through casual screen plate 96 is arranged so that it the user beyond the level half mirror 18 opposite.

A part of the image beam L1 coming from the liquid crystal panel 2 is radiated, passes through the flat half mirror 18 , is from the inner surface of the concave half mirror 92 reflected and from the plane half mirror 18 reflected again to the eye 10 of the user. The concave half mirror 92 has, as in the eighth embodiment, the in 14 is shown, the function of magnifying optical means.

On the other hand, a part of the backlight beam L2 traverses the partially transparent screen plate 96 and the flat half mirror 18 to get into the eye 10 of the user.

Like the fourth arrangement, the in 14 is shown, the fifth arrangement has the advantages that the size of the entire optical system is reduced and the aberrations are reduced. An additional advantage of the fifth arrangement is that by adjusting the transmittance of the partially transparent screen plate 96 the brightness of the background image can be controlled. For example, adjusting the transmittance of the partially transparent screen plate improves 96 to a relatively high value the brightness of the background image.

The partially translucent screen plate 96 shields a part of the background beam L2, which accordingly the proportion of the background beam L2, that of the half mirror 18 is reflected to the liquid crystal screen 2 to get, reduced. This causes the glare on the surface of the liquid crystal panel 2 reduced.

Instead of the concave half mirror 92 a concave mirror could be used. The concave mirror has a higher reflectance than the concave half mirror and thus improves the brightness of the eye 10 observed display image.

J. Sixth order

16 (a) Fig. 11 illustrates the structure of an optical system of still another HMD as a sixth arrangement. An optical unit 97 contains the liquid crystal screen 2 , the backlight 3 , the half mirror 18 , a magnifying optical system 98 of the type with internal reflection and a housing 99 in which these components are housed.

The magnifying optical system 98 of the type with internal reflection is between the half mirror 18 and the user inserted. Part of the from the liquid crystal screen 2 emitted image beam L1 is from the half mirror 18 reflected in the direction of the user and enters the magnifying optical system 98 of the type with internal reflection.

The magnifying optical system 98 The internal reflection type is generally referred to as a "pancake window", which has the function of optically magnifying an image by repeated internal reflection of light, the structure and function of the magnifying optical system 98 internal reflection type are described in U.S. Reissue Patent No. 27,356.

16 (b) Fig. 10 is a disassembled perspective view showing the internal reflection type magnifying optical system described in US Reissue Patent No. 27,356. The magnifying optical system 98 of the internal reflection type contains a concave half mirror 100 , a first λ / 4 plate 102 , a level half mirror 104 , a second λ / 4 plate 106 and a polarizing plate 108 which are superimposed in this order. How out 16 (a) it can be clearly seen, the distances between the respective optical elements in the magnifying optical system 98 of type with internal reflection in 16 (b) exaggerated to clarify the beam path.

That from the flat half mirror 18 reflected image beams L1 enters the concave half mirror 100 , In the sketch of 16 (b) the line segment with two arrows indicates the vibration direction of the vibration vector of the linearly polarized light, and the spiral indicates the rotational direction of the vibration vector of the circularly polarized light.

Since a polarizing plate on the light-emitting surface of the liquid crystal panel 2 is disposed, the image beam L1, which is in the concave half mirror 100 enters, linearly polarized light. The image beam L1 passes through the concave half mirror 100 and is from the first λ / 4 plate 102 converted into circularly polarized light. The image beam L1 of circularly polarized light is converted into a first luminous flux L1a, which is the plane half mirror 104 traverses, and a second luminous flux L1b, of the plane half mirror 104 reflected, shared. The first luminous flux L1a is from the second λ / 4 plate 106 converted into linearly polarized light. The vibration direction of the vibration vector of this linearly polarized light is perpendicular to the vibration direction of the original image beam L1. The first luminous flux L1a, that of the second λ / 4 plate 106 is issued by the polarizing plate 108 shielded and does not reach the eye 10 the user. The polarizing plate 108 selectively passes the linearly polarized light whose direction of oscillation to that of the image beam L1, that in the concave half mirror 100 is completely equal, while the linearly polarized light whose vibration direction is perpendicular to that of the image beam L1 is shielded.

On the other hand, after passing from the plane half mirror, the second luminous flux L1b passes through 104 has been reflected, again the first λ / 4 plate 102 to be converted into linearly polarized light, and becomes from the inner surface of the concave half mirror 100 reflected. The vibration direction of the vibration vector of the second luminous flux L1b is perpendicular to the vibration direction of the image beam L1, that of the outside into the concave half mirror 100 arrives. The second luminous flux L1b undergoes refraction when coming from the concave half mirror 100 is reflected. Thereby, the display image is enlarged so that an enlarged virtual image is obtained.

The from the inner surface of the concave half mirror 100 reflected second luminous flux L1b is by means of the first λ / 4 plate 102 again transferred into circularly polarized light and enters the plane half mirror 104 one. The plane half mirror 104 traversing second luminous flux L1b is by means of the second λ / 4 plate 106 converted into linearly polarized light. The second luminous flux L1b passing through the second λ / 4 plate 106 passes through, passes through the polarizing plate 108 and reaches the eye 10 the user. Since the second luminous flux L1b generates an enlarged virtual image when viewed from the inner surface of the concave half mirror 100 is reflected, the user can observe the magnified virtual image.

In addition to the second luminous flux L1b, the in 16 (b) As shown, there are light fluxes that repeat a greater number of internal reflections before entering the user's eye. However, such further luminous fluxes are due to the loss, mainly in the half-mirrors 100 and 104 , a much smaller amount of light than the second luminous flux L1b. The effects of these further luminous fluxes entering the user's eye are therefore irrelevant.

The background beam L2 contains randomly polarized light components, the polarized light component of the background beam L2 crossing the image beam L1, the respective optical elements in the magnifying optical system 98 traverses the type with internal reflection and the eye 10 reached by the user. The user thus observes the intact background image which is not subject to enlargement to an enlarged virtual image. A part of the background light beam L2 follows a light path corresponding to that in 16 (b) shown light path of the first luminous flux L1b is identical, and generates an image near the eye 10 , Since the light source of the background beam L2 is generally far from the focal point of the concave half mirror 100 is removed, however, the location of the image formation is closer to the eye than the near point of the eye (ie, the closest place where the eyes can see an object in focus). The user thus does not perceive the enlarged virtual image of the background view.

When another type of image display means emitting a light beam which is non-linearly polarized light is used instead of the liquid crystal panel 2 A polarizing plate can be used on the light receiving surface of the 16 (b) shown concave half mirror 100 be arranged.

As the fourth and the fifth Arrangement, the sixth arrangement effectively reduces the size of the entire optical system and reduces the aberrations.

In the fourth to sixth arrangements with the concave mirror, the plane half mirror can 18 have a size that covers the visual field of the virtual images for both eyes. Further, any of the structures discussed in the first and second embodiments and in the first to third embodiments is applicable to the switching means for changing the eye for observation of a virtual image in the fourth to sixth arrangements.

K. Seventh arrangement

17 (a) Fig. 12 illustrates the structure of an optical system of another HMD as a seventh arrangement. An optical system 109 includes in addition to the optical unit 90 the in 14 shown fourth arrangement, the elements described below. A partially translucent screen plate 110 is in front of the concave half mirror 92 arranged. The upper end of the partially translucent screen plate 110 is with a first rack 112 connected while the top of the case 94 the optical unit with a second rack 114 connected is. This in 14 shown bearings 12 omitted in the optical system 109 from 17 ,

17 (b) is a two-dimensional view of this optical system 109 shows. In the opposite surfaces of the two racks 112 and 114 are formed teeth. Between the two racks 112 and 114 is a rite zel 116 inserted, and the teeth of the pinion 116 arrive with the teeth of the two racks 112 and 114 engaged. As 17 (a) shows is over the pinion 116 a button 118 arranged, which allows the pinion 116 to turn.

In this seventh arrangement, the main body 14 and the holder 16 , in the 12 shown are used. The two racks 112 and 114 are slidably movable, being guided by grooves, not shown, in the main housing 14 are formed. As in 17 (b) shown are the two racks 112 and 114 flexible and run along the grooves of the main housing 14 where they are curved.

The pinion 116 is from the main body 14 so kept that running a pinion 116 is possible. When the user clicks on the button 118 turns, the two racks move 112 and 114 during a rotary movement of the pinion 116 in opposite directions. Like now again 17 (b) can be seen, are the optical unit 109 and the partially translucent screen plate 110 arranged so that they are in relation to a center line 120 are substantially symmetrical. The movements of the two racks 112 and 114 thus shift the optical unit 109 and the partially translucent plate 110 in opposite directions while maintaining the substantially symmetrical relationship. The user can press the button 118 the optical unit 109 and the partially translucent screen plate 110 set to suitable positions that correspond to his eye relief. Because the two racks 112 and 114 Move without disturbing each other, the horizontal positions of the optical unit 109 and the partially translucent screen plate 110 by pressing the button 118 it will be exchanged.

As discussed above, the seventh arrangement has the mechanism for displacing the optical unit 109 and the partially translucent screen plate 110 in opposite directions while maintaining the substantially symmetrical relationship thereof. Consequently, this structure requires no operation for removing the partially transparent screen plate 110 when changing the eye for the observation of a virtual image. In addition, this structure advantageously facilitates the position adjustment according to the eye relief of the user. This displacement mechanism is applicable not only in the case where the concave half mirror is used as the magnifying optical system, but also in the case where the lens is used as the magnifying optical system (for example, the second arrangement shown in FIG 3 and 4 shown) is used. Even if the optical system is not the partially translucent screen plate 110 includes, is in 17 shown displacing mechanism can be used as a switching means to shift the optical unit in the horizontal direction and to switch the eye for the observation of a virtual image.

L. Eighth arrangement

18 (a) Fig. 12 illustrates the structure of an optical system of still another HMD as an eighth arrangement. This optical system comprises an optical unit 130 , the optical unit 95 the in 15 shown seventh embodiment is almost the same, but not the partially translucent screen plate 96 for only one eye, but a partially translucent screen plate 132 for both eyes. The partially translucent screen plate 132 is removable in a groove 134 inserted, which is formed in a main housing. The groove 134 is for example in the in 12 shown main body 14 educated.

18 (b) Fig. 16 is a front view showing the optical system of the eighth arrangement. The partially translucent screen plate 132 is approximately in the middle in two sections 136 and 138 divided. The first paragraph 136 is in front of the optical unit 130 attached and has a relatively high transmittance. The second section 138 is attached in front of the eye, where the optical unit 10 is not arranged, and has a relatively low transmittance. For the reason discussed in the second embodiment, the difference in transmittance between the first section is 136 and the second section 138 preferably set such that there is a difference between the total transmittance of the first section 136 and the half mirror 18 and the transmittance of the second section 138 not greater than about 30%. The partially translucent screen plate 132 can work in the same way as in 2 shown half mirror 18 have a notch for the nose in their middle.

In the 18 (a) shown optical unit 130 becomes by means of the mechanism similar to that which 2 was discussed, moved between the left position and the right position. To the positions of the first section 136 and the second section 138 To exchange, the user takes the entire unit of the partially translucent screen plate 132 out of the groove 134 and turn her over to put her back in the groove 134 use. These manipulations allow the section 136 , which has a relatively high transmittance, in front of the eye with the optical unit 130 is located while the section 138 with a relatively low transmittance in front of the other eye. This leads to a reduction the brightness difference between the light beams entering the left eye and the right eye.

The first paragraph 136 and the second section 138 the partially translucent screen plate 132 can be separated from each other. This separation allows the sections 136 and 138 independently of each other out of the groove 134 to take and back into the groove 134 to use after the positions have been exchanged. This structure does not require a single operation to the two sections 136 and 138 Turning around, however, increases the number of steps to attach and detach.

M. Ninth arrangement

19 Fig. 10 illustrates the structure of an optical system of another HMD as a ninth arrangement. An optical unit 140 has a structure similar to that of the optical unit 95 the in 15 is similar to the fifth arrangement shown, except that the half mirror 18 through a polarizing beam splitter 142 replaced is that the partially translucent screen plate 96 through a polarizing plate 146 is replaced, and that a λ / 4 plate 144 slightly above the concave half mirror 92 is arranged. The kon kave half mirror 92 could be replaced by a concave mirror.

The from the liquid crystal screen 2 emitted image beam L1 passes through the polarizing beam splitter 142 and enters the λ / 4 plate 144 one. The from the liquid crystal screen 2 emitted light beams L1 is p-polarized light, and the polarizing beam splitter 142 behaves so that it transmits p-polarized light to almost 100% and reflects s-polarized light to almost 100%. The image beam L1, which is the polarizing beam splitter 142 is crossed, by means of the λ / 4 plate 144 is transferred into circularly polarized light and is then from the inner surface of the concave half mirror 92 reflected. The reflection on the concave half mirror 92 reverses the direction of rotation of the vibration vector of the circularly polarized light. The image beam L1 of circularly polarized light re-enters the λ / 4 plate 144 and is converted into s-polarized light. The image beam L1 of s-polarized light is received by the polarizing beam splitter 142 reflects and enters the eye 10 of the user.

On the other hand, the background beam L2 contains randomly polarized light components, and only the p-polarized light component passes through the polarizing plate 146 , Almost 100% of the proportion of the background beam L2, which is the polarizing plate 146 further passes through the polarizing beam splitter 142 and enters the eye 10 of the user.

As discussed above, since the image combining means used in the ninth arrangement becomes the polarizing beam splitter 142 include the image beam L1 from the liquid crystal panel 2 Reflected here or passed without significant losses. This improves the brightness of the display image observed by the user. A replacement of the concave half mirror 92 a concave mirror further improves the brightness of the observed display image. One possible modification uses a partially translucent screen plate for only one eye or both eyes to adjust the brightness relationship between the background image and the display image.

H. Fifth embodiment

20 Fig. 11 shows the appearance of still another HMD as a fifth embodiment according to the present invention. This HMD contains a plate 150 with variable transmittance for two eyes. Any of the optical units discussed in the embodiments given above could be used herein as an optical unit to allow the image beam L1 to enter the user's eye.

21 is a block diagram showing the electrical structure of the plate 150 with variable transmittance and a control circuit 160 showing it. The plate 150 with variable transmittance has the structure of a liquid crystal screen, wherein they have two transparent electrodes 152 and 154 , each comprising at least the visual fields of the virtual images for the left eye and the right eye, and a translucent counter electrode 156 with a large area covering these translucent electrodes 152 and 154 encloses, contains. The translucent counterelectrode 156 is grounded, and the left and right translucent electrodes, 152 and 154 , are connected to the control circuit 160 connected.

The control circuit 160 contains two drive circuits for the transparent electrodes 152 and 154 , Each drive circuit includes a buffer amplifier 162 , an operational amplifier 164 , a variable resistor 166 and a resistance 168 , The operational amplifier 164 takes over the variable resistor 166 and the resistance 168 a partial voltage from a supply contrary. An output terminal of the operational amplifier 164 is connected to a supply connection of the isolation amplifier 162 connected. The supply voltage whose level is due to the variable resistor 166 and the operational amplifier 164 is determined, is accordingly the isolating amplifier 162 fed. The user can change the value of the variable resistor 166 arbitrarily set by operating a dialing option, not shown.

An input terminal of the isolation amplifier 162 receives a pulse signal Ps for driving the disc 150 with variable transmittance, which is constructed as a kind of liquid crystal screen. The isolation amplifier 162 modulates the amplitude of the pulse signal Ps in response to the supply voltage supplied by the operational amplifier 164 is supplied, and supplies the modulated pulse signal to the transparent electrode 152 (or 154 ).

The left and right transmittances of the plate 150 with variable transmittance is in each case with a change in the amplitude of the drive signal, the light-transmitting electrodes 152 and 154 is given, changed. The value of the variable resistor 166 can for the left translucent electrode 152 and for the right translucent electrode 154 be set independently, so that the left and the right light transmittance of the plate 150 with variable transmittance can be controlled independently. This structure makes it possible to control the brightness of the visual field in the eye that sees the display image or in the eye that does not see the display image, thereby easily adjusting the environment to facilitate observation of the images by the user ,

In the above embodiments can, as far as possible, the plane half-mirror or the concave half-mirror through a half-transparent mirror with polarization selectivity (For example, a polarizing beam splitter) are replaced. The half mirror could hence as a semipermeable mirror without polarization selectivity or as a semi-permeable one Mirror be realized with polarization selectivity.

The partially translucent Sieve plate in the corresponding embodiments could by means of a semipermeable Elements without polarization selectivity or by means of a semipermeable element with polarization selectivity be realized. These semipermeable elements are preferred thin plates, although also blocks permissible are. The term "plates" here has a broad Meaning, with both non-curved plate elements as well domed Plate elements are included.

Of the Reflex mirror in the respective embodiments can by a other optical element to be replaced, which is a reflective surface has (for example, a prism). In addition, an optical element, which has a polarization-separating surface, in general be used as a polarizing beam splitter.

For the image display means, a variety of devices may be used by the liquid crystal display 2 are different, find application. For example, another flat panel display, such as a plasma display panel, could be used instead.

The The present invention is not limited to the above embodiments or their modified examples, but it could be many further modifications, modifications and variations, without departing from the scope of the vorlie invention as by the attached claims defined to come off.

industry Elle applicability

The Head mounted display device of the present invention is displayed as a display device of computers or as instructions Device for support applicable from manual controls.

Claims (19)

A head-mounted display device adapted to be mounted on the head of a user, comprising: image display means; magnifying optical means ( 26 ) to break a first light beam representing an image formed on the image display means, thereby enlarging the image so as to obtain an enlarged virtual image to be observed by the user with one of his two eyes; Image combination means ( 18 ) to let the first light beam representing the virtual image enter the user's eye simultaneously with a second light beam from a background view, thereby combining the virtual image with the background view to produce a composite image; and switching means to control the magnifying optical means ( 26 ) and the image combining means ( 18 ) to shift between a first state in which the image composed of the virtual image and the background view is observed with an eye of the user and a second state in which the composite image is observed with the other eye of the user , wherein the magnifying optical means ( 26 ) and the image combining means ( 18 ) are arranged such that the first light beam emitted by the image display means is detected by the magnifying optical means (12). 26 ) and the image combinations medium ( 18 ) goes in that order before it reaches the user's eye; wherein the head mounted display device is characterized in that the image combining means are located approximately at the center of a span of the head mounted display device such that they are positioned approximately midway between the eyes of the user; they further comprise deflection means ( 50 ) to the first light beam emitted from the image display means to the magnifying optical means ( 26 ) to distract; and the switching means comprise shape conversion means for detecting the magnifying optical means ( 26 ) and the image combining means ( 18 ) to move to predetermined stationary positions corresponding to the first state and the second state, respectively, and the shape of the deflection means ( 50 ) by the movement so that a direction of the deflection by the deflection means ( 50 ) to the positions of the magnifying optical means ( 26 ) and the image combining means ( 18 ) fits. A head mounted display device according to claim 1, wherein the deflection means ( 50 ) substantially parallel two reflective surfaces ( 23 . 24 ); and the shape conversion means comprise means for varying an angle of the two reflecting surfaces ( 23 . 24 ) suitable for the first state and the second state, respectively. A head-mounted display device according to claim 1, wherein said deflection means comprises first and second reflective surfaces (Figs. 23 . 24 ) which are fixed and the first light beam to corresponding positions of the magnifying optical means ( 26 ) in the first state and in the second state, and a rotatable, third reflective surface (FIG. 31 ); and the shape conversion means comprise means for varying an angle of the third reflective surface ( 31 ) suitable for the first state and the second state, respectively. A head-mounted display device adapted to be mounted on the head of a user, comprising: image display means; magnifying optical means ( 26 ) to break a first light beam representing an image formed on the image display means and thereby to enlarge the image so as to obtain an enlarged virtual image to be observed by the user with one of his two eyes; Image combination means ( 18 ) to let the first light beam representing the virtual image enter the user's eye simultaneously with a second light beam from a background view, thereby combining the virtual image with the background view to produce a composite image; and switching means to control the magnifying optical means ( 26 ) and the image combining means ( 18 ) to shift between a first state in which the image composed of the virtual image and the background view is observed with an eye of the user and a second state in which the composite image is observed with the other eye of the user , wherein the magnifying optical means ( 26 ) and the image combining means ( 18 ) are arranged such that the first light beam emitted by the image display means is detected by the magnifying optical means (12). 26 ) and the image combining means ( 18 ) goes in that order before it reaches the user's eye; wherein the head mounted display device is characterized in that the image display means are located approximately in the center of a span of the head mounted display device such that they are positioned approximately midway between the eyes of the user; they also contain reflection means ( 80 ), which is a first ( 34 ) and a second ( 35 ) have reflective surfaces which are fixed and the first light beam emitted by the image display means is directed towards corresponding positions of the magnifying optical means (Figs. 26 ) in the first state and the second state, respectively; and the switching means comprise the radiation direction switching means for detecting the magnifying optical means (16). 26 ) and the image combining means ( 18 ) to move to corresponding preset stationary positions corresponding to the first state and the second state, respectively, and to change a radiation direction of the first light beam from the image display means by the movement so that the first light beam is emitted from either the first reflecting surface (12). 34 ) or of the second reflective surface ( 35 ) is reflected. Head mounted display device according to claim 4, wherein the radiation direction switching means, the image display means rotate. A head mounted display device according to any one of the preceding claims, further comprising a partially transmissive element ( 37 ) located in front of the eye that does not serve to observe the virtual image; and wherein the transmittance of the partially transmissive element ( 37 ) in a range of about 0.7 to 1.3 times the transmittance of the image combining means ( 18 ). The head mounted display device according to any one of claims 1 to 5, wherein the first light beam is polarized light; the image combining means comprise a polarizing beam splitter ( 39 ) that behaves so as to reflect a polarized light component of the first light beam; the head mounted display device further comprises a partially transparent element ( 40 ) disposed so as to extend beyond the polarizing beam splitter ( 39 ) is opposite the user; and the partially transmissive element ( 40 ) has a size that covers visual fields of a virtual image for both eyes of the user, and behaves as allowing only polarized light originating from a light beam from a background view to pass through the polarizing beam splitter (12). 39 ) can go. The head mounted display device according to any one of claims 1 to 5, wherein the display device further comprises a semi-transmissive element disposed in front of the eye which is not for viewing the virtual image; and wherein the switching means comprise means for transmitting the partially transparent element ( 110 ) in a direction conducive to the magnifying optical means ( 92 ) is opposite. A head mounted display device according to any one of claims 1 to 6 or claim 8, wherein said image combining means ( 18 . 142 ) and the magnifying optical means ( 92 . 98 ) are arranged so that the first light beam emitted by the image display means is passed through the image combining means at least once ( 18 . 142 ) and the magnifying optical means ( 92 . 98 ) passes in this order before it reaches the user's eye, the magnifying optical means ( 92 . 98 ) are designed so that they do not increase the background view. A head mounted display device according to claim 9, wherein said magnifying optical means ( 92 ) comprise a concave mirror; and the image combining means ( 18 . 142 ) and the magnifying optical means ( 92 ) are arranged so that the first light beam through the image combining means ( 18 . 142 ) after it has been reflected by the concave mirror and before it reaches the user's eye. The head mounted display device of claim 10, wherein the concave mirror is a concave half mirror; the image combining means ( 18 ) comprise a planar half mirror; and the concave half mirror is arranged to face the user beyond the plane half mirror. The head mounted display device of claim 10, wherein the concave mirror is a concave half mirror; the image combining means ( 18 . 142 ) comprise a planar half mirror; and the concave half mirror is arranged to face the image display means beyond the plane half mirror so that the first light beam, after being reflected by the concave half mirror, is reflected by the planar half mirror before reaching the user's eye. The head mounted display device of claim 10, wherein the image combining means ( 142 ) comprise a polarizing beam splitter which transmits at least a portion of the polarized light from the first light beam emitted from the image display means, and wherein the head mount display further comprises: a λ / 4 plate ( 144 ) interposed between the polarizing beam splitter and the concave mirror; and a partially transmissive element ( 146 ) which is arranged to face the user beyond the polarizing beam splitter, a partially transmissive element (Fig. 146 ) has a size covering the visual fields of a virtual image for both eyes of the user, and behaving as permitting polarized light to pass through the polarizing beam splitter. The head mounted display device of claim 9, wherein the head mounted display further comprises: a first partially transmissive element (10); 96 . 110 . 132 . 136 . 146 ) arranged to face the user beyond the image combining means. The head mounted display device of claim 14, further comprising: a second partially transmissive element (10); 138 ) located in front of the eye, which does not serve to observe the virtual image; wherein the first partially transparent element ( 136 ) has a higher transmittance than the second partially transmissive element ( 138 ) having. The head mounted display device of claim 15, wherein the relationships between the first (FIG. 136 ) and the second ( 138 ) and the eyes of the user can be reversed by the configuration of the attachment of the first ( 136 ) and the second ( 138 ) Element to the head-mounted display device is changed. A head mounted display device according to claim 9, wherein said image combining means ( 18 . 142 ) have a size covering the visual fields of the respective virtual images for both eyes of the user; and the switching means comprise means for relocating the magnifying optical means ( 92 . 98 ), thereby making a change between the first state and the second state such that a positional relationship between the image display means and the magnifying optical means (15) 92 . 98 ) is maintained substantially unchanged in the first state and in the second state. The head-mounted device of claim 9 or 10, wherein said image combining means ( 18 . 142 ) have a size covering a visual field of a virtual image for an eye of the user, but not covering a visual field of a virtual image for the other eye; and the switching means comprise means for relocating the magnifying optical means ( 92 . 98 ) and the image combining means ( 18 . 142 ) and thereby make a change between the first state and the second state in such a way that positional relationships between the image display means, the magnifying optical means ( 92 . 98 ) and the image combining means ( 18 . 142 ) are maintained substantially unchanged in the first state and in the second state. The head mounted display device of claim 9, further comprising: a partially transmissive element ( 110 . 138 ) located in front of the eye, which does not serve to observe the virtual image; wherein the partially transmissive element ( 110 . 138 ) has a transmittance substantially equal to the transmittance of the image combining means ( 18 . 142 ) is equal to.