JP2006068110A - Ophthalmic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ophthalmic apparatus which examines a plurality of items subjected to an examination and uses an appropriate imaging optical system for every item subjected to the examination. <P>SOLUTION: The ophthalmic apparatus has a first light source 20, a first optical system 60 emitting first light from the first light source 20 obliquely to an eye E to be examined, a second optical system 64 which is disposed in a relation of specular reflection with the first optical system 60 and is a system where the first light reflected by the eye E passes, and a first image pickup device 46 receiving the first light passing through the second optical system 64. Moreover, the ophthalmic apparatus has a second light source 38 disposed on the side of the second optical system 64 and a second image pickup device 12 disposed on the side of the first optical system 60. Second light from the second light source 38 passes through at least a part of the second optical system 64 and enters the eye E from the same direction as the optical axis of the second optical system. The second light reflected by the eye E passes through at least a part of the first optical system 60 and is received by the second image pickup device 12. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ophthalmologic apparatus for examining the state of the cornea of a subject's eye (for example, corneal thickness, corneal endothelial cells, etc.).

As an apparatus for inspecting the state of the cornea of an eye to be examined, an apparatus disclosed in Patent Document 1 is known. The apparatus disclosed in Patent Document 1 includes an illumination optical system that irradiates illumination light from a light source obliquely toward the cornea of an eye to be examined. An imaging optical system for guiding the reflected light reflected by the eye to be examined to the imaging element is disposed at a position having a specular reflection relationship with the illumination optical system. The cornea image of the eye to be examined by the illumination optical system is received (photographed) by the imaging element via the imaging optical system.
JP-A-6-327634

  By the way, in this kind of ophthalmologic apparatus, if the item to be examined is different, the characteristics required for the photographing optical system are also different accordingly. For example, when examining (imaging) the state of corneal endothelial cells, since the corneal endothelium is a thin layer made of fine cells of about 20 microns, the imaging optical system is required to have high resolution (high resolution). . On the other hand, when examining (measuring) the corneal thickness, it is necessary to image a wide area from the corneal surface (corneal epithelium) to the corneal endothelium, so the high resolution required to inspect corneal endothelial cells is Not required. However, in the conventional ophthalmologic apparatus, even if it is possible to inspect a plurality of inspection target items, if an imaging optical system is configured in accordance with one inspection target item, an appropriate imaging optical system for other inspection target items There was a problem of not becoming.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to perform inspection using an appropriate imaging optical system for each inspection target item in an ophthalmologic apparatus capable of inspecting a plurality of inspection target items. It is to provide an ophthalmic device that can be used.

The ophthalmologic apparatus according to the present application includes a first light source and a first optical system that irradiates the first light from the first light source obliquely toward the eye to be examined. The first optical system is arranged in a substantially specular reflection relationship, and the second optical system through which the first light reflected by the eye to be examined passes, and the first light that receives the first light that has passed through the second optical system. A photographing element is provided. Therefore, the image of the eye to be inspected by the light emitted from the first light source to the eye to be examined is observed (photographed) by the first imaging element via the second optical system.
Furthermore, the ophthalmologic apparatus of the present application includes a second light source disposed on the second optical system side and a second imaging element disposed on the first optical system side. The second light from the second light source passes through at least a part of the second optical system and enters the eye to be examined from the same direction as the optical axis of the second optical system. Then, the second light reflected by the eye to be examined passes through at least a part of the first optical system and is received by the second imaging element. Therefore, an image of the eye to be inspected by light irradiated to the eye to be examined from the second light source is observed (photographed) by the second imaging element through at least a part of the first optical system.
In this ophthalmologic apparatus, when the eye to be examined is observed (captured) with the first imaging element, the first optical system is an illumination optical system, and the second optical system is an imaging optical system. On the other hand, when observing (photographing) the eye to be examined with the second imaging element, at least a part of the second optical system becomes an illumination optical system, and at least a part of the first optical system becomes an imaging optical system. Therefore, the optical system that is a photographing optical system differs for each photographing element. For this reason, the imaging optical system suitable for the item to be inspected with the imaging element can be configured for each imaging element. That is, the second optical system can be configured according to the inspection target item to be inspected with the first imaging element, and the first optical system can be configured according to the inspection target item to be inspected with the second imaging element.

  In one embodiment of the ophthalmologic apparatus, the light from the first light source becomes slit light and enters the cornea of the eye to be examined, and the first imaging element photographs a corneal endothelial cell image of the eye to be examined by the slit light. On the other hand, the light from the second light source becomes slit light and enters the cornea of the eye to be examined, and the second imaging element can take an image for measuring the corneal thickness of the eye to be examined. According to such an embodiment, each of corneal endothelial cells and corneal thickness can be inspected using an appropriate imaging optical system.

In the ophthalmologic apparatus according to the above-described embodiment, the optical system from the first optical system until the second light reflected by the cornea of the eye to be examined is guided to the second imaging element is configured by a telecentric optical system. preferable. According to such a configuration, the corneal thickness can be accurately measured without performing accurate focusing between the eye to be examined and the optical system.
Further, in the optical system in which the second light reflected by the cornea of the eye to be examined is guided to the second imaging element in the first optical system, the portion that receives the cornea surface image at a position conjugate with the cornea surface includes: A light amount attenuating member for attenuating the amount of incident light is preferably provided. According to such a configuration, only the amount of reflected light reflected by the corneal surface (corneal epithelium) is attenuated, and the amount of reflected light reflected by the corneal endothelium is not attenuated. For this reason, both strong light reflected by the cornea surface and weak light reflected by the corneal endothelium can be satisfactorily observed by the imaging element.

  In order to observe the eye to be examined in this type of ophthalmic apparatus, it is necessary to perform focusing (alignment) between the apparatus main body (light source, optical system and imaging element) and the eye to be examined (for example, corneal epithelium or corneal endothelium). . The present invention provides a technique capable of accurately performing alignment between an apparatus main body and an eye to be examined. The technique (alignment method) according to the present invention is an ophthalmic apparatus that examines (observes) a single examination item (that is, an ophthalmic apparatus that does not include the second light source and the second imaging element (for example, for corneal endothelial cell observation). Needless to say, the present invention can be applied to other ophthalmic devices)).

An ophthalmologic apparatus according to an embodiment that realizes the alignment method of the present invention is disposed at an equally divided position between a first optical system and a second optical system, and an anterior ocular segment observation optical system for observing the anterior ocular segment of an eye to be examined. System, a third imaging element for receiving an anterior ocular segment image of the eye to be examined guided by the anterior ocular segment observation optical system, and an XY direction from the same direction as the optical axis of the anterior ocular segment observing optical system toward the subject eye An alignment optical system that projects alignment index light, an apparatus main body on which each of the light sources, each optical system, and each imaging element is mounted; an XY direction moving unit that moves the apparatus main body in the XY direction with respect to the eye to be examined; Control means for controlling the XY direction moving means is further provided. Then, the control means drives the XY direction moving means so that the image of the XY direction alignment index light received by the third imaging element via the anterior ocular segment observation optical system is at a predetermined position. In the ophthalmologic apparatus according to this embodiment, alignment of the apparatus main body with respect to the subject's eye in the XY directions (that is, two directions orthogonal to the optical axis of the anterior ocular segment observation optical system) is performed by the control means.
The third imaging element can also be used as the first imaging element. For example, by arranging the first imaging element on the optical axis of the anterior ocular segment observation optical system, the anterior segment of the eye to be examined can be observed with the first imaging element.

The ophthalmic apparatus preferably further includes Z-direction moving means for moving the apparatus main body in the direction of the eye to be examined. The first optical system is provided with means for projecting the first Z-direction alignment index light toward the eye to be examined, and the second optical system projects the second Z-direction alignment index light toward the eye to be examined. Means are provided. The control means moves in the Z direction based on the interval between the first Z-direction alignment index light image and the second Z-direction alignment index light image received by the third imaging element via the anterior ocular segment observation optical system. It is preferable to drive the means.
In this ophthalmologic apparatus, the apparatus main body is moved in the Z direction (the direction of the eye to be examined) by utilizing the fact that the first optical system and the second optical system have a substantially specular reflection relationship with respect to the eye to be examined. That is, the reflected image of the first Z-direction alignment index light projected from the first optical system and the reflected image of the second Z-direction alignment index light projected from the second optical system are transmitted via the anterior ocular segment observation optical system. And observe with a third imaging element. If the distance (distance) between both reflected images is known, the distance in the Z direction between the eye to be examined and the apparatus main body can be known. For this reason, the control means moves the apparatus main body in the Z direction (the direction of the eye to be examined) based on the interval between the two reflection images.

In the above ophthalmologic apparatus, the control means matches the image of the first Z-direction alignment index light and the image of the second Z-direction alignment index light received by the third imaging element via the anterior ocular segment observation optical system, In addition, after the image of the Z-direction alignment index light and the image of the XY-direction alignment index light have a predetermined positional relationship, the image is received by the first imaging element while the apparatus body is further moved in the direction of the eye to be examined. The apparatus main body and the corneal endothelium of the eye to be inspected can be focused based on the contrast or luminance of the eye image to be examined by the first light source.
In this ophthalmic apparatus, first, the apparatus main body is focused on the corneal epithelium of the eye to be inspected based on the index light for XY direction alignment and the index light for Z direction alignment. Next, the apparatus main body and the corneal endothelium are focused based on the eye image received by the first imaging element while moving the apparatus main body in the direction of the eye to be examined. In other words, the corneal endothelium image of the eye to be examined can be received in the first imaging element by moving the apparatus main body to the vicinity of the position where the apparatus main body is in focus with the alignment index light. For this reason, the apparatus main body and the corneal endothelium can be focused on the basis of the corneal endothelium image received by the first imaging element. Therefore, the apparatus main body and the corneal endothelium of the eye to be examined can be focused.

The ophthalmologic apparatus further includes a Z-direction moving means for moving the apparatus main body in the direction of the eye to be examined, and the Z-direction alignment index light is directed toward the eye to be examined in the first optical system or the second optical system. Projecting means is provided, and the control means drives the Z-direction moving means based on the position of the Z-direction alignment index light image received by the third imaging element via the anterior ocular segment observation optical system. You can also.
Also in this ophthalmologic apparatus, the apparatus main body is moved in the Z direction (the direction of the eye to be examined) based on the Z-direction alignment index light projected from the first optical system or the second optical system, and alignment in the Z direction can be performed. it can.

In this case, the control means has the XY direction alignment index light image received by the third imaging element via the anterior ocular segment observation optical system at a predetermined position, and the first means via the anterior ocular segment observation optical system. After the image of the Z-direction alignment index light received by the three imaging elements reaches a predetermined position, the eye image by the first light source received by the first imaging element while further moving the apparatus body in the direction of the eye to be examined It is preferable to focus the apparatus main body and the eye to be examined based on the contrast or luminance.
Also in this ophthalmologic apparatus, the apparatus main body is focused on the vicinity of the corneal epithelium of the eye to be inspected based on the index light for XY direction alignment and the index light for Z direction alignment. Then, the apparatus main body and the corneal endothelium are focused based on the eye image received by the first imaging element while moving the apparatus main body in the direction of the eye to be inspected.

In the above-described ophthalmologic apparatus, the light from the first light source becomes slit light and enters the cornea of the eye to be examined, and the first imaging element captures a corneal endothelial cell image of the eye to be examined by the slit light, In the case of an ophthalmologic apparatus for photographing an image for measuring the corneal thickness of the eye to be examined, the light from the two light sources becomes slit light and enters the cornea of the eye to be examined. Is preferred. That is, the apparatus further includes a Z-direction moving unit that moves the apparatus main body in the direction of the eye to be examined, and the control unit is (1) XY-direction alignment index light received by the third imaging element via the anterior ocular segment observation optical system. After the image is in a predetermined position, the cornea surface and the apparatus main body are focused on the basis of the position of the cornea surface in the cornea image received by the second imaging element. (2) From the focused position Further, the apparatus main body is advanced toward the subject's eye by a predetermined amount determined from the corneal thickness obtained based on the corneal image received by the second imaging element, and (3) the apparatus main body is further moved in the direction of the subject's eye from the advanced position. It is preferable to focus the apparatus main body and the corneal endothelium of the eye to be inspected based on the contrast or brightness of the corneal image by the first light source received by the first imaging element while being moved to the position.
In this ophthalmologic apparatus, the apparatus main body and the corneal epithelium are focused based on the corneal image received by the second imaging element. Next, a predetermined amount determined from the corneal thickness obtained based on the corneal image received by the second imaging element with reference to the position where the apparatus main body and the corneal epithelium are in focus (for example, 1/2 of the obtained corneal thickness, etc. ) Move the device body in the direction of the eye to be examined. Then, while moving the apparatus main body from the position in the direction of the eye to be examined, the focus between the apparatus main body and the corneal endothelium is determined based on the eye image received by the first imaging element. Therefore, the apparatus main body can be moved to the vicinity of the position where the corneal endothelium is in focus using the corneal thickness determined from the corneal image received by the second imaging element. For this reason, focusing with the apparatus main body and a corneal endothelium can be performed in a short time.

In addition, the control means (1) after the image of the XY direction alignment index light received by the third imaging element via the anterior ocular segment observation optical system reaches a predetermined position, is then received by the second imaging element. The corneal surface and the apparatus main body are focused on the basis of the position of the corneal surface in the corneal image, and (2) the corneal thickness obtained based on the corneal image received by the second imaging element from the focused position. (3) The corneal endothelium image with the first imaging element while moving the apparatus body in the direction of the eye to be examined at a predetermined movement interval with reference to the advanced position. May be continuously shot for a predetermined number of frames.
In this ophthalmologic apparatus, after moving the apparatus main body to the vicinity of the position where the apparatus main body and the corneal endothelium are in focus, the corneal endothelium image is continuously photographed by a predetermined number of frames while moving the apparatus main body at a predetermined movement interval. Since the corneal endothelium images taken continuously include a clear image (that is, an image taken with the device main body and the corneal endothelium in focus), it is determined whether the device main body and the corneal endothelium are in focus. Even without it, the corneal endothelium image can be observed.

  Hereinafter, an ophthalmologic apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 2 is a diagram showing a schematic configuration of the ophthalmologic apparatus according to the present embodiment. As shown in FIG. 2, the ophthalmologic apparatus of this embodiment includes an apparatus main body 10 on which an optical system (detailed later) is mounted, a main control circuit 70 that controls the apparatus main body 10, and the like.

  The apparatus main body 10 is movable in the up / down / left / right direction (X / Y direction) and the front / rear direction (Z direction) with respect to the eye E of the subject whose jaw is fixed to a chin rest (not shown). . The apparatus main body 10 is moved in the vertical direction by the X-axis drive mechanism 86, moved in the left-right direction by the Y-axis drive mechanism 88, and moved in the front-rear direction by the Z-axis drive mechanism 82. The X-axis, Y-axis, and Z-axis drive mechanisms 86, 88, and 82 are equipped with stepping motors (not shown), respectively. These motors are controlled by the main control circuit 70.

The main control circuit 70 is constituted by a microcomputer provided with a CPU, ROM, RAM, I / O, and the like. The main control circuit 70 is connected to light emission control circuits 72 and 84 and an image input / output circuit 76. The main control circuit 70 controls the light sources 38 and 20 via the light emission control circuits 72 and 84, and performs processing such as capturing of images received by the imaging elements 12 and 46 via the image input / output circuit 76. A monitor 74 is connected to the image input / output circuit 76. On the monitor 74, an image photographed by the photographing elements 12 and 46 is displayed.
Further, an operation member 78 and an automatic photographing switch 80 are connected to the main control circuit 70. The operation member 78 is a member such as a joystick that is operated by an inspector. The inspector can manually move the apparatus main body 10 in the up / down / left / right direction and the front / rear direction by operating the operation member 78. The automatic photographing switch 80 is a switch operated by an inspector. When the examiner operates the automatic photographing switch 80, the main control circuit 70 automatically photographs a corneal endothelium image of the eye E to be examined.

  FIG. 1 shows a schematic configuration of an optical system mounted on the apparatus main body 10. FIG. 1 shows a state where the apparatus main body 10 is focused on the corneal endothelium 68 of the eye E. As shown in FIG. 1, the optical system mounted on the apparatus main body 10 includes an illumination optical system 60 and a photographing optical system 64 that are disposed at a position substantially in a specular reflection relationship with respect to the eye E.

The illumination optical system 60 has an optical axis O ₂ that extends obliquely toward the eye E. On the optical axis O ₂ , lenses 30 and 28, a cold mirror (or dichroic mirror) 26, a half mirror 14, and the imaging element 12 are arranged in this order from the eye E side. Illumination light emitted from the illumination light source 20 is incident on the cold mirror 26. A condenser lens 22 and a slit 24 are disposed between the illumination light source 20 and the cold mirror 26. The illumination light source 20 is a light source for photographing a corneal endothelial cell image of the eye E, and emits light having a wavelength of 500 to 600 nm. The light emitted from the illumination light source 20 first passes through the condenser lens 22 and then becomes slit light by the slit 24. The slit light is reflected by the cold mirror 26 and is irradiated obliquely toward the eye E through the lenses 28 and 30.

Light emitted from the Z-direction alignment light source 18 is incident on the half mirror 14. A slit 16 is disposed between the Z-direction alignment light source 18 and the half mirror 14. The Z-direction alignment light source 18 is a light source for performing alignment in the front-rear direction between the apparatus main body 10 and the eye E, and emits light having a wavelength of 800 to 900 nm (700 nm or more). The light emitted from the Z-direction alignment light source 18 becomes slit light by the slit 16. The slit light is reflected by the half mirror 14 and is irradiated obliquely toward the eye E through the cold mirror 26 and the lenses 28 and 30.
The slit 16 may be a pinhole plate. When the slit 16 is a pinhole plate, the light from the Z-direction alignment light source 18 becomes spot light and is irradiated to the eye E.

  The imaging element 12 is an imaging element for measuring the corneal thickness (that is, an imaging element for imaging a corneal image including both an image of the corneal epithelium 66 and an image of the corneal endothelium 68). A CCD element can be used as the imaging element 12. A corneal image by light emitted from a corneal thickness measurement light source 38 described later is guided to the imaging element 12. With the lenses 30 and 28 for guiding the corneal image to the imaging element 12, an image of the corneal epithelium 66 and an image of the corneal endothelium 68 are simultaneously captured by the imaging element 12.

FIG. 10 is a front view of the light receiving surface of the imaging element 12. As shown in FIG. 10, a light amount attenuating member 12 b is disposed on the light receiving surface of the imaging element 12. The light amount attenuating member 12b is a member (for example, an ND filter) for attenuating the amount of light incident on the light receiving surface of the imaging element 12.
FIG. 11 shows a corneal image received by the imaging element 12 when the apparatus main body 10 is focused on the corneal endothelium 68 of the eye E to be examined. As is clear from the comparison between FIG. 10 and FIG. 11, the light amount attenuating member 12 b is arranged in the region that receives the reflected image reflected by the corneal epithelium 66 and is in the region that receives the reflected image reflected by the corneal endothelium 68. Is not arranged. This is because the amount of reflected light reflected from the corneal epithelium 66 is much larger than the amount of reflected light reflected from the corneal endothelium 68. By attenuating the reflected light reflected from the corneal epithelium by the light amount attenuating member 12b, the reflected image of the corneal epithelium 66 and the reflected image of the corneal endothelium 68 can be taken clearly.

The imaging optical system 64 has an optical axis O ₃ that extends obliquely toward the eye E to be examined. On the optical axis O ₃ , a lens 32, a cold mirror (or dichroic mirror) 34, a slit 36, and a corneal thickness measurement light source 38 are disposed in this order from the eye E side. The corneal thickness measurement light source 38 is an illumination light source for capturing an eye image for corneal thickness measurement, and emits light having a wavelength of 800 to 900 nm (700 nm or more). The light emitted from the corneal thickness measurement light source 38 is converted into slit light by the slit 36, and then passes through the cold mirror 34 and the lens 32 and enters the eye E to be examined obliquely. The slit light incident on the eye E is reflected by the corneal epidermis 66 and the corneal endothelium 68 of the eye E. The reflected images reflected by the corneal epidermis 66 and the corneal endothelium 68 are magnified by the lenses 30 and 28 of the illumination optical system 60, pass through the cold mirror 26 and the half mirror 14, and are observed by the imaging element 12. Therefore, the imaging optical system 64 for observing (imaging) corneal endothelial cells functions as an illumination optical system for measuring corneal thickness, and an illumination optical system 60 for observing (imaging) corneal endothelial cells. Functions as an imaging optical system for measuring the corneal thickness.

  Light that enters the cold mirror 34 from the eye E side through the lens 32 (for example, a corneal endothelium image of the eye E by the illumination light source 20) is reflected by the cold mirror 34. The cornea image reflected by the cold mirror 34 passes through the slit 40 and the lens 42, is reflected by the upper surface of the special mirror 44, and is guided to the imaging element 46 (for example, a CCD element). The lenses 32 and 42 for guiding the corneal endothelium image to the imaging element 46 (lenses 32 and 42 arranged in the imaging optical system 62) are set to high resolution so that the cell image of the corneal endothelium 68 can be clearly observed.

  The cold mirror (or dichroic mirror) 44 reflects light having a wavelength of 700 nm or less (wavelength 500 to 600 nm in the case of a dichroic mirror) emitted from the illumination light source 20 and transmits light having a wavelength of 700 nm or more. Accordingly, the illumination light (wavelength 700 nm or more) for illuminating the eye E during observation of the anterior segment of the eye E, the light from the Z-direction alignment light source 18 and the corneal thickness measurement light source 38 pass through the cold mirror 44, Light is received by the imaging element 46. On the other hand, the light used at the time of corneal endothelial cell imaging (light from the illumination light source 20) does not enter the imaging element 46 from the anterior eye side.

An anterior ocular segment observation optical system 62 is disposed at a position where the illumination optical system 60 and the photographing optical system 64 are equally divided. Anterior segment observation optical system 62 includes a lens 61 arranged on an optical axis O _1. On the optical axis O _{1 of the} anterior ocular segment observation optical system 62, a special mirror 44 and a photographing element 46 are arranged. The anterior segment image of the eye E is guided to the imaging element 46 through the half mirror 58, the lens 61 and the special mirror 44.

In addition, the light of the XY direction alignment light source 50 and the light of the fixation lamp 52 are incident on the half mirror 58 disposed on the optical axis O ₁ . A pinhole plate 48, a half mirror 54, and a lens 56 are disposed between the XY direction alignment light source 50 and the half mirror 58. The light emitted from the XY direction alignment light source 50 becomes spot light at the pinhole plate 48. This spot light is reflected by the half mirror 54 and then passes through the lens 56. The spot light transmitted through the lens 56 is reflected by the half mirror 58 and enters the eye E from the front. Spot light reflected by the eye E (specifically, the corneal surface 66) is received by the imaging element 46 via the half mirror 58, the lens 61, and the special mirror 44.
Further, the light from the fixation lamp 52 passes through the half mirror 54 and the lens 56 and enters the half mirror 58. The light of the fixation lamp 52 that has entered the half mirror 58 is reflected by the half mirror 58 and enters the eye E to be examined. The light from the fixation lamp 52 is used to fix the viewpoint of the subject.

Next, one procedure for measuring the corneal thickness of the eye E using the above-described ophthalmic apparatus and photographing corneal endothelial cells will be described. FIG. 3 is a flowchart showing an example of processing for automatically measuring corneal thickness and photographing corneal endothelial cells.
When the subject fixes the chin to the chin rest and is ready for examination, the examiner turns on the power of the ophthalmologic apparatus (S10). When the power is turned on, the main control circuit 70 displays the anterior segment image of the eye E on the monitor 74 (S12). That is, the anterior segment image of the subject eye E received on the light receiving surface of the imaging element 46 is displayed on the monitor 74. When the anterior segment image is displayed on the monitor 74, the examiner operates the automatic photographing switch 80, whereby the main control circuit 70 starts processing after step S14 (automatic photographing processing).

In the automatic photographing process, first, the main control circuit 70 turns on the light source 50 for XY-direction alignment (S14). When the XY direction alignment light source 50 is turned on, the XY direction alignment index light enters the eye E. The XY direction alignment index light reflected by the eye E is observed by the imaging element 46 via the anterior segment observation optical system 62.
Next, the main control circuit 70 drives the X-axis drive mechanism 86 and the Y-axis drive mechanism 88 so that the XY-direction alignment index light incident on the light-receiving surface of the imaging element 46 is at a predetermined position on the light-receiving surface. (S16). As a result, the apparatus main body 10 moves in the XY directions, and alignment of the eye E to be examined and the apparatus main body 10 in the XY directions is performed. In the state in which the alignment in the XY directions is performed, a bright spot of the index light for XY direction alignment is observed at a predetermined position in the anterior segment image displayed on the monitor 74 (for example, approximately the center of the anterior segment image). .

  When the alignment of the apparatus main body 10 in the X and Y directions is completed, the main control circuit 70 turns on the Z direction alignment light source 18 and the corneal thickness measurement light source 38 (S18). As a result, the slit light from the Z-direction alignment light source 18 and the slit light from the corneal thickness measurement light source 38 enter the cornea of the eye E to be examined. A part of these slit lights is reflected by the corneal epithelium 66, and the reflected image is received by the imaging element 46 via the anterior ocular segment observation optical system 62.

Next, the main control circuit 70 performs processing for focusing the apparatus body 10 on the corneal endothelium of the eye E (S20). The corneal endothelium focusing process by the main control circuit 70 will be described with reference to the flowchart shown in FIG.
In the corneal endothelium focusing process, first, the main control circuit 70 determines the Z-axis drive mechanism based on the interval between the slit image by the Z-direction alignment light source 18 and the slit image by the corneal thickness measurement light source 38 observed by the imaging element 46. 82 is driven to perform alignment in the Z direction between the apparatus main body 10 and the eye E (S32). The alignment in the Z direction in step S32 will be specifically described with reference to FIGS.

As shown in FIG. 5, the position (the corneal epithelium in the figure is closer to the eye E) than the position where the apparatus body 10 is in focus with the corneal epithelium 66 of the eye E (the position where the corneal epithelium is indicated by 66b in the figure). The slit light from the Z-direction alignment light source 18 is reflected at the position of the point B1 of the corneal epithelium 66a, and the slit light from the corneal thickness measuring light source 38 at the point A1 of the corneal epithelium 66a. Reflected at position. FIG. 6 schematically shows an anterior ocular segment image observed with the imaging element 46 at this time. As is clear from FIG. 6, a bright spot 96 of the XY direction alignment index light is observed at the approximate center of the eye E (cornea K), and a slit image 94 by the Z direction alignment light source 18 is located on the left side of the bright spot 96. However, a slit image 92 is observed on the right side of the bright spot 96 by the corneal thickness measurement light source 38.
On the other hand, when the apparatus main body 10 is at a position where the corneal epithelium 66 of the eye E is in focus (a position where the corneal epithelium is indicated by 66b), the slit light from the Z-direction alignment light source 18 and the corneal thickness measurement light source 38 are used. The slit light is reflected at a point A0 (B0) on the corneal surface 66b (see FIG. 5). Therefore, in the anterior segment image observed by the imaging element 46, the bright spot 96 of the XY direction alignment index light, the slit image 94 by the Z direction alignment light source 18, and the slit image 92 by the corneal thickness measurement light source 38 are obtained. Are observed at the same position (see FIG. 7).
When the apparatus main body 10 is at a position away from the position where the apparatus main body 10 is focused on the corneal epithelium 66 of the eye E (the position where the corneal epithelium is indicated by 66c in the figure), the slit light from the Z-direction alignment light source 18 is The slit light from the corneal epithelium 66c is reflected at the point B3, and the slit light from the corneal thickness measuring light source 38 is reflected at the point A3 in the corneal epithelium 66c. Therefore, in the anterior segment image observed by the imaging element 46, the slit image 94 by the Z direction alignment light source 18 is observed on the right side of the bright spot 96 of the XY direction alignment index light, and the corneal thickness is on the left side of the bright spot 96. A slit image 92 by the measurement light source 38 is observed.
As is clear from the above description, the positions of the slit image 94 by the Z-direction alignment light source 18 and the slit image 92 by the corneal thickness measurement light source 38 (the distance between them) observed by the imaging element 46 are The distance to the eye E can be measured. In step S32, the Z-axis drive mechanism 82 is driven based on the interval between the slit image 94 by the Z-direction alignment light source 18 and the slit image 92 by the corneal thickness measurement light source 38 observed by the imaging element 46, and the apparatus main body 10 is moved. The corneal epithelium 66 of the eye E is focused.

  In the above description, the bright spot 96 of the XY direction alignment index light, the slit image 94 by the Z direction alignment light source 18, and the slit image 92 by the corneal thickness measurement light source 38 are located at the same position on the imaging element 46. In this example, the apparatus body 10 and the corneal epithelium 66 are in focus when observed. However, the present invention is not limited to such an example. For example, when the slit image 94 observed by the photographing element 46 by the Z-direction alignment light source 18 and the slit image 92 by the corneal thickness measurement light source 38 coincide with each other, the slit image 94 (slit image 92) and the XY-direction alignment are used. The optical systems 60, 62, and 64 can be adjusted so that the bright spot 96 of the index light has a predetermined positional relationship. For example, as shown in FIG. 8, when the slit image 94 by the Z-direction alignment light source 18 and the slit image 92 by the corneal thickness measurement light source 38 coincide with each other, the slit image 94 (slit image 92) is used for the XY-direction alignment. Adjustment is made so that the bright spot 96 of the index light is observed on the right side. By adjusting in this way, the apparatus main body 10 and the corneal epithelium 66 can be substantially focused only by matching the slit image 94 by the Z-direction alignment light source 18 and the slit image 92 by the corneal thickness measurement light source 38. Can do.

  When step S32 described above is completed, next, the main control circuit 70 captures an anterior segment image of the eye E (step S34 in FIG. 4). That is, the anterior segment image of the eye E is captured by the imaging element 46. When the anterior segment image is captured in step S34, it is preferable that the Z-direction alignment light source 18 and the corneal thickness measurement light source 38 are turned off and only the XY-direction alignment light source 50 is turned on. Thus, the anterior segment image captured by the imaging element 46 includes the bright spot 96 of the index light for XY direction alignment.

  When the anterior segment image of the eye E is captured in step S34, the Z-direction alignment light source 18, the corneal thickness measurement light source 38, and the XY-direction alignment light source 50 are turned off, and only the illumination light source 20 is turned on. As a result, the imaging element 46 can capture a corneal endothelium image of the eye E. Next, the main control circuit 70 moves the apparatus body 10 toward the eye to be examined by a predetermined distance (for example, one step of the stepping motor of the Z-axis drive mechanism 82) (S36). Then, it is determined whether or not the position where the light quantity is maximized in the corneal endothelium image of the eye E received by the imaging element 46 is a preset position (S38). That is, the light amount distribution of the corneal endothelium image received by the imaging element 46 (light amount distribution from the corneal epithelium 66 toward the corneal endothelium 68) has a peak (maximum value) on the corneal endothelium surface as shown in FIG. Yes. In step S38, the position of the corneal endothelium surface is determined from the light intensity distribution (that is, luminance or contrast) of the corneal endothelium image received by the imaging element 46, and the corneal endothelium surface is determined at a predetermined position (that is, the apparatus main body 10 and the corneal endothelium). It is determined whether or not the position 68 is in focus. If NO in step S38, the process returns to step S36 and the processing from step S36 is repeated. On the other hand, if step S38 is YES, the corneal endothelium focusing process is terminated.

When the corneal endothelium focusing process is completed, the process returns to step S22 in FIG. 3, and the main control circuit 70 takes a corneal endothelial cell image. Specifically, the main control circuit 70 takes a corneal endothelium image received by the imaging element 46 and stores it in a storage area in the main control circuit 70. FIG. 12 schematically shows a corneal endothelium image photographed by the photographing element 46.
When the photographing of the corneal endothelium image is completed, the main control circuit 70 turns off the illumination light source 20 and turns on the corneal thickness measurement light source 38, and the corneal image (corneal epithelial image and corneal endothelium image) of the eye to be examined by the imaging element 12. Is taken) (S24). The photographed cornea image is stored in a storage area in the main control circuit 70.

  In step S26, the anterior segment image taken during the corneal endothelium focusing process in step S20, the corneal endothelial cell image taken in step S22 (see FIG. 12), and the corneal image taken in step S24 (see FIG. 11). Is displayed on the monitor 74. As is apparent from FIGS. 11 and 12, only the corneal endothelium image is included in the image captured in step S22, and the corneal endothelial image and the corneal epithelial image are included in the image captured in step S24. . In addition, since the image image | photographed by step S24 contains a corneal endothelium image and a corneal epithelium image, corneal thickness can be calculated from this image.

As described above, in the ophthalmologic apparatus of the present embodiment, the illumination optical system 60 for photographing a corneal endothelial cell image functions as a photographing optical system for measuring the corneal thickness. The imaging optical system 64 for imaging corneal endothelial cells functions as an illumination optical system for measuring the corneal thickness. Therefore, each of the corneal endothelial cell image and the corneal image for measuring the corneal thickness can be taken with an appropriate optical system.
In the ophthalmologic apparatus of the present embodiment, the reflection image 94 from the corneal epithelium of the slit light of the Z-direction alignment light source 18 projected from the illumination optical system 60 side and the corneal thickness measurement projected from the imaging optical system 64 side are provided. The reflected image 92 from the corneal epithelium of the slit light of the light source 38 is received by the imaging element 46 via the anterior ocular segment observation optical system 62, and the apparatus main body 10 is set so that the two reflected images 92 and 94 are made coincident. Move in the Z direction. As a result, since the apparatus main body 10 is focused on the corneal surface, the corneal image observed by the imaging element 46 includes the peak of the corneal endothelium surface. For this reason, the apparatus main body 10 can be focused on a corneal endothelium using this. Therefore, the apparatus main body 10 can be focused on the corneal endothelium without using a focusing sensor such as a line sensor that has been conventionally required.

  In the above-described embodiment, the slit light of the Z-direction alignment light source 18 projected from the illumination optical system 60 side and the slit light of the corneal thickness measurement light source 38 projected from the photographing optical system 64 side are used. The apparatus main body 10 was focused on the corneal surface of the eye E to be examined. However, the apparatus main body 10 can be focused on the cornea surface of the eye E using only one slit light projected from the illumination optical system 60 side or the photographing optical system 64 side. For example, as shown in FIGS. 13 to 16, the apparatus main body 10 is focused on the corneal surface of the eye E using only the slit light of the Z-direction alignment light source 18 projected from the illumination optical system 60 side. Can do. That is, as shown in FIG. 13, when the slit image 94 is observed on the left side of the bright spot 96 of the index light for XY alignment, the apparatus main body 10 is too close to the eye E, and as shown in FIG. When the slit image 94 is observed on the right side of the bright spot 96 of the index light for XY direction alignment, the apparatus main body 10 is too far from the eye E, and the index light for XY direction alignment is shown in FIG. The bright spot 96 and the slit image 94 coincide with each other when the apparatus main body 10 is focused on the corneal surface. For this reason, the apparatus body 10 is moved in the Z direction according to the position of the slit image 94 received by the imaging element 46, and the slit image 94 received by the imaging element 46 and the bright spot 96 of the index light for XY direction alignment are obtained. By matching, the apparatus main body 10 can be focused on the corneal surface of the eye E to be examined.

  As mentioned above, although some embodiment of this invention was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

By configuring the illumination optical system of the ophthalmologic apparatus as a telecentric optical system, the cornea from the cornea image received by the imaging element 12 without the apparatus body 10 being accurately focused on the corneal endothelium 66 of the eye E to be examined. The thickness can be determined accurately. For example, as shown in FIG. 18, the eye side of the illumination optical system is configured as a telecentric optical system.
In the example illustrated in FIG. 18, the half mirror 112 is disposed on the optical axis O ₂ of the illumination optical system 60, and the light reflected by the half mirror 112 is guided to the imaging element 116. A stop 114 is disposed on the optical axis of the lens 30 and the imaging element 116. Then, the distance from the lens 30 to the diaphragm 114 is adjusted to the focal length of the lens 30.
In this configuration, the relationship between the position of the eye E and the cornea image observed by the imaging element 116 will be described with reference to FIG. In FIG. 19, the correct focus position of the eye E with respect to the lens 30 is P _0, and the focus position of the imaging element 116 when the lens 30 is placed at the correct focus position P ₀ is P ₀ ′. The optical axis a is the optical axis of the reflected light reflected by the corneal epithelium 66, and the optical axis b is the optical axis of the reflected light reflected by the corneal endothelium 68.
In the case shown in FIG. 19, in the reflected light reflected by the corneal epithelium 66, only the light component (light indicated by “a” in the drawing) perpendicularly incident on the lens 30 passes through the diaphragm 114 and is guided to the imaging element 116. In addition, the reflected light reflected by the corneal endothelium 68 is also guided to the imaging element 116 only by the light component (light indicated by b in the figure) that enters the lens 30 perpendicularly.
When the eye E shifts from the focus position P ₀ to the front and rear positions P ₁ and P ₂ , the focus position of the imaging element 116 also shifts to P ₁ ′ and P ₂ ′. Therefore, if the imaging element 116 is placed at the point P ₀ ′, the imaging element 116 is not brought into focus. However, even when the subject eye E shifts from the focus position P ₀ to the front and rear positions P ₁ and P ₂ , the reflection image of the corneal epithelium 66 and the reflection of the corneal endothelium 68 observed by the imaging element 116 disposed at the point P ₀ ′. The image spacing does not change. As a result, the corneal thickness of the eye E can be accurately calculated from the cornea image captured by the imaging element 116.

  Note that a light amount attenuation member 116b is preferably disposed on the light receiving surface of the imaging element 116 as shown in FIG. The light amount attenuating member 116b is disposed in a region where a reflected image reflected by the corneal epithelium 66 is captured (that is, a position conjugate with the corneal epithelium 66). As a result, both the reflected image of the corneal epithelium 66 and the reflected image of the corneal endothelium 68 can be clearly photographed by the imaging element 116.

Furthermore, as a special case, when the imaging element 12 is movable, as shown in FIG. 16, the illumination optical system is configured by both telecentric optical systems, so that the apparatus main body 10 can be accurately placed on the corneal endothelium 66 of the eye E to be examined. Even without focusing, the corneal thickness can be accurately obtained from the corneal image received by the imaging element 12.
This will be specifically described. As shown in FIG. 16, a diaphragm 100 is disposed between the lens 30 and the lens 28. The distance from the lens 30 to the aperture 100 is set as the focal length f ₁ of the lens 30 (l ₁ in the drawing), and the distance from the aperture 100 to the lens 28 is adjusted to the focal length f ₂ of the lens 28 (l ₂ in the drawing). To do. According to such a configuration, only the light incident perpendicularly to the lens 30 out of the light incident on the lens 30 (the light a reflected by the corneal epithelium 66 and the light b reflected by the corneal endothelium 68) is allowed to enter the diaphragm 100. It passes through and is guided to the lens 28. The light guided to the lens 28 is guided to the imaging element 12 by the lens 28 as a parallel light beam. Therefore, even if the lens 30 (that is, the apparatus main body 10) cannot be adjusted to the correct focus position with respect to the eye E, the distance between the corneal epithelium 66 and the corneal endothelium 68 observed by the imaging element 12 is the same. . Therefore, the corneal thickness of the eye E can be accurately obtained without accurately focusing the apparatus body 10 on the eye E.

This will be described with reference to FIG. In FIG. 17, an accurate focus position of the eye E with respect to the lens 30 is P _0, and an accurate focus position of the imaging element 12 with respect to the lens 28 is P ₀ ′. The optical axis a is the optical axis of the reflected light reflected by the corneal epithelium 66, and the optical axis b is the optical axis of the reflected light reflected by the corneal endothelium 68.
In FIG. 17, the diaphragm 100 is disposed at a position separated from the lens 30 by the focal length f ₁ (l ₁ ) of the lens 30. For this reason, in the reflected light reflected by the corneal epithelium 66, only the light component (light indicated by a in the drawing) perpendicularly incident on the lens 30 passes through the diaphragm 100 and is guided to the imaging element 12. Further, only the light component (light indicated by b in the figure) that is perpendicularly incident on the lens 30 is guided to the imaging element 12 from the reflected light reflected by the corneal endothelium 68. Even if the eye E shifts from the focus position P ₀ to the front and rear positions P ₁ and P ₂ , the distance between the light component a and the light component b does not change. For this reason, the reflected images (images of the corneal epithelium 66 and the corneal endothelium 68) observed by the imaging element 12 are at the same interval.
The lens 28 is disposed at a position away from the stop 100 by the focal length f ₂ (l ₂ ) of the lens 28. Therefore, the light passing through the diaphragm 100 and passing through the lens 28 is guided to the image sensor 12 as a parallel light flux. For this reason, even if the imaging element 12 is shifted from the focus position P ₀ ′ to the front and rear positions P ₁ ′ and P ₂ ′, the interval between the reflected images observed by the imaging element 12 is the same. Thereby, the imaging element 12 with respect to the lens 28 may be movable.
In the object-side telecentric optical system shown in FIG. 18 described above, the half mirror 112 is disposed between the lens 30 and the lens 28, and the light reflected by the half mirror 112 is guided to the imaging element 116. However, the object-side telecentric system can also be configured by the arrangement of the optical system as shown in FIG. That is, in the configuration shown in FIG. 16, the distance l ₂ from the stop 100 to the lens 28 may be different from the focal length f ₂ of the lens 28.

Further, unlike the above-described embodiment, a corneal endothelial cell image of the eye E can be taken without focusing the apparatus body 10 on the corneal endothelium 68. Processing performed in the main control circuit 70 in such a case will be described with reference to FIG. Also in FIG. 21, it is assumed that the processing from steps S10 to S16 in FIG. 3 is performed.
As shown in FIG. 21, when the alignment of the apparatus main body 10 in the X and Y directions with respect to the eye E is completed in step S16 of FIG. 3, the main control circuit 70 focuses the apparatus main body 10 on the corneal epithelium 66 of the eye E ( S39). The apparatus body 10 can be focused on the corneal epithelium 66 by observing a corneal image of the slit light of the corneal thickness measuring light source 38 with the imaging element 12. As already described, the corneal image received by the imaging element 12 includes an image reflected by the corneal epithelium 66 and an image reflected by the corneal endothelium 68. Therefore, the light amount distribution of the cornea image received by the imaging element 12 (light amount distribution in the depth direction of the cornea) is as shown in FIG. That is, in the light amount distribution of the corneal image, a peak (maximum value) indicating the position of the corneal epithelium 66 and a peak (maximum value) indicating the position of the corneal endothelium 68 are observed. Therefore, the main control circuit 70 drives the Z-axis drive mechanism 82 so that the peak value indicating the corneal surface 68 is a predetermined position (that is, the position where the apparatus main body 10 and the corneal epithelium 66 are in focus). The main body 10 is moved in the Z direction.

  When the apparatus main body 10 is focused on the corneal epithelium 66 of the eye E, the main control circuit 70 next measures the corneal thickness of the eye E (S40). The corneal thickness is measured by taking a slit image of the eye E to be examined by the corneal thickness measuring light source 38 with the imaging element 12 and calculating the corneal thickness from the image. Specifically, the position representing the corneal epithelium and the position representing the corneal endothelium are identified from the light quantity distribution of the obtained image, and the corneal thickness is calculated from the interval between the two (see FIG. 22). In addition, by adopting a telecentric optical system for the illumination optical system 60, the corneal thickness of the eye E can be accurately obtained. That is, as shown in FIG. 22, t1 and t2 indicating the corneal thickness do not change depending on the position of the eye E (t1 = t2).

  When the corneal thickness is calculated in step S40, it is determined how much the apparatus main body 10 is to be moved from the calculated corneal thickness (S42). That is, from the current position (position where the apparatus main body 10 is focused on the corneal epithelium 66), the position where the apparatus main body 10 can reliably focus on the corneal endothelium 68 (ie, further forward from the focused position toward the eye E). The amount of movement up to The amount of movement of the apparatus main body 10 can be determined in consideration of the measurement error of the corneal thickness measured in step S40. For example, a value obtained by multiplying the corneal thickness measured in step S40 by a predetermined value x (x is a numerical value of 1.0 or more (for example, 1.1)) can be used. When the predetermined value x is set to a value exceeding 1.0, the apparatus main body 10 goes beyond the position where the apparatus main body 10 is focused on the corneal endothelium 68 of the eye to be examined even if there is an error in the corneal thickness measured in step S40. Will approach. For this reason, an image photographed in a state where the apparatus main body 10 is in focus with the corneal endothelium 68 is included in the image photographed in step S48 described later.

  Next, the main control circuit 70 moves the apparatus main body 10 toward the eye E by 1/2 of the total movement amount determined in step S42 (S44). Note that the amount of movement of the apparatus main body 10 in step S44 does not necessarily have to be ½ of the total amount of movement determined in step S42, and can be determined as appropriate in consideration of a measurement error of the corneal thickness.

In step S46, the main control circuit 70 moves the apparatus main body 10 toward the eye to be examined by a predetermined distance (for example, one step of the stepping motor of the Z-axis drive mechanism 82). Then, the corneal endothelium image of the eye E to be examined by the illumination light source 20 is photographed by the photographing element 46 (S48), and the movement amount from the reference position where the apparatus main body 10 is focused on the corneal epithelium 66 is determined in step S42. It is determined whether or not the movement amount has been reached (S50).
If the movement amount of the apparatus main body 10 is not the total movement amount determined in step S42 (NO in step S50), the process returns to step S46 and the processing from step S46 is repeated. As a result, every time the apparatus main body 10 is moved by a predetermined distance, the corneal endothelium image of the eye E is continuously photographed.

On the other hand, when the movement amount of the apparatus main body 10 becomes the total movement amount determined in step S42 (YES in step S50), an appropriate one is selected from a plurality of images taken by repeating step S48. (S52). As a method of selecting an image, for example, the position of the corneal endothelium is specified by measuring the contrast or brightness of each image, and it is determined whether or not the specified position of the corneal endothelium is an appropriate position. Can do. Alternatively, each image can be displayed on the monitor 74 and selected by the inspector.
When the image selection is completed, the selected image is stored in the storage area of the main control circuit 70 (S54). Then, an anterior segment image captured separately (for example, an anterior segment image captured at the time when the alignment of the apparatus body 10 in the X and Y directions is completed, or when the apparatus body 10 is focused on the corneal epithelium). The anterior ocular segment image) and the corneal endothelial cell image stored in step S54 are displayed on the monitor 74 (S56).

According to such an embodiment, since the focus between the eye E to be examined and the corneal endothelium 68 is not determined during imaging, the examination can be completed promptly. As a result, the burden and pain on the subject can be reduced.
Moreover, in this embodiment, the apparatus main body 10 is moved to the vicinity of the position which focuses on the corneal endothelium using the measured corneal thickness without photographing. Therefore, since the corneal endothelium image is continuously photographed only in the vicinity of the corneal endothelium focusing position, the examination time can be shortened.
Also in the above-described example, after the apparatus main body 10 is advanced toward the eye E in step S44, the focus of the apparatus main body 10 and the corneal endothelium 68 may be determined while the apparatus main body 10 is advanced. . In this case, a corneal endothelium image may be taken only when the apparatus main body 10 and the corneal endothelium 68 are in focus.

  Moreover, each optical system of the above-described ophthalmic apparatus can be implemented in variously modified or changed forms. For example, the corneal thickness measurement light source arranged on the photographing optical system 64 side can be arranged at the position of the light source 102 shown in FIG.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

It is a figure which shows schematic structure of the optical system of the ophthalmic apparatus which concerns on one Embodiment of this invention. It is a block diagram which shows the whole structure of the ophthalmologic apparatus of this embodiment. It is a flowchart of the process performed by the main control circuit. It is a flowchart of a corneal endothelium focusing process. It is a figure for demonstrating the change of the position of the slit image in an anterior ocular segment image, when the position of the apparatus main body with respect to a to-be-tested eye changes. It is a figure which shows an example of the anterior segment image observed when performing alignment of Z direction. It is a figure which shows the anterior eye part image observed when an apparatus main body focuses on the cornea surface of a to-be-tested eye. It is a figure which shows an example of the anterior ocular segment image observed in the modification of this embodiment. It is a figure which shows typically the example of the light quantity distribution of the corneal endothelium image observed with the imaging element for corneal endothelium observation. It is a front view which shows the light-receiving surface of the imaging element for a corneal thickness measurement. It is a figure which shows typically the cornea image image | photographed with the imaging element for corneal thickness measurement. It is a figure which shows typically the cornea image image | photographed with the imaging element for corneal endothelium observation. In the modification of this embodiment, it is a figure which shows an example of the anterior ocular segment image observed when performing alignment of a Z direction. In the modification of this embodiment, it is a figure which shows the other example of the anterior segment image observed when performing the alignment of a Z direction. In the modification of this embodiment, it is a figure which shows an example of the anterior segment image observed when an apparatus main body focuses on the cornea surface of a to-be-tested eye. It is a figure which shows schematic structure of the optical system of the ophthalmologic apparatus which concerns on the modification of this embodiment. It is a figure for demonstrating the effect | action of the optical system shown in FIG. It is a figure which shows schematic structure of the optical system of the ophthalmologic apparatus which concerns on the other modification of this embodiment. It is a figure for demonstrating an effect | action of the optical system shown in FIG. It is a figure for demonstrating the preferable form of the optical system shown in FIG. It is a flowchart which shows the other procedure which image | photographs a corneal endothelial cell image in the ophthalmic apparatus of this embodiment. It is a figure which shows typically light quantity distribution of the cornea image observed with the imaging element for corneal film thickness measurement. It is a figure which shows the example which changed the structure of the optical system of the ophthalmologic apparatus of this embodiment partially.

Explanation of symbols

10. .Main body 12 ..Image sensor 14 ..Mirror 16 ..Slit 18 ..Z-direction alignment light source 20 ..Light source 22 ..Condenser lens 24 ..Slit 26 ..Mirror 28 .. Lens 30 · · Lens 32 · · Lens 34 · · Mirror 36 · · Slit 38 · · Light source 40 for corneal thickness measurement · · Slit 42 · · Lens 44 · · Special mirror 46 · · Imaging element 48 · · Spot 50 · · XY direction Alignment light source 52 .. Fixation lamp 54.. Mirror 56.. Lens 58.. Mirror 60.. Illumination engineering system 62. Corneal endothelium 70. Main control circuit 74 Monitor 76 Image input / output circuit 78 Operation member 80 Automatic imaging switch 82 Z-axis drive mechanism 86 X-axis drive mechanism 8 ·· Y-axis drive mechanism

Claims (11)

A first light source;
A first optical system for irradiating the first light from the first light source obliquely toward the eye to be examined;
A second optical system arranged in a substantially specular reflection relationship with the first optical system, through which the first light reflected by the eye to be examined passes;
A first imaging element that receives the first light that has passed through the second optical system;
A second light source disposed on the second optical system side;
A second imaging element disposed on the first optical system side,
The second light from the second light source passes through at least a part of the second optical system and enters the eye to be examined from the same direction as the optical axis of the second optical system,
The second light reflected by the eye to be examined is received by the second imaging element through at least a part of the first optical system.   The light from the first light source becomes slit light and enters the cornea of the eye to be examined. The first imaging element photographs a corneal endothelial cell image of the eye to be examined by the slit light, while the light from the second light source is the slit light. 2. The ophthalmic apparatus according to claim 1, wherein the second imaging element captures an image for measuring the corneal thickness of the eye to be examined.   3. The ophthalmologic according to claim 2, wherein an optical system of the first optical system until the second light reflected by the cornea of the eye to be examined is guided to the second imaging element is a telecentric optical system. apparatus.   In the optical system in which the second light reflected from the cornea of the eye to be examined is guided to the second imaging element in the first optical system, incident light is incident on a portion that receives the cornea surface image at a position conjugate with the cornea surface. The ophthalmic apparatus according to claim 3, wherein a light amount attenuating member for attenuating the amount of light is disposed. An anterior ocular segment observation optical system for observing the anterior ocular segment of the eye to be examined, which is arranged at an equal position between the first optical system and the second optical system;
A third imaging element for receiving an anterior ocular segment image of the eye to be examined guided by the anterior ocular segment observation optical system;
An alignment optical system that projects alignment index light in the XY directions from the same direction as the optical axis of the anterior ocular segment observation optical system toward the eye to be examined;
An apparatus main body on which each of the light sources, each optical system, and each imaging element is mounted;
XY direction moving means for moving the apparatus main body in the XY direction with respect to the eye to be examined;
A control means for controlling the XY direction moving means;
The control means drives the XY direction moving means so that the image of the XY direction alignment index light received by the third imaging element via the anterior ocular segment observation optical system is at a predetermined position. The ophthalmic apparatus according to Item 1. Further comprising a Z-direction moving means for moving the apparatus body in the direction of the eye to be examined;
The first optical system is provided with means for projecting the first Z-direction alignment index light toward the eye to be examined.
The second optical system is provided with means for projecting the second Z-direction alignment index light toward the eye to be examined.
The control means moves in the Z direction based on the interval between the first Z-direction alignment index light image and the second Z-direction alignment index light image received by the third imaging element via the anterior ocular segment observation optical system. 6. The ophthalmic apparatus according to claim 5, wherein the means is driven.   The control means matches the image of the first Z-direction alignment index light received by the third imaging element via the anterior ocular segment observation optical system and the image of the second Z-direction alignment index light, and these Z directions. After the alignment index light image and the XY-direction alignment index light image have a predetermined positional relationship, the apparatus body is further moved in the direction of the eye to be inspected, and the image is received by the first light source received by the first imaging element. The ophthalmic apparatus according to claim 6, wherein the apparatus main body and the corneal endothelium of the eye to be inspected are focused on the basis of the contrast or luminance of the optometry image. Further comprising a Z-direction moving means for moving the apparatus body in the direction of the eye to be examined;
The first optical system or the second optical system is provided with means for projecting the Z-direction alignment index light toward the eye to be examined.
The control means drives the Z-direction moving means based on the position of the Z-direction alignment index light image received by the third imaging element via the anterior ocular segment observation optical system. An ophthalmic device according to claim 1.   The control means is configured such that the image of the index light for XY direction alignment received by the third imaging element via the anterior ocular segment observation optical system is in a predetermined position, and the third imaging element via the anterior ocular segment observation optical system. After the image of the Z-direction alignment index light received at is in a predetermined position, the contrast of the eye image by the first light source received by the first imaging element while further moving the apparatus main body in the eye direction or The ophthalmologic apparatus according to claim 8, wherein the apparatus main body and the eye to be examined are focused based on luminance. The light from the first light source becomes slit light and enters the cornea of the eye to be examined. The first imaging element photographs a corneal endothelial cell image of the eye to be examined by the slit light, while the light from the second light source is the slit light. In the ophthalmologic apparatus according to claim 5, wherein the second imaging element captures an image for measuring the corneal thickness of the eye to be examined.
Further comprising a Z-direction moving means for moving the apparatus body in the direction of the eye to be examined;
(1) After the image of the XY direction alignment index light received by the third imaging element via the anterior ocular segment observation optical system reaches a predetermined position, the control means receives the image by the second imaging element. Based on the position of the corneal surface in the corneal image, the corneal surface and the apparatus main body are focused. (2) From the corneal thickness obtained from the focused position and based on the corneal image received by the second imaging element. The apparatus main body is advanced toward the eye to be examined by a predetermined amount determined. (3) The corneal image of the first light source received by the first imaging element while moving the apparatus main body toward the eye to be examined further from the advanced position. An ophthalmic apparatus characterized in that focusing is performed between the apparatus main body and the corneal endothelium of an eye to be examined based on contrast or luminance. The light from the first light source becomes slit light and enters the cornea of the eye to be examined. The first imaging element photographs a corneal endothelial cell image of the eye to be examined by the slit light, while the light from the second light source is the slit light. In the ophthalmologic apparatus according to claim 5, wherein the second imaging element captures an image for measuring the corneal thickness of the eye to be examined.
Further comprising a Z-direction moving means for moving the apparatus body in the direction of the eye to be examined;
(1) After the image of the XY direction alignment index light received by the third imaging element via the anterior ocular segment observation optical system reaches a predetermined position, the control means receives the image by the second imaging element. Based on the position of the corneal surface in the corneal image, the corneal surface and the apparatus main body are focused. (2) From the corneal thickness obtained from the focused position and based on the corneal image received by the second imaging element. The apparatus main body is advanced toward the eye to be examined by a predetermined amount determined. (3) A corneal endothelium image is captured by the first imaging element while the apparatus main body is moved in the direction of the eye to be examined at a predetermined movement interval with reference to the advanced position. An ophthalmic apparatus that continuously shoots a predetermined number of frames.

Images