JP7009273B2 - Ophthalmic device and its corneal shape measurement method - Google Patents

Description

The present invention relates to an ophthalmic apparatus for measuring the corneal shape of an eye to be inspected and a method for measuring the corneal shape thereof.

A keratometer and a corneal topographer device are well known as ophthalmic devices used for various examinations of the cornea of the eye to be inspected. The keratometer projects single to triple keratling light with a diameter of about 3φ (mm) onto the cornea of the inspected eye, and also photographs the anterior segment of the eye (cornea) to obtain the anterior eye of the inspected eye. The corneal curvature is measured based on the result of detecting the reflected image of the keratling light by image analysis of the part image. In addition, the corneal topographer device projects the platidling light onto the cornea and analyzes the image of the anterior segment obtained by photographing the anterior segment of the cornea to obtain a reflected image of the platidling light (platidling image). ) Is detected, and the corneal shape of the cornea [corneal curvature (curvature distribution), etc. of almost the entire area of the cornea] is measured.

In such an ophthalmic apparatus, various efforts have been made to accurately measure the corneal shape of the eye to be inspected.

For example, in the ophthalmic apparatus described in Patent Document 1, the image of the anterior segment obtained by photographing the anterior segment before projection of the platidling light is image-analyzed to relate to the shape and position of the pupil edge of the eye to be inspected. Boundary information is acquired in advance. Then, in this ophthalmic apparatus, when performing image analysis of the anterior ocular segment image, the detection result of the ring image overlapping the pupil edge image in the platidling image is corrected based on the previously acquired boundary information, and then the detection result is corrected. Calculate the shape of the cornea.

Further, in the ophthalmic apparatus described in Patent Document 2, the virtual position of each ring image of the plaid ring image in the anterior ocular segment image is obtained based on the cross-sectional shape of the cornea obtained by the optical tomography method, and each ring image is obtained. Based on the virtual position of, the acceptance or rejection of the measured position of each ring image obtained by image analysis of the anterior eye portion image is determined, or the measured position is corrected.

Japanese Unexamined Patent Publication No. 2000-342536 Japanese Unexamined Patent Publication No. 2011-167359

Since the platidling light used in the corneal topographer device has the effect of illuminating the entire anterior segment of the eye, the anterior segment image obtained by this corneal topographer device includes the pupil and iris in addition to the platidling image. , And images of the sclera, etc. are included. On the other hand, the pupil diameter, which is the diameter of the pupil of the eye to be inspected, varies in the range of about 2φ to 6φ (mm) depending on individual differences and the brightness of the surroundings. Therefore, the plated ring image includes a ring image located on the pupil image and a ring image located on the iris image.

FIG. 11 is a graph showing a change in the luminance of a part of the anterior segment image (pupil image and iris image) along an arbitrary radial direction. The reference numeral "V" in the figure indicates a change in brightness corresponding to each ring image of the plated ring image.

As shown by the reference numeral XIA in FIG. 11, since the platidling light is not reflected in the pupil, the ring image located on the pupil image is located on the dark background (pupil image). On the other hand, since the iris has a higher reflectance of plaid ring light than the pupil, the ring image located on the iris image is located on a brighter background (on the iris) than the pupil image.

Therefore, when analyzing the corneal shape of the eye to be inspected from the anterior eye image, the threshold values (slice level) of different brightness are different for the ring image located on the pupil image and the ring image located on the iris image. ) Is set, and the position P0 [peak position (also referred to as the center of gravity position)] of each ring image is detected for each of a plurality of meridian directions of the anterior ocular segment image. Then, the shape of each ring image is detected by performing elliptical approximation or the like with respect to the position detection result of each ring image in each meridian direction, and the corneal shape is calculated based on the shape detection result of each ring image.

As shown by the reference numeral XIB in FIG. 11, depending on the pupil diameter of the eye to be inspected, one of the ring images of the plated ring image becomes an image of the pupil edge (pupil edge image) showing the boundary between the pupil of the inspected eye and the iris. May overlap. Specifically, the entire circumference of the ring image may overlap the pupil edge image, or the ring image may partially overlap the pupil edge image due to the shape or eccentricity of the pupil edge.

In this case, it becomes difficult to distinguish between the ring image and the pupil edge image. Further, when a part of the ring image overlaps with the pupil image, the brightness of this part becomes high, so that the apparent position P1 of the ring image moves to the iris image side from the actual position P0. As a result, it becomes impossible to accurately measure the shape of the ring image (ring diameter, etc.).

Furthermore, when the entire circumference of the ring image overlaps the entire circumference of the pupil edge image, the apparent ring image becomes large, so that the corneal curvature obtained by image analysis of the anterior ocular segment image is calculated more loosely than it actually is. .. Furthermore, when the ring image partially overlaps the pupil edge image, the shape of the ring image is distorted, so that it may be determined as astigmatism or irregular cornea. Therefore, it is possible to calculate the corneal shape by ignoring the ring image that overlaps with the pupil edge image, but the data of the most important part for measuring the corneal shape from 3φ (mm) to 6φ (mm) cannot be obtained. , The reliability of the measured value of the corneal shape may decrease.

Therefore, as described in Patent Document 1, a method of correcting the detection result of the ring image overlapping the pupil edge image can be considered based on the boundary information between the pupil and the iris acquired in advance. However, in this method, when the position of the eye to be inspected or the pupil diameter changes between the imaging of the anterior segment at the time of acquiring boundary information and the imaging of the anterior segment at the time of measuring the corneal shape, the corneal shape is accurate. No measurement results can be obtained.

Further, as described in Patent Document 2, a method of calculating the corneal shape by using the virtual position of the ring image overlapping the pupil edge image instead of the actually measured position is also conceivable. However, even in this case, the reliability of the measured value of the corneal shape may decrease.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an ophthalmic apparatus capable of measuring the corneal shape of an eye to be inspected with high accuracy and a method for measuring the corneal shape thereof.

The ophthalmic apparatus for achieving the object of the present invention includes a pattern light projection optical system that projects pattern light for measuring the shape of the cornea onto the cornea of the eye to be inspected, and a cornea on which pattern light is projected from the pattern light projection optical system. The pupil diameter is changed by the corneal imaging image acquisition unit that acquires the corneal imaging image including the reflected image of the pattern light, the pupil diameter change portion that changes the pupil diameter of the subject eye at least once, and the pupil diameter change portion. Each time it was changed, it was acquired by the re-execution control unit and the corneal imaging image acquisition unit that re-execute the projection of the pattern light by the pattern light projection optical system and the acquisition of the corneal imaging image by the corneal imaging image acquisition unit. From all the corneal images, the detection results of the interference reflection image detection unit that detects the interference reflection image, which is the reflection image that overlaps the pupil edge image showing the boundary between the pupil and the iris of the subject, and the detection result of the interference reflection image detection unit. Based on this, the normal reflection image detection unit that detects the normal reflection image, which is a reflection image that does not overlap the pupil edge image, and the normal reflection image detection unit detect from at least one of the corneal images acquired by the corneal imaging image acquisition unit. It is provided with a corneal shape calculation unit that calculates the corneal shape of the eye to be inspected based on the normal reflection image.

According to this ophthalmic apparatus, it is possible to reduce the position detection error of the reflected image of the pattern light and measure the corneal shape accurately (high accuracy).

In the ophthalmic apparatus according to another aspect of the present invention, the interference reflection image detection unit detects the interference reflection image from the corneal imaging image each time the corneal imaging image is acquired by the corneal imaging image acquisition unit, and interferes with the reflection. When the interference reflection image is not detected by the image detection unit, the stop control unit is provided to stop the change in the pupil diameter by the pupil diameter change unit and the re-execution by the re-execution control unit. As a result, if the interference reflection image is not detected by the interference reflection image detection unit, the measurement can be completed in a short time.

In the ophthalmic apparatus according to another aspect of the present invention, the pattern light projection optical system simultaneously projects a plurality of pattern lights onto the cornea, and the corneal imaging image acquisition unit receives a plurality of reflected images corresponding to the plurality of pattern lights. The corneal imaging image including the corneal imaging image is acquired, and the interference reflection image detection unit includes the interference reflection image in the plurality of reflection images in the corneal imaging image from all the corneal imaging images acquired by the corneal imaging image acquisition unit. The normal reflection image detection unit detects whether or not the condition is present, and based on the detection result of the interference reflection image detection unit, all the normal reflection images corresponding to all the reflection images are acquired by the corneal imaging image acquisition unit. It is individually detected from the corneal photographed image, and the corneal shape calculation unit calculates the corneal shape of the eye to be inspected based on all the normal reflection images detected by the normal reflection image detection unit. Since all the positions and shapes of the reflected images of the plurality of pattern lights can be measured accurately (high accuracy), the corneal shape of the eye to be inspected can be measured with high accuracy.

In the ophthalmic apparatus according to another aspect of the present invention, the pattern light projection optical system projects pltedling light including a plurality of concentric ring lights as a plurality of pattern lights onto the eye to be inspected.

In the ophthalmic apparatus according to another aspect of the present invention, the pattern light projection optical system projects pattern light, which is invisible light, onto the eye to be inspected.

In the ophthalmic apparatus according to another aspect of the present invention, the pupil diameter changing portion is a visible light projection optical system that projects visible light onto the eye to be inspected, and the pupil is changed by changing the amount of visible light projected on the eye to be inspected. It is a visible light projection optical system that changes the diameter.

In the ophthalmic apparatus according to another aspect of the present invention, the measurement light projection optical system that projects the measurement light for measuring the eye characteristics onto the fundus of the eye to be inspected and the reflected light of the measurement light reflected by the fundus are received. A light receiving unit that acquires a reflected image and an eye characteristic calculation unit that calculates the eye characteristics of the eye to be inspected based on the reflected image acquired by the light receiving unit are provided, and the pupil diameter changing unit is reflected by the light receiving unit. The pupil diameter is changed after the image is acquired. This prevents the influence of changes in pupil diameter from affecting the measurement results of eye characteristics.

The corneal shape measuring method of the ophthalmic apparatus for achieving the object of the present invention is a pattern light projection step of projecting a pattern light for measuring the corneal shape onto the cornea of the eye to be inspected, and a pattern light projection step in which the pattern light is projected. In the corneal imaging image acquisition step of photographing the existing cornea and acquiring the corneal imaging image including the reflected image of the pattern light, the pupil diameter change step of changing the pupil diameter of the subject eye at least once, and the pupil diameter change step. Each time the pupil diameter is changed, the pattern light projection by the pattern light projection step and the acquisition of the corneal imaging image by the corneal imaging image acquisition step are re-executed in the re-execution control step and the corneal imaging image acquisition step. In the interference reflection image detection step and the interference reflection image detection step, which detect an interference reflection image that is a reflection image overlapping the pupil edge image showing the boundary between the pupil and the iris of the eye to be inspected, from all the corneal images taken. Based on the detection result, a normal reflection image detection step that detects a normal reflection image that is a reflection image that does not overlap the pupil edge image from at least one of the corneal images acquired in the corneal imaging image acquisition step, and a normal reflection image detection. It has a corneal shape calculation step for calculating the corneal shape of the eye to be inspected based on the normal reflection image detected in the step.

The present invention can measure the corneal shape of the eye to be inspected with high accuracy.

It is an optical layout diagram which showed the arrangement of the optical system of an ophthalmic apparatus. It is a front view of the plaid ring seen from the side to be examined. It is a front view of the light receiving surface of the area sensor of the 2nd light receiving optical system. It is a functional block diagram of the integrated control unit of an ophthalmic apparatus. It is explanatory drawing for demonstrating the detection of the interference ring image in the photographed image data by the interference ring image detection unit. It is explanatory drawing for demonstrating the detection of each normal ring image by the 1st detection method by a normal ring image detection part. Reference numeral 7A is an explanatory diagram showing an example of the first captured image data in FIG. 6, and reference numeral 7B is an explanatory diagram showing an example of the second captured image data in FIG. It is explanatory drawing for demonstrating the detection of each normal ring image by the 2nd detection method by a normal ring image detection part. Reference numeral 9A is an explanatory diagram showing an example of the first captured image data in FIG. 8, and reference numeral 9B is an explanatory diagram showing an example of the second captured image data in FIG. It is a flowchart which shows the flow of the measurement process of the eye characteristic and the corneal shape of the eye to be examined by the ophthalmic apparatus. It is a graph which showed the luminance change of a part of an anterior eye part image along an arbitrary radial direction.

[Configuration of ophthalmic appliances]
FIG. 1 is an optical layout diagram showing an arrangement of an optical system of the ophthalmic apparatus 10 of the present invention. Here, the X-axis direction in the figure is the left-right direction (the eye width direction of the subject E) with respect to the subject, the Y-axis direction is the vertical direction, and the Z-axis direction is before approaching the subject. It is a front-back direction (also called a working distance direction) parallel to the direction and the rear direction away from the subject.

As shown in FIG. 1, the ophthalmic apparatus 10 is a multifunction device that measures both the eye characteristics of the eye to be inspected E and the corneal shape of the cornea Ec in the anterior segment of the eye to be inspected E. In this embodiment, as the measurement of the eye characteristics of the eye to be inspected E, the measurement of the optical refractive power and the wavefront aberration of the eyeball of the eye to be inspected E will be described as an example. Further, the measurement of the corneal shape of the present embodiment includes the measurement of the corneal wave surface aberration obtained from the corneal shape in addition to the measurement of the corneal curvature and the radius of curvature of almost the entire region or a part of the corneal Ec. It shall be.

The ophthalmic apparatus 10 includes an eye characteristic measurement optical system 12, a corneal shape measurement optical system 14, an alignment optical system 16, and a fixation optical system 18.

[Optical system for measuring eye characteristics]
The eye characteristic measurement optical system 12 includes a measurement light projection optical system 20 and a first light receiving optical system 22 (corresponding to a light receiving unit of the present invention). The measurement light projection optical system 20 projects the measurement light L1 for measuring the eye characteristics onto the fundus Ef of the eye E to be inspected. The first light receiving optical system 22 receives the reflected light of the measurement light L1 reflected by the fundus Ef and outputs the eye characteristic measurement data D1 corresponding to the reflected image of the present invention.

<Measurement light projection optical system>
The measurement light projection optical system 20 includes a measurement light source 26, a collimeter lens 28, a polarization beam splitter 30, a dichroic mirror 32, a dichroic mirror 34, an objective lens 36, and a light source moving unit 38.

The measurement light source 26 emits, for example, the measurement light L1 in the near infrared wavelength region toward the collimator lens 28. As the measurement light source 26, for example, an SLD (Super luminescent diode), a laser light source, an LED (Light emitting diode), or the like is used. Further, the measurement light source 26 is movably held by the light source moving unit 38 along a direction parallel to the emission direction of the measurement light L1.

The collimator lens 28 converts the measurement light L1 incident from the measurement light source 26 into parallel light, and then emits the measurement light L1 to the polarization beam splitter 30.

The polarization beam splitter 30 reflects the P polarization component of the measurement light L1 incident from the collimator lens 28 toward the dichroic mirror 32. Further, the polarization beam splitter 30 transmits the S polarization component of the reflected light of the measurement light L1 incident from the fundus Ef incident from the dichroic mirror 32 and incidents it on the reflecting mirror 40 described later.

The dichroic mirror 32 reflects the measurement light L1 incident from the polarized beam splitter 30 toward the dichroic mirror 34, and reflects the reflected light of the measurement light L1 incident from the dichroic mirror 34 toward the polarized beam splitter 30. Further, the fixation target light L5 incident from the reflector 96 described later is transmitted and incident on the dichroic mirror 34.

The dichroic mirror 34 reflects the measurement light L1 and the fixation target light L5 incident from the dichroic mirror 32 toward the objective lens 36, and directs the reflected light of the measurement light L1 incident from the objective lens 36 toward the dichroic mirror 32. Reflects. Further, the dichroic mirror 34 transmits the reflected light of the later-described platidling light L2 incident from the objective lens 36 and emits the light toward the later-described half mirror 70, and the later-described XY alignment light incident from the half mirror 70. It passes through L4 and emits light toward the objective lens 36.

The objective lens 36 is commonly used in each optical system except the ring optical projection optical system 52 described later, and causes the measurement light L1, the XY alignment light L4, and the fixation target light L5 to be incident on the eye E to be inspected.

<First light receiving optical system>
The first light receiving optical system 22 shares the polarizing beam splitter 30, the dichroic mirrors 32, 34, and the objective lens 36 with the measurement optical projection optical system 20, and also shares the reflecting mirror 40, the lens 42, the collimator lens 43, and the Hartmann. It has a plate 44, an area sensor 46, and a sensor driving unit 48.

The reflecting mirror 40 reflects the reflected light of the measurement light L1 incident from the polarizing beam splitter 30 toward the lens 42. As a result, the reflected light of the measurement light L1 is converted into parallel light by the collimator lens 43 via the lens 42, and then incident on the Hartmann plate 44.

The Hartmann plate 44 has a plurality of microlenses arranged two-dimensionally, and the reflected light of the measurement light L1 incident from the lens 42 is divided into a plurality of divided lights and incident on the light receiving surface of the area sensor 46.

The area sensor 46 is, for example, a CMOS (complementary metal oxide semiconductor) type or CCD (Charge Coupled Device) type image pickup device. The area sensor 46 receives (impresses) a plurality of divided lights incident from the Hartmann plate 44, and obtains image data of a Hartmann image composed of a plurality of point images corresponding to each divided light to the fundus portion of the eye E to be inspected. The Ef eye characteristic measurement data D1 (corresponding to the reflected image of the present invention) is output to the integrated control unit 100 (see FIG. 4) described later.

The sensor drive unit 48 movably holds the collimator lens 43, the Hartmann plate 44, and the area sensor 46 along a direction parallel to the incident direction of the reflected light of the measurement light L1. The sensor driving unit 48 and the light source moving unit 38 described above are driven so that the measurement light source 26, the fundus Ef, and the area sensor 46 have a substantially conjugate positional relationship according to the refractive index of the eye E to be inspected.

[Corneal shape measurement optical system]
The corneal shape measuring optical system 14 includes a ring light projection optical system 52 and a second light receiving optical system 54. The ring light projection optical system 52 corresponds to the pattern light projection optical system of the present invention, and projects the placid ring light L2 onto the cornea Ec of the anterior eye portion of the eye E to be inspected. Further, the second light receiving optical system 54 corresponds to the corneal imaging image acquisition unit of the present invention, and photographs the corneal Ec (anterior eye portion) on which the platidling light L2 is projected, that is, the platidling light L2. The reflected light is imaged, and the photographed image data D2 of the anterior eye portion including the cornea Ec is output.

<Ring light projection optical system>
The ring light projection optical system 52 includes a platid ring 58, a pair of light sources 60, and a pair of collimator lenses 62.

FIG. 2 is a front view of the plaid ring 58 as seen from the side of the eye to be inspected E. As shown in FIG. 2 and FIG. 1 described above, the plaid ring 58 is formed in a substantially annular shape and has a central opening 66, a plurality of ring patterns 68, and a pair of openings 69.

The central opening 66 is a circular opening hole formed in the central portion of the platid ring 58, and the center thereof substantially coincides with the optical axis of the objective lens 36. Through this central opening 66, the measurement light L1, the XY alignment light L4, and the fixation target light L5 are incident on the eye E to be inspected, and the reflected light reflected by the eye E to be inspected is incident on the objective lens 36.

The plurality of ring patterns 68 are formed concentrically around the optical axis of the objective lens 36, and each of them transmits light. Further, on the back surface side (objective lens 36 side) of the platid ring 58, a plurality of LEDs and the like (not shown) are arranged along each ring pattern 68.

Each ring pattern 68 is illuminated by invisible light (eg, near-infrared light) emitted from each of the above-mentioned LEDs (not shown). As a result, as the pattern light for measuring the shape of the cornea of the present invention, the plaid ring light L2 composed of the transmitted light transmitted through each ring pattern 68 is projected onto the cornea Ec of the eye E to be inspected and reflected by the cornea Ec. The reflected light of the platidling light L2 is incident on the objective lens 36. The wavelength range of the platidling light L2, which is invisible light, is not particularly limited.

The pair of openings 69 are formed on the circumference of, for example, the third (or other than the third) ring pattern 68 from the inside to the outside of the platid ring 58.

The pair of light sources 60 are provided on the back surface side of the platid ring 58 corresponding to the pair of openings 69, respectively. The pair of light sources 60 emit Z-alignment light L3 toward the pair of collimator lenses 62, respectively.

The pair of collimator lenses 62 make the Z alignment light L3 incident from the pair of light sources 60 into parallel light, and then emit the Z alignment light L3 toward the pair of openings 69. As a result, the pair of Z-aligned lights L3 that have passed through the pair of openings 69 are projected onto the cornea Ec of the eye E to be inspected. Then, the reflected light of the pair of Z-aligned lights L3 reflected by the cornea Ec of the eye E to be inspected is incident on the objective lens 36 together with the reflected light of the pltedling light L2 described above.

[Second light receiving optical system]
Returning to FIG. 1, the second light receiving optical system 54 shares the dichroic mirror 34 and the objective lens 36 with the measurement optical projection optical system 20, and also includes a half mirror 70, a relay lens 72, an imaging lens 74, and an area. It has a sensor 76 and.

The half mirror 70 reflects the XY alignment light L4 incident from the reflecting mirror 84 described later toward the dichroic mirror 34. Further, the half mirror 70 transmits the reflected light of the placidling light L2, the pair of Z alignment light L3, and the XY alignment light L4 incident from the dichroic mirror 34 and incidents them on the relay lens 72. As a result, each reflected light is incident on the light receiving surface of the area sensor 76 via the relay lens 72 and the imaging lens 74.

[Alignment optical system]
The alignment optical system 16 shares the dichroic mirror 34, the objective lens 36, and the half mirror 70 with the second light receiving optical system 54, and has an alignment light source 80, a lens 82, and a reflecting mirror 84.

The alignment light source 80 emits the XY alignment light L4 toward the lens 82. After passing through the lens 82, the XY alignment light L4 is projected onto the corneal Ec of the eye E to be inspected as parallel light through the reflector 84, the half mirror 70, the dichroic mirror 34, and the objective lens 36. Then, the reflected light of the XY alignment light L4 reflected by the corneal Ec enters the light receiving surface of the area sensor 76 via the objective lens 36, the dichroic mirror 34, the half mirror 70, the relay lens 72, and the imaging lens 74. Will be done.

FIG. 3 is a front view of the light receiving surface of the area sensor 76 of the second light receiving optical system 54. As shown in FIG. 3, the area sensor 76 is a CCD type or CMOS type image sensor. On the light receiving surface of the area sensor 76, the plating lens 74 superimposes the image on the anterior segment of the eye, and the plating image 86, which is a reflection image based on the reflected light of the plating light L2, and the reflection of the pair of Z alignment light L3. A pair of bright spot images B1 that are reflected images based on light and a bright spot image B2 that is a reflected image based on the reflected light of the XY alignment light L4 are imaged.

The area sensor 76 captures an image of the anterior eye portion of the eye to be inspected E including a placid ring image 86, a pair of bright spot images B1, and a bright spot image B2, and captures image data D2 in a controlled control unit 100 (FIG. 4) Output to. The captured image data D2 corresponds to the captured corneal image of the present invention.

The plaid ring image 86 corresponds to a reflection image (by the cornea) of the pattern light of the present invention, and is a multiple ring image composed of a plurality of concentric ring images 87 (seven in the present embodiment). .. In the present embodiment, the plaid ring image 86 is composed of the seven-layered ring image 87, but the plaid ring image 86 may be composed of the double-layered or more ring image 87. Hereinafter, each ring image 87 is referred to as a first ring image 87, a second ring image 87, ... A seventh ring image 87 from the inside to the outside of the plated ring image 86.

Both the third ring image 87 (or another ring image 87) and the pair of bright spot images B1 show the alignment state of the ophthalmologic apparatus 10 with respect to the eye E to be inspected in the Z-axis direction. Further, the bright spot image B2 shows the alignment state of the ophthalmic apparatus 10 in the X-axis direction and the Y-axis direction with respect to the eye E to be inspected (see JP-A-2011-115387).

[Optometry optical system]
Returning to FIG. 1, the fixation optical system 18 corresponds to the pupil diameter changing portion and the visible light projection optical system of the present invention, and is due to the fixation or cloud fog of the subject E with respect to the subject E. Projects the optometry standard L5. The fixation optical system 18 shares the dichroic mirror 32, the dichroic mirror 34, and the objective lens 36 with the measurement optical projection optical system 20 described above, and also shares the light source 88, the lens 90, the fixation marker 92, and the lens 94. And a reflecting mirror 96, and an optotype moving unit 98.

The light source 88 emits illumination light in the wavelength range of visible light toward the lens 90. This illumination light is made parallel light by the lens 90 and then incident on the fixation target 92.

The fixation target 92 is, for example, a landscape or a radiation pattern, and is illuminated from behind by the illumination light incident from the lens 90. As a result, the fixation target light L5 is emitted from the fixation reference 92 toward the lens 94. The fixation target light L5 is incident on the eye E to be inspected through the lens 94, the reflector 96, the dichroic mirror 32, the dichroic mirror 34, and the objective lens 36, and is projected onto the fundus Ef thereof.

The optotype moving unit 98 integrally moves the light source 88, the lens 90, and the fixation target 92 according to the refractive power of the eye E to be inspected. As a result, the eye E to be inspected can be fixed. Further, the optotype moving unit 98 performs cloud fog to eliminate the influence of the adjustment of the eye E to be inspected when measuring the refractive power of the eye to be inspected E.

In the fixation optical system 18 of the present embodiment, the amount of illumination light emitted from the light source 88, that is, the fixation target light incident on the eye E to be inspected, is controlled by the control unit 100 (see FIG. 4) described later. The amount of light of L5 is changed. In the eye E to be inspected, the pupil diameter becomes smaller as the amount of visible light (fixed light L5) incident by the light reflex (pupillary light reflex) increases. By changing the amount of light, the pupil diameter of the eye E to be inspected can be changed.

[Structure of integrated control unit]
FIG. 4 is a functional block diagram of the integrated control unit 100 of the ophthalmic apparatus 10. As shown in FIG. 4, the integrated control unit 100 is an arithmetic circuit composed of various arithmetic units including, for example, a CPU (Central Processing Unit) or an FPGA (field-programmable gate array), a memory, and the like. In addition to the above-mentioned optical systems, an operation unit 102, a storage unit 104, a display unit 106, and an alignment drive unit 108 are connected to the integrated control unit 100. Then, the integrated control unit 100 comprehensively controls the operation of each unit of the ophthalmic apparatus 10 in response to the input operation to the operation unit 102 by the examiner.

The storage unit 104 stores the measurement results of the eye characteristics and the corneal shape of the eye E to be inspected, and also stores a measurement program (not shown) for executing the measurement by the ophthalmic apparatus 10. The display unit 106 displays the eye characteristics of the eye E to be inspected, the measurement result of the corneal shape, and the like. The alignment drive unit 108 moves each optical system of the ophthalmic apparatus 10 relative to the eye to be inspected E in each axial direction of the XYZ axes under the control of the integrated control unit 100, so that the ophthalmic apparatus is relative to the eye to be inspected E. 10 is auto-aligned.

By executing a measurement program (not shown) read from the storage unit 104, the integrated control unit 100 includes an eye characteristic measurement control unit 110, a first image acquisition unit 112, an eye characteristic calculation unit 114, and a corneal shape measurement control unit 116. It functions as a second image acquisition unit 118, an alignment detection unit 120, an interference ring image detection unit 122, a normal ring image detection unit 124, and a corneal shape calculation unit 126.

The eye characteristic measurement control unit 110 controls the measurement of the eye characteristic of the eye to be inspected E by the ophthalmic apparatus 10. The eye characteristic measurement control unit 110 controls the fixation optical system 18 to cause the eye E to be inspected to become a cloud fog (when measuring the eye refractive force), and the eye characteristic measurement optical system 12 (measurement light projection optical system 20 and the first eye characteristic measurement control unit 110). The light receiving optical system 22) is controlled to project the measurement light L1 onto the fundus Ef of the eye E to be inspected, to capture the reflected light of the measurement light L1, and to output the eye characteristic measurement data D1.

The measurement of the eye characteristics of the eye E to be inspected will be described in detail later, but it is the timing after the acquisition of the first captured image data D2 for the measurement of the corneal shape of the eye E to be inspected by the corneal shape measurement optical system 14. Moreover, when the pupil diameter of the eye E to be inspected is changed by the fixation optical system 18, it is executed at the timing before the change.

Further, the measurement of the eye characteristics of the eye E to be inspected is not essential and may be omitted if unnecessary. In this case, by inputting the operation of stopping the measurement of the eye characteristics to the operation unit 102, the measurement of the eye characteristics of the eye to be inspected E by the ophthalmic apparatus 10 is omitted.

The first image acquisition unit 112 constitutes the fundus image acquisition unit of the present invention together with the first light receiving optical system 22 described above. The first image acquisition unit 112 acquires the eye characteristic measurement data D1 of the fundus Ef output from the first light receiving optical system 22, and outputs the eye characteristic measurement data D1 to the eye characteristic calculation unit 114.

The eye characteristic calculation unit 114 analyzes the eye characteristic measurement data D1 input from the first image acquisition unit 112, and calculates eye characteristics such as the optical refractive power and eyeball wave surface aberration of the eye E to be inspected. Since the method for calculating the eye characteristics is a known technique (Japanese Patent Laid-Open No. 2011-115387), a specific description thereof will be omitted here. Then, the eye characteristic calculation unit 114 stores the calculation result of the eye characteristic of the eye to be inspected E in the storage unit 104 and displays it on the display unit 106.

The corneal shape measurement control unit 116 controls the measurement of the corneal shape of the cornea Ec of the eye E to be inspected by the ophthalmic apparatus 10. The corneal shape measurement control unit 116 first controls the fixation optical system 18 to fix the eye E to be inspected, and also controls the ring light projection optical system 52 and the alignment optical system 16 to control the eye E to be inspected. The optometry light L2, the pair of Z alignment optics L3, and the XY alignment optics L4 are projected onto the optometry Ec. Further, the corneal shape measurement control unit 116 controls the second light receiving optical system 54 to control the reflected light of each light, that is, the plated ring image 86, the pair of bright spot images B1 and the bright spot image shown in FIG. The image of the point image B2 and the output of the captured image data D2 for alignment detection are executed.

Further, the corneal shape measurement control unit 116 controls the corneal shape measurement optical system 14 after the alignment is completed, and the ring light projection optical system 52 projects the plated ring light L2 onto the corneal Ec and the second light receiving optical system 54. The first imaging (acquisition) of the platidling image 86 and the output of the first captured image data D2 are executed. After the output of the first captured image data D2, the eye characteristic measurement control unit 110 described above executes the measurement of the eye characteristic of the eye E to be inspected, if necessary.

Further, the corneal shape measurement control unit 116 will be described later after the measurement of the eye characteristics of the eye to be inspected E is completed, or after the output of the first captured image data D2 when the measurement of the eye characteristics of the eye to be inspected E is unnecessary. The detection result is acquired from the interference ring image detection unit 122. Next, the corneal shape measurement control unit 116 changes the pupil diameter of the eye E to be inspected by the fixation optical system 18 based on the detection result of the interference ring image detection unit 122, and the corneal shape in a state where the pupil diameter is changed. It is determined whether or not it is necessary to execute the acquisition of the second captured image data D2 by the measurement optical system 14.

Then, when the corneal shape measurement control unit 116 determines that the change in the pupil diameter and the acquisition of the second captured image data D2 are necessary, the corneal shape measurement control unit 116 controls the fixation optical system 18 and projects the fixation target onto the eye E to be inspected. By increasing the amount of light L5, the pupil diameter of the eye E to be inspected is changed (reduced). That is, the eye E to be inspected is miotic. Next, the corneal shape measurement control unit 116 controls the corneal shape measurement optical system 14 to project the platidling light L2 onto the cornea Ec, capture the second platidling image 86, and output the captured image data D2. Re-execute.

The second image acquisition unit 118 constitutes the corneal imaging image acquisition unit of the present invention together with the above-mentioned second light receiving optical system 54, and is an anterior eye unit (cornea Ec) output from the second light receiving optical system 54. Acquires the captured image data D2 of. When the second image acquisition unit 118 acquires the photographed image data D2 for alignment detection from the second light receiving optical system 54 before the alignment by the alignment drive unit 108 described above, the second image acquisition unit 118 transfers the photographed image data D2 to the alignment detection unit 120. Output. Further, when the second image acquisition unit 118 acquires the captured image data D2 from the second light receiving optical system 54 after the alignment by the alignment drive unit 108, the second image acquisition unit 118 outputs the captured image data D2 to the interference ring image detection unit 122.

The alignment detection unit 120 analyzes the captured image data D2 for alignment detection input from the second image acquisition unit 118, and as shown in FIG. 3 described above, the third ring image 87 and a pair of bright spots. Based on the positional relationship with the image B1, the alignment state of the ophthalmologic apparatus 10 with respect to the eye E to be inspected is detected in the Z-axis direction. Further, the alignment detection unit 120 detects the alignment state of the ophthalmic apparatus 10 with respect to the eye E to be inspected in the X-axis direction and the Y-axis direction based on the position of the bright spot image B2.

Then, the alignment detection unit 120 outputs the alignment detection result in each axis direction of the XYZ axes to the alignment drive unit 108. As a result, the alignment drive unit 108 executes the auto-alignment of the ophthalmic apparatus 10 with respect to the eye E to be inspected. Instead of executing the auto alignment, the alignment detection result by the alignment detection unit 120 may be displayed on the display unit 106, and the manual alignment may be performed to drive the alignment drive unit 108 in response to the input operation to the operation unit 102. good.

FIG. 5 is an explanatory diagram for explaining the detection of the interference ring image 87a in the captured image data D2 by the interference ring image detection unit 122. In order to clarify the pupil edge image Ed in the captured image data D2 showing the boundary between the pupil Ep of the eye to be inspected E and the iris Ei, the captured image data D2 shown by reference numeral 5A in FIG. The image data D2 (anterior segment image) in which the plaid ring image 86 is omitted is shown. Further, in the following description, it is assumed that the "pupil Ep" includes the pupil image in the photographed image data D2, and the "iris Ei" includes the iris image in the photographed image data D2.

As shown in FIG. 5 and FIG. 4 described above, the interference ring image detection unit 122 corresponds to the interference reflection image detection unit of the present invention, and analyzes the captured image data D2 in the captured image data D2. The interference ring image 87a is detected. The interference ring image 87a corresponds to the interference reflection image of the present invention, and is an image in which at least a part of each ring image 87 constituting the platid ring image 86 overlaps with the pupil edge image Ed.

In the captured image data D2, the luminance values of the pupil Ep, the iris Ei, and each ring image 87 are significantly different from each other. Therefore, the interference ring image detection unit 122 detects the luminance value for each pixel of the captured image data D2. Then, the interference ring image detection unit 122, based on the luminance value of each pixel of the captured image data D2, from within the captured image data D2, the pupil edge image Ed, the pupil Ep, which is the boundary between the pupil Ep and the iris Ei, and each ring. The boundary with the image 87 and the boundary between the iris Ei and each ring image 87 are detected.

At this time, for example, when the third ring image 87 completely overlaps with the pupil edge image Ed, the pupil edge image Ed cannot be detected by the interference ring image detection unit 122. In this case, the interference ring image detection unit 122 detects the third ring image 87 having a boundary with both the pupil Ep and the iris Ei as the interference ring image 87a.

Further, when any of the ring images 87 overlaps with a part of the pupil edge image Ed, only a part of the pupil edge image Ed is detected by the interference ring image detection unit 122. In this case, the interference ring image detection unit 122 detects the image intersecting the pupil edge image Ed in each ring image 87 as the interference ring image 87a.

Further, when there is no image overlapping the pupil edge image Ed in each ring image 87, that is, the interference ring image 87a, the interference ring image detection unit 122 detects the entire circumference of the pupil edge image Ed. In this case, the interference ring image detection unit 122 detects that there is no interference ring image 87a in each ring image 87.

In this way, the interference ring image detection unit 122 detects the interference ring image 87a from the captured image data D2 based on the detection result of the brightness value for each pixel of the captured image data D2. The interference ring image detection unit 122 detects the pupil Ep, the iris Ei, and each ring image 87 from the captured image data D2 by using, for example, a pattern matching method, and based on these detection results, the captured image data D2. The interference ring image 87a may be detected. That is, the method of detecting the interference ring image 87a by the interference ring image detection unit 122 is not limited to the above method.

Then, when the interference ring image detection unit 122 detects the interference ring image 87a from the above-mentioned first captured image data D2, the first detection result is the normal ring image detection unit 124 and the above-mentioned. It is output to the corneal shape measurement control unit 116, respectively.

When the interference ring image 87a is not detected from the first captured image data D2 by the interference ring image detection unit 122, the corneal shape measurement control unit 116 obtains the reduced pupil of the eye E to be inspected by the fixation optical system 18 and the corneal shape. The acquisition of the second captured image data D2 by the measurement optical system 14 is stopped. In this case, the corneal shape measurement control unit 116 functions as the discontinuation control unit of the present invention.

On the other hand, when the interference ring image 87a is detected from the first captured image data D2, the corneal shape measurement control unit 116 controls the fixation optical system 18 and projects the fixation target light L5 onto the eye E to be inspected. Increase the amount of light. As a result, the eye E to be inspected is miotic due to light reflex and the pupil diameter of the pupil Ep becomes smaller, so that the interference ring image 87a in the first captured image data D2 and the pupil edge image Ed overlap (interference). Is resolved.

Next, the corneal shape measurement control unit 116 functions as a re-execution control unit of the present invention, controls the corneal shape measurement optical system 14, to project the platidling light L2, and to capture and capture the platidling image 86. Re-execute with the output of D2. As a result, the acquisition of the second captured image data D2 by the second image acquisition unit 118 and the second detection of the interference ring image 87a by the interference ring image detection unit 122 are repeatedly executed. Then, the interference ring image detection unit 122 outputs the second detection result to the normal ring image detection unit 124.

The normal ring image detection unit 124 corresponds to the normal reflection image detection unit of the present invention. Based on the detection result of the interference ring image detection unit 122, the normal ring image detection unit 124 receives each ring image 87 (first) that does not overlap the pupil edge image Ed from at least one of the first and second captured image data D2. The ring images 87 to the 7th ring image 87) are detected as the 1st normal ring image 87b to the 7th normal ring image 87b, respectively (see FIG. 6 and the like).

When the interference ring image 87a is not detected from the first captured image data D2, that is, when the second captured image data D2 is not acquired, the normal ring image detection unit 124 receives the first captured image data. All of each ring image 87 from D2 is detected as each normal ring image 87b (first normal ring image 87b to seventh normal ring image 87b).

On the other hand, when the interference ring image 87a is detected from the first captured image data D2, that is, when the second captured image data D2 is acquired, the normal ring image detection unit 124 performs the first and second shots. Each normal ring image 87b is detected from at least one of the captured image data D2. Specifically, the normal ring image detection unit 124 detects each normal ring image 87b by using the following first detection method or second detection method based on the second detection result of the interference ring image detection unit 122. ..

FIG. 6 is an explanatory diagram for explaining the detection of each normal ring image 87b by the first detection method by the normal ring image detection unit 124. Reference numeral 7A in FIG. 7 is an explanatory diagram showing an example of the first captured image data D2 in FIG. 6, and reference numeral 7B is an explanatory diagram showing an example of the second captured image data D2 in FIG. Is.

As shown in FIGS. 6 and 7, when the interference ring image detection unit 124 does not detect the interference ring image 87a from the second captured image data D2, the normal ring image detection unit 124 uses the first detection method. Each normal ring image 87b is detected. Specifically, the normal ring image detection unit 124 detects all of the ring images 87 from the second captured image data D2 as the first normal ring image 87b to the seventh normal ring image 87b.

FIG. 8 is an explanatory diagram for explaining the detection of each normal ring image 87b by the second detection method by the normal ring image detection unit 124. Reference numeral 9A in FIG. 9 is an explanatory diagram showing an example of the first captured image data D2 in FIG. 8, and reference numeral 9B is an explanatory diagram showing an example of the second captured image data D2 in FIG. Is.

As shown in FIGS. 8 and 9, when the interference ring image detection unit 124 detects the interference ring image 87a from the second captured image data D2 by the interference ring image detection unit 122, the normal ring image detection unit 124 uses the second detection method. Each normal ring image 87b is detected. Specifically, the normal ring image detection unit 124 has the interference ring image 87a in the first captured image data D2 and the second captured image based on the first and second detection results by the interference ring image detection unit 122. The interference ring image 87a in the data D2 is discriminated from each other. Here, it is assumed that the third ring image 87 in the first captured image data D2 and the second ring image 87 in the second captured image data D2 are interference ring images 87a, respectively.

Then, the normal ring image detection unit 124 detects the second ring image 87 from the first captured image data D2 as the second normal ring image 87b, and detects the third ring image 87 from the second captured image data D2 to the third. It is detected as a normal ring image 87b. Further, the normal ring image detection unit 124 detects each of the remaining normal ring images 87b from the captured image data D2 of either the first time or the second time.

As described above, the normal ring image detection unit 124 does not overlap the pupil edge image Ed from at least one of the first and second captured image data D2 by either the first detection method or the second detection method. The ring image 87, that is, each normal ring image 87b can be detected. Then, the normal ring image detection unit 124 outputs the detection result of each normal ring image 87b to the corneal shape calculation unit 126.

The corneal shape calculation unit 126 is based on the detection result of each normal ring image 87b input from the normal ring image detection unit 124, and from each normal ring image 87b of at least one of the first and second captured image data D2, the cornea Calculate shape and corneal wavefront aberrations. Since the specific calculation method of the corneal shape and the corneal wavefront aberration is a known technique, a specific description thereof will be omitted here. Then, the corneal shape calculation unit 126 stores the calculation result of the corneal shape of the eye E to be inspected in the storage unit 104 and displays it on the display unit 106.

[Action of ophthalmic appliances]
FIG. 10 is a flowchart showing the flow of the measurement process of the eye characteristics and the corneal shape of the eye E to be inspected by the ophthalmic apparatus 10 having the above configuration (corresponding to the corneal shape measuring method of the ophthalmic apparatus of the present invention). First, the corneal shape measurement control unit 116 of the integrated control unit 100 controls the fixation optical system 18 to project the fixation target light L5 onto the fundus Ef of the eye E to be inspected with a normal amount of light. Make E stare (step S1).

Further, the corneal shape measurement control unit 116 controls the alignment optical system 16 and the ring light projection optical system 52, and the plaid ring light L2, the pair of Z alignment light L3, and the XY alignment light are applied to the anterior eye portion of the eye E to be inspected. Project L4. Further, the corneal shape measurement control unit 116 controls the second light receiving optical system 54 to capture an image of each reflected light (reflected image) from the eye E to be inspected and output the captured image data D2 for alignment detection. .. The captured image data D2 for alignment detection is input from the second light receiving optical system 54 to the alignment detection unit 120 via the second image acquisition unit 118.

The alignment detection unit 120 analyzes the captured image data D2 for alignment detection input from the second image acquisition unit 118, and analyzes the positional relationship between the third ring image 87 and the pair of bright spot images B1 and the bright spot image. Based on the position of B2, the alignment state of the ophthalmologic apparatus 10 with respect to the eye E to be inspected in the XYZ axis direction is detected. Then, the alignment detection unit 120 outputs the detection result of the alignment state to the alignment drive unit 108. As a result, the alignment drive unit 108 executes the auto-alignment of the ophthalmic apparatus 10 with respect to the eye E to be inspected (step S2). As described above, manual alignment may be performed instead of auto alignment.

When the above alignment is completed, the corneal shape measurement control unit 116 controls the corneal shape measurement optical system 14 to project the plated ring light L2 from the ring optical projection optical system 52 onto the corneal Ec (step S3), and the first step. 2 The first imaging (acquisition) of the platidling image 86 by the light receiving optical system 54 and the output of the first captured image data D2 (step S4) are executed. As a result, the first captured image data D2 is input from the second light receiving optical system 54 to the interference ring image detection unit 122 via the second image acquisition unit 118. Note that step S3 corresponds to the pattern light projection step of the present invention, and step S4 corresponds to the corneal imaging image acquisition step of the present invention.

When it is necessary to measure the eye characteristics of the eye to be inspected E after the acquisition of the first captured image data D2, the eye characteristic measurement control unit 110 starts the measurement of the eye characteristics of the eye to be inspected E (YES in step S5). .. In addition, since the eye to be inspected E is mioticized in step S11 and subsequent steps described later, by measuring the eye characteristics of the eye to be inspected E before that, it is possible to prevent the influence of the miosis on the measurement result of the eye characteristics. ..

The eye characteristic measurement control unit 110 controls the fixation optical system 18 described above to fog the eye E to be inspected, and also controls the eye characteristic measurement optical system 12 to control the eye characteristic E to be inspected by the measurement optical projection optical system 20. The projection of the measurement light L1 on the fundus Ef (step S6), the imaging of the reflected light of the measurement light L1 by the first light receiving optical system 22, and the output of the eye characteristic measurement data D1 (step S7) are executed. As a result, the eye characteristic measurement data D1 is input from the first light receiving optical system 22 to the eye characteristic calculation unit 114 via the first image acquisition unit 112. Then, the eye characteristic calculation unit 114 analyzes the eye characteristic measurement data D1 input from the first image acquisition unit 112, calculates the eye characteristics such as the optical refractive power and the eyeball wave surface aberration of the eye E to be inspected, and calculates the eye characteristics such as the eyeball wave surface aberration. The calculation result of the characteristic is stored in the storage unit 104 and displayed on the display unit 106 (step S8).

After the measurement of the eye characteristics of the eye to be inspected E is completed, or after the first acquisition of the captured image data D2 (NO in step S5) when the measurement of the eye characteristics of the eye to be inspected E is not performed, the interference ring image detection unit 122 As shown in FIG. 5 described above, the interference ring image 87a is detected from the first captured image data D2 (step S9). Note that step S9 corresponds to the interference reflection image detection step of the present invention. Then, the interference ring image detection unit 122 outputs the first detection result of the interference ring image 87a to the normal ring image detection unit 124 and the corneal shape measurement control unit 116, respectively.

When the interference ring image 87a is not detected from the first captured image data D2 by the interference ring image detection unit 122, the corneal shape measurement control unit 116 obtains the reduced pupil of the eye E to be inspected by the fixation optical system 18 and the corneal shape. The acquisition of the second captured image data D2 by the measurement optical system 14 is stopped (YES in step S10). In this case, the process proceeds to step S15 described later. As a result, if all of the normal ring images 87b can be detected from the first captured image data D2, the measurement can be completed in a short time by omitting the subsequent acquisition of new captured image data D2. Can be done.

On the other hand, when the interference ring image 87a is detected from the first captured image data D2 by the interference ring image detection unit 122, the corneal shape measurement control unit 116 condenses the pupil of the eye E to be inspected by the fixation optical system 18 and the corneal membrane. Acquisition of the second captured image data D2 by the shape measurement optical system 14 is started (NO in step S10, corresponding to the re-execution control step of the present invention).

First, the corneal shape measurement control unit 116 controls the fixation optical system 18 to project the fixation target light L5 onto the fundus Ef of the eye E to be inspected and increase the amount of the fixation reference light L5 (step S11, the pupil of the present invention). Corresponds to the diameter change step). As a result, the eye E to be inspected is fixed and the pupil is miotic due to the light reflex. As a result, the overlap between the interference ring image 87a in the at least the first captured image data D2 and the pupil edge image Ed is eliminated. In the present embodiment, by using the existing fixation optical system 18, the eye E to be inspected can be mioticized without changing the hardware of the ophthalmic apparatus 10.

Next, the corneal shape measurement control unit 116 controls the corneal shape measurement optical system 14 to project the plated ring light L2 onto the corneal Ec by the ring optical projection optical system 52 (step S12), and the second light receiving optical system 54. The second imaging of the platidling image 86 and the output of the second captured image data D2 (step S13) are executed. As a result, the cornea Ec (anterior segment) of the eye E to be inspected is photographed with different pupil diameters in the first and second times.

Then, the second captured image data D2 is input to the interference ring image detection unit 122, the second interference ring image 87a is detected by the interference ring image detection unit 122, and the detection result is output to the normal ring image detection unit 124. And are executed (step S14). Note that step S12 corresponds to the pattern light projection step of the present invention, step S13 corresponds to the corneal imaging image acquisition step of the present invention, and step S14 corresponds to the interference reflection image detection step of the present invention.

When the interference ring image 87a is not detected from the first captured image data D2, the normal ring image detection unit 124 detects all of the normal ring images 87b from the first captured image data D2.

On the other hand, when the interference ring image 87a is detected from the first captured image data D2, the normal ring image detection unit 124 shows the above-mentioned FIGS. 6 to 8 based on the detection result of the interference ring image detection unit 122. Each normal ring image 87b is individually detected from at least one of the first and second captured image data D2 by using the first detection method or the second detection method (step S15). Note that step S15 corresponds to the normal reflection image detection step of the present invention. Then, the normal ring image detection unit 124 outputs the detection result of each normal ring image 87b to the corneal shape calculation unit 126.

Upon receiving the input of the detection result of each normal ring image 87b, the corneal shape calculation unit 126 calculates the corneal shape and the corneal wave surface aberration based on at least one of the normal ring images 87b of the first and second captured image data D2. (Step S16, corresponding to the corneal shape calculation step of the present invention). The calculation result of the corneal shape and the like by the corneal shape calculation unit 126 is stored in the storage unit 104 and displayed on the display unit 106 (step S17).

[Effect of this embodiment]
As described above, in the ophthalmic apparatus 10 of the present embodiment, the photographed image data D2 of the same eye to be inspected E having different pupil diameters is acquired twice, and each ring image 87 (each normal ring image 87b) that does not overlap with the pupil edge image Ed is obtained. ) Is individually detected from the first and second captured image data D2, so that the position detection error of each ring image 87 of the plated ring image 86 can be reduced. In addition, the shape of the most important portion of the ring image 87 for measuring the shape of the cornea in the range of 3φ (mm) to 6φ (mm) can be accurately measured. As a result, the corneal shape of the eye E to be inspected can be measured with high accuracy.

[others]
In the above embodiment, the pattern light for measuring the corneal shape of the present invention has been described by taking as an example the 7-layer plaid ring light L2, but the single or double or more plaid ring light L2 (including the keratling light) has been described. , And the pattern light that can be used for measuring the corneal shape such as a predetermined pattern of dot light is not particularly limited. Further, one (one type) pattern light may be projected onto the eye E to be inspected, or a plurality of pattern lights such as the platidling light L2 may be projected onto the eye E to be inspected at the same time.

In the above embodiment, when the second captured image data D2 is acquired, the amount of light of the fixation target light L5 projected on the eye E to be inspected is increased to cause the eye E to be inspected to have miosis (decrease the pupil diameter). However, conversely, the amount of light of the fixation target light L5 projected on the eye E to be inspected may be reduced to cause the eye E to be inspected to have mydriasis (increase the pupil diameter).

In the above embodiment, the fixation optical system 18 has been described as an example of the pupil diameter changing portion and the visible light projection optical system of the present invention. For example, a visible light source is provided in the vicinity of the platid ring 58, and the visible light source is used. Visible light may be projected onto the eye E to be inspected, and the amount of visible light may be changed. Further, in this case, the visible light source may be provided separately from the ophthalmic apparatus 10.

In the above embodiment, the pupil diameter of the eye to be inspected E is changed by changing the amount of the fixation target light L5 (visible light) projected on the eye to be inspected E, but the eye on the opposite side of the eye to be inspected E is used. By changing the amount of visible light incident on the eye, the pupil diameter of the eye E to be inspected may be changed by utilizing indirect light reflex. Further, the pupil diameter may be changed by giving some kind of stimulus to the subject.

In the above embodiment, the pupil diameter of the eye E to be inspected is changed once by the fixation optical system 18, so that the projection of the platidling light L2 and the acquisition of the captured image data D2 by the corneal shape measurement optical system 14 are re-executed once. However, the number of changes in the pupil diameter and the number of re-executions described above are not limited to one. That is, even if the pupil diameter of the eye E to be inspected is changed a plurality of times by the fixation optical system 18, the projection of the platidling light L2 and the acquisition of the captured image data D2 by the corneal shape measurement optical system 14 are re-executed a plurality of times. good.

For example, when the normal ring image detection unit 124 detects each normal ring image 87b only by the first detection method shown in FIGS. 6 and 7, the interference ring image detection unit 122 detects the interference ring image 87a. The change in the pupil diameter of the eye E to be inspected by the fixation optical system 18 is repeated until is no longer detected. Further, every time the pupil diameter of the eye E to be inspected is changed by the fixation optical system 18, the projection of the placidling light L2 and the acquisition of the captured image data D2 by the corneal shape measurement optical system 14 are re-executed.

In the above embodiment, the interference ring image 87a is detected by the interference ring image detection unit 122 every time new captured image data D2 is acquired by the corneal shape measurement optical system 14. Not limited. For example, after the pupil diameter of the eye E to be inspected is changed a predetermined number of times (at least once) by the fixation optical system 18, and the captured image data D2 is acquired by the corneal shape measurement optical system 14 a predetermined number of times. Then, the interference ring image detection unit 122 may execute detection of the interference ring image 87a from all the captured image data D2.

In the above embodiment, between the acquisition of the first captured image data D2 by the corneal shape measurement optical system 14 and the acquisition of the second captured image data D2, the eye characteristics of the eye to be inspected E by the eye characteristic measurement optical system 12 are measured. Although the measurement is performed, the measurement of the eye characteristics of the eye to be inspected E may be performed before the acquisition of the first captured image data D2 by the corneal shape measurement optical system 14.

In the above embodiment, the case where the eye refractive force or the like is measured as the eye characteristic of the eye to be inspected E by the ophthalmic apparatus 10 has been described as an example, but various eye characteristics other than the eye refractive force [intraocular pressure, optics of the fundus of the eye] have been described. Tomographic images, corneal endothelial cells, axial length, etc.] may be measured.

In the above embodiment, a composite machine for measuring both the eye characteristics of the eye to be inspected E and the corneal shape of the cornea Ec has been described as an example of the ophthalmic apparatus 10, but the ophthalmic apparatus of the present invention includes the cornea of the cornea Ec. It also includes a corneal shape measuring device such as a corneal topographer device that measures the shape, and a keratometer that measures the corneal curvature of a part of the corneal Ec.

10 ... Ophthalmic equipment,
12 ... Ocular characteristic measurement optical system,
14 ... Corneal shape measurement optical system,
18 ... Optometry optical system,
20 ... Measurement light projection optical system,
22 ... First light receiving optical system,
52 ... Ring optical projection optical system,
54 ... Second light receiving optical system,
58 ... Platidling,
86 ... Platidling statue,
87 ... Ring statue,
87a ... Interference ring image,
87b ... Normal ring image,
100 ... Integrated control unit,
116 ... Corneal shape measurement control unit,
122 ... Interference ring image detector,
124 ... Normal ring image detector,
126 ... Corneal shape calculation unit

Claims (8)

A pattern light projection optical system that projects pattern light for measuring the shape of the cornea onto the cornea of the eye to be inspected,
A corneal imaging image acquisition unit that photographs the cornea on which the pattern light is projected from the pattern light projection optical system and acquires a corneal imaging image including a reflection image of the pattern light.
A pupil diameter changing portion that changes the pupil diameter of the eye to be inspected at least once,
Every time the pupil diameter is changed by the pupil diameter changing portion, the projection of the pattern light by the pattern light projection optical system and the acquisition of the corneal imaging image by the corneal imaging image acquisition unit are re-executed. Execution control unit and
An interference reflection image that detects an interference reflection image, which is a reflection image that overlaps the pupil edge image indicating the boundary between the pupil and the iris of the eye to be inspected, from all the corneal images acquired by the corneal imaging acquisition unit. With the detector
Based on the detection result of the interference reflection image detection unit, a normal reflection image which is a reflection image that does not overlap with the pupil edge image is detected from at least one of the corneal imaging images acquired by the corneal imaging image acquisition unit. Normal reflection image detector and
A corneal shape calculation unit that calculates the corneal shape of the eye to be inspected based on the normal reflection image detected by the normal reflection image detection unit, and a corneal shape calculation unit.
An ophthalmic device equipped with. The interference reflection image detection unit detects the interference reflection image from the corneal imaging image each time the corneal imaging image is acquired by the corneal imaging image acquisition unit.
It is provided with a stop control unit for stopping the change in the pupil diameter by the pupil diameter change unit and the re-execution by the re-execution control unit when the interference reflection image is not detected by the interference reflection image detection unit. The ophthalmic apparatus according to claim 1. The pattern light projection optical system simultaneously projects a plurality of the pattern lights onto the cornea.
The corneal imaging image acquisition unit acquires the corneal imaging image including the plurality of reflection images corresponding to the plurality of pattern lights.
Whether or not the interference reflection image is included in the plurality of reflection images in the corneal imaging image from all the corneal imaging images acquired by the interference reflection image detection unit. Detects
Based on the detection result of the interference reflection image detection unit, the normal reflection image detection unit obtains the normal reflection image corresponding to all the reflection images, and all the corneal imaging acquired by the corneal imaging image acquisition unit. Detected individually from the image,
The ophthalmic apparatus according to claim 1 or 2, wherein the corneal shape calculation unit calculates the corneal shape of the eye to be inspected based on all the normal reflection images detected by the normal reflection image detection unit. The ophthalmologic apparatus according to claim 3, wherein the pattern light projection optical system projects plaid ring light including a plurality of concentric ring lights as the plurality of pattern lights onto the eye to be inspected. The ophthalmic apparatus according to any one of claims 1 to 4, wherein the pattern light projection optical system projects the pattern light, which is invisible light, onto the eye to be inspected. The pupil diameter changing portion is a visible light projection optical system that projects visible light onto the eye to be inspected, and visible light projection that changes the pupil diameter by changing the amount of visible light projected on the eye to be inspected. The ophthalmic apparatus according to any one of claims 1 to 5, which is an optical system. A measurement light projection optical system that projects measurement light for measuring eye characteristics onto the fundus of the eye to be inspected.
A light receiving unit that receives the reflected light of the measured light reflected by the fundus and acquires a reflected image, and a light receiving unit.
An eye characteristic calculation unit that calculates the eye characteristics of the eye to be inspected based on the reflection image acquired by the light receiving unit, and an eye characteristic calculation unit.
Equipped with
The ophthalmic apparatus according to any one of claims 1 to 6, wherein the pupil diameter changing portion changes the pupil diameter after acquiring the reflected image by the light receiving portion. A pattern light projection step that projects a pattern light for measuring the shape of the cornea onto the cornea of the eye to be inspected,
A corneal imaging image acquisition step of photographing the cornea on which the pattern light is projected in the pattern light projection step and acquiring a corneal imaging image including a reflection image of the pattern light, and a corneal imaging image acquisition step.
The pupil diameter change step of changing the pupil diameter of the eye to be inspected at least once, and
Every time the pupil diameter is changed in the pupil diameter change step, the projection of the pattern light by the pattern light projection step and the acquisition of the corneal imaging image by the corneal imaging image acquisition step are re-executed. Control steps and
An interference reflection image that detects an interference reflection image, which is a reflection image that overlaps the pupil edge image indicating the boundary between the pupil of the eye to be inspected and the iris, from all the corneal images acquired in the corneal imaging acquisition step. Detection step and
Based on the detection result in the interference reflection image detection step, a normal reflection image which is a reflection image that does not overlap with the pupil edge image is detected from at least one of the corneal imaging images acquired in the corneal imaging image acquisition step. Normal reflection image detection step and
A corneal shape calculation step for calculating the corneal shape of the eye to be inspected based on the normal reflection image detected in the normal reflection image detection step, and a corneal shape calculation step.
A method for measuring the shape of a cornea of an ophthalmic appliance.

Images