JP5397912B2 - Reflective recursive front screen and reflective stereoscopic display screen - Google Patents

Description

  The present invention relates to a reflective recursive front screen and a reflective stereoscopic display screen.

Conventionally, there is a screen made of a diffusion film that diffuses incident light from within a specific angle region into the specific angle region.
For example, Patent Document 1 discloses a projection display screen that has a structure in which a plurality of diffusion films are laminated, the diffusion angle regions of the laminated films overlap, and the diffused light intensity distribution characteristics with respect to projector light are uniform. .
Further, Patent Document 2 discloses a projection display screen that includes a diffusion film that allows arbitrary control of the diffused light intensity distribution characteristics and whose diffusion angle region does not change with respect to incident light from a specific angle region. ing.

JP 2007-171523 A JP 2006-84563 A

The screens disclosed in Patent Documents 1 and 2 are capable of displaying high-quality images with little change in brightness depending on the observation angle.
Even if a large number of people project different images on the same screen using a personal projector from the direction they are looking at, such a screen crosstalks with the image projected by another person. There is also a need for a high-quality screen that only you can see.
In addition, a 3D screen that allows the right eye to see the right eye image and the left eye to see the left eye image is also desired by applying the fact that the visible image is switched sharply depending on the viewing angle of the screen.

  The present invention has been made in view of the above-described circumstances, and even if a large number of people project different images on the same screen using a personal projector from each viewing direction, the image projected by the other person To provide a reflective recursive front screen that can be seen only by itself without cross-talking with the projected image, and a reflective stereoscopic display screen using the reflective recursive front screen. With the goal.

  In order to achieve the above object, a reflective recursive front screen according to the present invention has a top-hat-like diffusion characteristic independent of an incident angle within a predetermined incident angle region and is transparent without diffusing outside the incident angle region. Among the screens made of a single internal refractive index distribution structure diffusing film having a characteristic and a screen in which a plurality of the same internal refractive index distribution structure diffusion films are laminated, one of the screens does not overlap the incident angle region. A plurality of laminated screen laminates, and a reflective film having retroreflective properties, on which the laminate is closely laminated.

  In the present invention, the screen stack is formed by stacking a plurality of screens so that their incident angle regions do not overlap. As a result, when an observer projects an image from a direction on the reflective recursive front screen with a personal projector or the like, only the internal refractive index distribution structure diffusion film constituting one screen among the plurality of stacked screens is obtained. Since the incident angle range matches the direction in which the image is projected, the light is diffused. The other internal refractive index distribution structure diffusion film exhibits the characteristic that light incident from this direction passes straight like glass, so that the incident light does not diffuse and the internal refractive index distribution structure diffusion film exists. The optical characteristics are the same as those in the case of not doing so.

The exit diffusion of this internal refractive index distribution structure diffusion film is a uniform diffusion characteristic limited within a predetermined angle region, and the exit diffused light is reflected in the direction of incidence by the retroreflective mirror. The angle region and the emission angle region substantially coincide with each other and are diffused and returned uniformly in the predetermined angle region in the direction of the observer.
Therefore, only an observer who is projecting with a personal projector can see a high-quality image with a uniform luminance distribution. As a result, even when a plurality of viewers project images on the same reflective recursive front screen from different directions, only the projected images can be viewed without crosstalk with images projected by other viewers. it can.

Further, in the reflective reflex front screen according to the present invention, the internal refractive index distribution structure diffusion film includes an incident direction of incident light incident on the predetermined incident angle region and the internal refractive index distribution structure diffusion film. Diffusion occurs only in a plane including two straight lines in the diffusion direction, and has a property of being transparent without being diffused outside the predetermined incident angle region, and the screen laminate includes diffusion of adjacent screens The directions are preferably substantially orthogonal to each other.
In this way, the screen laminate can control, for example, the vertical diffusion angle range and the horizontal diffusion angle range independently by laminating the screens whose diffusion directions are substantially orthogonal to each other.

Moreover, in the reflection type recursive front screen according to the present invention, the reflection film may be a triple mirror screen or a cat's eye lens reflection screen.
Thus, since the reflective film is a triple mirror screen (corner cube array) or a cat's eye lens reflective screen, both have two-dimensional recurrence, so that the vertical and horizontal directions are limited. A plurality of diffusion angle regions can be created.
Thus, it can be used by a large number of people not only in the horizontal direction but also in the vertical direction, and only the image projected by each person can be seen.
In the case of stereoscopic display, moving body parallax in the vertical direction as well as in the horizontal direction can be realized by making the screen a dome shape.

Moreover, in the reflection type recursive front screen according to the present invention, the reflection film may be a two-surface orthogonal matching mirror film having a reflection reflex characteristic limited to one direction or a one-dimensional cat-eye lens reflection screen.
As described above, when the reflective film is a two-surface orthogonal alignment mirror film or a one-dimensional cat's eye lens reflective screen whose reflection recursive characteristics are limited to one direction, the recursion only in the horizontal direction is sufficient. Since the mirror structure can be made much simpler than a triple mirror screen or a cat's eye lens reflecting screen, it can be easily manufactured and can be made inexpensive.
Furthermore, the structure of the screen laminate is also easy to manufacture because it is only necessary to realize a diffusion angle range limited only in the lateral direction, thereby reducing the number of internal refractive index distribution structure diffusion films to be laminated. Can be made inexpensive.

  Further, in the reflective stereoscopic display screen according to the present invention, any one of the reflective retrofront screens described above is formed in a curved state, projects different images from two different directions, and is reflected by the reflective film. The right eye of the observer is positioned on one side of the boundary between different images, and the left eye of the observer is positioned on the other side.

  In the present invention, the reflection type recursive front screen has a curved surface on which the image is projected, so that the position where all the boundaries of the different images coincide with each other appears. A high-quality stereoscopic image can be seen by installing the observer's right eye on one side of the boundary and the observer's left eye on the other side.

  According to the present invention, even when a plurality of viewers project images on the same reflective recursive front screen from different directions, only the projected images do not cross-talk with images projected by other viewers. Can see.

It is a figure which shows an example of the reflection type recursive front screen by embodiment of this invention.

Hereinafter, a reflective recursive front screen according to an embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 1, the reflective recursive front screen 1 according to the present embodiment includes a screen laminate 3 in which a plurality of screens made of a single internal refractive index distribution structure diffusion film 2 are laminated, a screen laminate 3, A reflective film 4 that is closely laminated.
In this embodiment, since the internal refractive index distribution structure diffusion film 2 and the screen are the same, the screen is also referred to as the internal refractive index distribution structure diffusion film 2 below.

The internal refractive index distribution structure diffusing film 2 is formed in an internal refractive index distribution structure, and uniformly diffuses incident light from within a predetermined angle region independently of the incident angle only within the predetermined angle region. Incident light incident from outside the angle range is transmitted through like a glass without being diffused at all.
Here, the predetermined angle region will be described as a diffusion angle region A below.
The plurality of internal refractive index distribution structure diffusion films 2 constituting the screen laminate 3 are laminated so that their diffusion angle regions do not overlap. The screen laminate 3 has a plurality of internal refractive index distribution structure diffusion films 2 that are overlapped with each other so that the diffusion angle areas do not overlap with each other. Can be diffused in the diffusion angle region.

For example, when the screen laminate 3 has a structure in which four internal refractive index distribution structure diffusion films 2a to 2d are laminated, the lateral diffusion angle region Aa of the first internal refractive index distribution structure diffusion film 2a is -15 ° to. 15 °, the lateral diffusion angle region Ab of the second internal refractive index distribution structure diffusion film 2b is 30 ° to 80 °, and the lateral diffusion angle region Ac of the third internal refractive index distribution structure diffusion film 2c is −80 ° to −30 °. The vertical diffusion angle region Ad of the fourth internal refractive index distribution structure diffusion film 2d is set to -15 ° to 15 °.
In addition, the lateral diffusion angle region and the longitudinal diffusion angle region of the internal refractive index distribution structure diffusion film 2 may be regions other than the numerical values described above, and the number of the internal refractive index distribution structure diffusion film 2 to be laminated is also a number other than four. It is good.

As the reflection film 4, a two-surface orthogonal alignment mirror film (for example, apex angle 90 ° reflection type, metal film coating, prism sheet) in which the function of the retroreflection mirror is limited to one direction is used.
The screen laminate 3 and the reflective film 4 are in close contact with the transparent optical adhesive 5.

  When one observer projects an image from one direction on the reflective recursive front screen 1 with a personal projector, among the laminated internal refractive index distribution structure diffusion films 2a to 2d, for example, the first internal refractive index. Only the distributed structure diffusion film 2a diffuses the light from this one direction within the incident angle range. The other second to fourth internal refractive index distribution structure diffusing films 2b, 2c, and 2d all exhibit the characteristics of allowing the incident light incident from one direction to pass straight like glass, so that the light is diffused. Therefore, the optical characteristics are the same as when they do not exist.

  The outgoing diffusion of the first internal refractive index distribution structure diffusion film 2a has a uniform diffusion characteristic limited within a limited angle, and the direction in which the outgoing diffused light is incident by the recursive mirror of the reflective film 4 The incident angle region and the exit angle region substantially coincide with each other by being reflected by the light. For this reason, the emitted diffused light is uniformly diffused and returned within the limited angular range toward the one observer who projected the image. Therefore, only one observer can see a high-quality image with a uniform luminance distribution.

  Note that when another observer projects an image from another direction different from the one observer, only the other internal refractive index distribution structure diffusion film 2 (for example, the second internal refractive index distribution structure diffusion film 2b) is in the other direction. From the incident angle range. The outgoing diffused light returns to the direction of another observer by the retroreflective mirror of the reflective film 4.

Next, the effect of the above-described reflective recursive front screen will be described with reference to the drawings.
According to the reflective recursive front screen according to the present embodiment, a large number of people can project different images by using a personal projector from the direction they are viewing, even if they project different images. The image has the effect of being visible only to you with high quality without crosstalk with the image projected by others.

Next, a reflective stereoscopic display screen to which the above-described reflective stereoscopic display screen is applied will be described.
The reflective stereoscopic display screen according to the present embodiment utilizes the fact that the boundaries of a plurality of limited diffusion angle regions possessed by the reflective recursive front screen 1 shown in FIG. 1 are steep, By curving the reflective recursive front screen 1 into a curved surface, a binocular or multi-lens reflective stereoscopic display screen without glasses is realized.
The reflection type recursive front screen 1 has a plane on which an image is projected, so that when an observer crosses the screen, the boundary between different images appears to move from the edge of the screen. Since the 3D display screen is formed with a curved surface on which an image is projected, a position where all the boundaries of different images coincide with each other appears. If a viewer's right eye is installed on one side of this boundary and the viewer's left eye is installed on the other side, a high-quality stereoscopic image can be seen.
By creating a plurality of such boundaries, expansion to the multi-view type is also conceivable.
The reflective stereoscopic display screen according to the present embodiment described above can easily project a stereoscopic image without 3D glasses.

  As described above, the embodiments of the reflective recursive front screen and the reflective stereoscopic display screen according to the present invention have been described. However, the present invention is not limited to the above-described embodiments, and may be changed as appropriate without departing from the scope of the present invention. Is possible.

For example, in the embodiment described above, the screen laminate 3 is formed by laminating a plurality of screens made of one sheet of the internal refractive index distribution structure diffusion film 2, but a plurality of the same internal refractive index distribution structure diffusion films are formed. A plurality of screens in which 2 are stacked may be stacked.
In the above-described embodiment, the diffusion characteristic is two-dimensional or one-dimensional. However, for example, when it is desired to control the vertical direction, the diffusion angle range, and the horizontal diffusion range independently, it is described in claim 1. Independent control can be easily realized by laminating a diffusion film whose diffusion characteristics are only one-dimensional in one direction so that the diffusion directions are orthogonal to each other.

  In the above-described embodiment, the reflective film 4 uses a two-surface orthogonal alignment mirror film in which the function of the retroreflective mirror is limited to one direction, but a triple mirror instead of the two-surface orthogonal alignment mirror film. A screen (corner cube array) or a cat's eye lens reflecting screen may be used. Since both of these have two-dimensional recursiveness, a plurality of limited diffusion angle regions in the vertical and horizontal directions can be created.

In the above-described embodiment, the reflective film 4 uses a two-surface orthogonal alignment mirror film in which the function of the retroreflective mirror is limited to one direction. A cat-eye lens reflecting screen (a film in which an element in which a cylindrical reflecting mirror is arranged in the focal plane of a cylindrical lens is arranged in an array like a lenticular lens) may be used.
In this way, when the recursion only in the horizontal direction is sufficient, the mirror configuration can be made much simpler than a triple mirror screen or a cat's eye lens reflection screen, and thus can be easily manufactured. At the same time, it can be made inexpensive.
Furthermore, the configuration of the screen laminate 3 is also only required to realize a diffusion angle range limited only in the lateral direction, so that the number of laminated internal refractive index distribution structure diffusion films 2 can be reduced. It can be manufactured and can be made inexpensive.

  In addition, since the two-surface orthogonal matching mirror film can reflect all the incident light only in the case of front incidence in the incident direction, some light is reflected by two reflection surfaces when incident from other than the front. Only one of them may hit, and the reflection efficiency may be reduced, and stray light may be generated, causing crosstalk. On the other hand, if the reflective film 4 is a one-dimensional cat-eye lens reflective screen, the opening of the cylindrical lens covers the entire screen, and when incident on the lens NA, all light is reflected in the incident direction. can do.

DESCRIPTION OF SYMBOLS 1 Reflective type front screen 2 Internal refractive index distribution structure diffusion film 3 Screen laminated body 4 Reflective film

Claims (5)

A screen comprising a single internal refractive index distribution structure diffusion film having a top hat-like diffusion characteristic independent of an incident angle within a predetermined incident angle region and having a characteristic of being transparent without being diffused outside the incident angle region; And a screen laminate in which one of the screens in which the same internal refractive index distribution structure diffusion film is laminated is laminated so that the incident angle regions do not overlap each other, and
A reflective recursive front screen comprising a reflective film having retroreflective properties and the laminate being closely laminated. The internal refractive index distribution structure diffusion film diffuses only in a plane including two straight lines of the incident light incident direction within the predetermined incident angle region and the diffusion direction of the internal refractive index distribution structure diffusion film. And has a characteristic of being transparent without diffusing outside the predetermined incident angle region,
The reflective recursive front screen according to claim 1, wherein the screen laminate has diffusion directions of adjacent screens substantially orthogonal to each other.   The reflective recursive front screen according to claim 1, wherein the reflective film is a triple mirror screen or a cat's eye lens reflective screen.   4. The reflection film according to claim 1, wherein the reflection film is a two-plane orthogonal alignment mirror film having a reflective reflex characteristic limited to one direction or a one-dimensional cat-eye lens reflection screen. 5. Reflective recursive front screen as described. The reflective recursive front screen according to any one of claims 1 to 4 , wherein the reflective recursive front screen is formed in a curved state, projects different images from two different directions, and reflects a boundary between the different images reflected by the reflective film. A reflective stereoscopic display screen, wherein the viewer's right eye is positioned on one side and the left eye of the viewer is positioned on the other side.

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