JP3617705B2 - Corneal endothelial cell imaging device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a corneal endothelial cell imaging apparatus that observes and images corneal endothelial cell images.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a corneal endothelial cell imaging apparatus (ophthalmic apparatus) that observes and images a corneal endothelial cell image is known. In such an ophthalmologic apparatus, the anterior ocular segment image of the eye to be examined is displayed on the screen by the anterior ocular segment observation optical system, and the front and rear direction of the eye to be examined and the apparatus based on information from the alignment detection means while viewing the anterior ocular segment image After performing the above alignment and the vertical / horizontal alignment, the corneal endothelial cell image is photographed.
[0003]
By the way, in order to take a corneal endothelial cell image in this way, it is desirable to perform alignment on the surface of the corneal endothelium (endothelium of the eye cornea to be examined).
[0004]
As an alignment detection method in the front-rear direction for this purpose, illumination light is irradiated from an oblique direction toward the subject's eye and reflected by the corneal epidermis (the subject's cornea's epidermis) and the corneal endothelium (the subject's eye cornea's endothelium), The reflected light from the corneal epidermis and corneal endothelium is received from an oblique direction substantially symmetric with respect to the optical axis of the eye to be examined, and the distance between the subject eye and the device from the position of the reflected light from the corneal endothelium of the two reflected lights. A method of obtaining information is known.
[0005]
[Problems to be solved by the invention]
In conventional vertical / horizontal alignment detection, target light is projected onto the subject's eye from the front and reflected by the subject's eye cornea, and the reflected image from the subject's eye cornea is received by PSD or the like, and the image position is detected. A method of obtaining information on the relative positional relationship between the eye to be examined and the apparatus is known.
[0006]
However, in the vertical and horizontal alignment detection by the above method, the reflectance on the corneal surface is about 100 times higher than the reflectance on the corneal endothelium, so that it is impossible to detect the reflected image from the corneal endothelium. The detected reflection image is from the corneal surface.
[0007]
For this reason, in order to perform vertical / horizontal alignment with respect to the corneal surface regardless of the device that observes / photographs corneal endothelial cell images, even if alignment is performed based on information provided from the device, endothelial cells It was not the best state for observing and photographing images, and there were problems that photographing was not successful and alignment was difficult.
[0008]
Accordingly, the present invention provides a corneal endothelial cell imaging device that can perform corneal endothelial cell image observation and imaging in the best state by performing vertical and horizontal alignment on the corneal endothelium as well as the front-rear direction. It is the purpose.
[0009]
[Means for Solving the Problems]
To this end, the invention of claim 1 includes a target projecting optical system for projecting a target light from an oblique direction with respect to the eye, and the visual target projecting optical system with respect to the subject's eye optical axis the reflected light from the cornea endothelium surface of and disposed substantially symmetrical direction the target light is received by the two-dimensional CCD, the cornea comprising an alignment detection optical system for detecting a relative positional relationship between the device and the eye to be examined In the endothelial cell imaging device, the target projection optical system is a pair of first and second target projection optical systems provided symmetrically with respect to the optical axis of the eye to be examined, and the alignment detection optical system is the test target optical system. A pair of first and second alignment detection optical systems provided symmetrically with respect to the optical axis of the eye, and a device and corneal endothelial cells based on the output of the two-dimensional CCD of the first and second alignment detection optical systems Alignment to calculate relative position to the surface Wherein the detection circuit is provided.
[0010]
In order to achieve the above-described object, the invention according to claim 2 is a target projection optical system for projecting target light from an oblique direction to the eye to be examined, and the target projection to the eye optical axis to be examined. A corneal endothelium provided with an alignment detection optical system that is provided in a substantially symmetric direction with respect to the optical system and receives the reflected light of the target light from the corneal endothelial cell surface of the eye to be examined and detects the relative positional relationship between the device and the eye to be examined. In the cell imaging apparatus, the target projection optical system is a pair of first and second target projection optical systems provided symmetrically with respect to the optical axis of the eye to be examined, and the alignment detection optical system is the eye light to be examined. A pair of first and second alignment detection optical systems provided symmetrically with respect to an axis, and a light receiving portion of the first and second alignment detection optical systems is a two-dimensional CCD, and the two-dimensional Device and corneal endothelial cells based on CCD output Wherein the alignment detection circuit for calculating the relative position is provided with.
[0012]
The invention of claim 3 is characterized in that the light sources of the pair of target projection optical systems have different wavelengths.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a corneal endothelial cell imaging apparatus according to the present invention will be described with reference to FIGS.
[0014]
1A, a corneal endothelial cell imaging device S includes an anterior ocular segment observation optical system 10 that observes the anterior ocular segment of the eye E, and a fixation target projection optical system 20 that provides a fixation target to the eye E. (See FIG. 1 (B)), an illumination optical system 30 for irradiating slit light to the cornea C obliquely for photographing, an imaging optical system 40 for photographing an eye image relating to the cornea C, and obliquely to the cornea C The first target projection optical system 50 that projects alignment target light, receives the reflected light of the first alignment target from the corneal endothelial cell surface N of the cornea C, and receives the relative position between the device S and the corneal endothelial cell surface N. The first alignment detection optical system 60, the first target projection optical system 50, and the second target projection provided in symmetrical positions with the optical axis of the eye E to be examined as the axis. Optical system 50 'and second alignment detection optical system 60' It has.
[0015]
The anterior ocular segment observation optical system 10 is positioned on the left and right sides of the eye E to be examined, and an anterior ocular segment observation light source 11 that emits a plurality of infrared lights that directly illuminate the anterior ocular segment. Is provided with a CCD camera having a dichroic mirror 12, an objective lens 13, and a two-dimensional CCD 14, and O1 is an optical axis thereof.
[0016]
The image of the anterior segment of the eye E illuminated by the anterior segment illumination light source 11 passes through the dichroic mirror 12 and is then focused by the objective lens 13 and formed on the two-dimensional CCD 14. The two-dimensional CCD 14 outputs an image signal to a monitor device (not shown) and displays an anterior ocular segment image on the screen 15 of the monitor device (not shown).
[0017]
The fixation target projection optical system 20 includes a fixation target light source 21 that emits visible light, a pinhole plate 22, a projection lens 23, and a dichroic mirror 12, as shown in FIG.
[0018]
The fixation target light emitted from the fixation target light source 21 is converted into a parallel light beam by the projection lens 23 through the pinhole plate 22 and then reflected by the dichroic mirror 12. The subject's line of sight is fixed by gazing at the fixation target light reflected by the dichroic mirror 12 as a fixation target.
[0019]
The illumination optical system 30 includes a photographing illumination light source 31 using a xenon lamp, a condenser lens 32, a slit plate 33, an aperture stop 34, a dichroic mirror 35 that transmits visible light and reflects infrared light, and an objective lens 36. O2 is the optical axis.
[0020]
Visible light emitted from the illuminating light source 31 for photographing at the time of photographing is condensed by the condenser lens 32, guided to the slit plate 33, passes through the aperture stop 34, passes through the dichroic mirror 35, and is cornea C by the objective lens 36. And illuminates so as to cross from the corneal surface T toward the inside.
[0021]
FIG. 2A shows how the slit light beam L projected by the illumination optical system 30 is reflected by the cornea C. FIG. A part of the slit light beam L is first reflected on the corneal surface T, which is the interface between the air and the cornea C. A part of the light beam transmitted through the corneal surface T is reflected by the corneal endothelium, that is, the corneal endothelial cell surface N. The amount of reflected light beam T ′ from the corneal surface T is the largest, the amount of reflected light beam N ′ from the corneal endothelial cell surface N is relatively small, and the amount of reflected light beam M ′ from the corneal substance M is the smallest.
[0022]
The photographing optical system 40 is disposed at a position that does not interfere with the objective lens 41, a dichroic mirror 42 that transmits visible light and reflects infrared light, a mask 43, a mirror 44, a relay lens 45, and an anterior ocular segment observation light beam. The mirror 46 and the two-dimensional CCD 14 are tilted at the same angle as the tilt angle θ on the object side (the eye E side), and O3 is the optical axis.
[0023]
The visible light reflected light beam irradiated by the illumination optical system 30 and reflected by the cornea C passes through the dichroic mirror 42 while being condensed by the objective lens 41 and forms an image on the mask 43. Further, the mask 43 blocks an extra reflected light beam other than that for forming a corneal endothelial cell image, and the reflected light beam that has passed through the mask 43 is reflected by the mirror 44, reflected by the mirror 46 while being focused by the relay lens 45, and the CCD camera. A corneal endothelial cell image is formed on 14. The two-dimensional CCD 14 outputs an image signal to the monitor device, and a corneal endothelial cell image 47 is displayed on the screen 15 of the monitor device (not shown) as shown in FIG. In FIG. 2B, 48 indicated by a broken line is an optical image formed by a reflected light beam T ′ from the corneal surface T if it is not shielded by the mask 43 of FIG. 2B is a portion shielded by the mask 43. In FIG.
[0024]
The first index projection optical system 50 includes a light source 51 that emits infrared light, a pinhole plate 52, an aperture stop 53, a half mirror 54, a dichroic mirror 35, and an objective lens 36, and O2 is the optical axis thereof. .
[0025]
The infrared light emitted from the light source 51 passes through the pinhole plate 52, passes through the aperture stop 53, is reflected by the half mirror 54, is reflected by the dichroic mirror 35, is focused by the objective lens 36, and is guided to the cornea C. It is burned.
[0026]
FIG. 3A shows how the index light beam F projected by the first index projection optical system 50 is reflected by the cornea C. FIG. Part of the index light beam F is first reflected on the cornea T, which is the interface between the air and the cornea C. A part of the light beam transmitted through the corneal surface T is reflected by the corneal endothelial cell surface N. The amount of reflected light beam T ″ from the corneal surface T is the largest, the amount of reflected light beam N ″ from the corneal endothelial cell surface N is relatively small, and the amount of reflected light beam M ″ from the corneal substance M is the smallest.
[0027]
The first alignment detection optical system 60 includes an objective lens 41, a dichroic mirror 42, a half mirror 54 ', a CCD camera having a two-dimensional CCD 61, and an alignment detection circuit 62, and O3 is an optical axis thereof.
[0028]
Reflected light from the cornea C of the index light projected by the first index projection optical system 50 is reflected by the dichroic mirror 42 while being focused by the objective lens 41, passes through the half mirror 54 ′, and is coupled onto the two-dimensional CCD 61. Imaged. An image as shown in FIG. 3B is formed on the two-dimensional CCD 61. In FIG. 3B, 63 is an optical image of the light beam reflected by the corneal surface T, and 64 is an optical image of the light beam reflected by the corneal endothelial cell surface N. Of these, the alignment detection circuit 62 detects 64 positions having information on the corneal endothelial cell surface N (corneal endothelium), and based on this, detects the position of the corneal endothelial cell surface N.
[0029]
The second index projection optical system 50 'includes a light source 51' that emits infrared light, a pinhole plate 52 ', an aperture stop 53', a half mirror 54 ', a dichroic mirror 42, and an objective lens 41. The optical axis.
[0030]
The second alignment detection optical system 60 ′ includes an objective lens 36, a dichroic mirror 35, a half mirror 54, a two-dimensional CCD 61 ′, and an alignment detection circuit 62, where O 2 is the optical axis.
[0031]
Similarly to the first index projection optical system 50 and the first alignment detection optical system 60, the second index projection optical system 50 ′ and the second alignment detection optical system 60 ′ detect the position of the corneal endothelial cell surface N. The output of the two-dimensional CCD 61 ′ is guided to the alignment detection circuit 62.
[0032]
At this time, the light sources 51 and 51 ′ are blinked, and the blinking phases of the light sources 51 and 51 ′ are shifted by a half cycle, and the detection of the reflected light by the cornea C is also synchronized with each. Thereby, the reflected light of the index light by the first index projection optical system 50 affects the output of the second alignment detection optical system 60 ', and conversely, the index by the second index projection optical system 50'. The reflected light does not affect the output of the first alignment detection optical system 60.
[0033]
4A to 4D show the reflected light and the state of the optical image on the corneal endothelial cell surface N on the two-dimensional CCDs 61 and 61 ', and the optical image of the reflected light from the corneal surface T is omitted. It is. 4, f is illumination light from the light source 51 in FIG. 1, f ′ is illumination light from the light source 51 ′ in FIG. 1, 64 is an image of the pinhole 52 formed in the two-dimensional CCD 61 by the illumination light f, 64 'Indicates an image of the pinhole 52' formed in the two-dimensional CCD 61 'by the illumination light f'. From the positions of the images 64 and 64 ′, it can be seen whether or not the alignment of the device S and the corneal endothelial cell surface N is aligned as shown in FIGS.
[0034]
That is, FIG. 4A shows a state where the apparatus S and the corneal endothelial cell surface N are aligned because the images 64 and 64 ′ are located at the center of the two-dimensional CCDs 61 and 61 ′. . 4B, since the images 64 and 64 ′ are shifted in the left-right direction from the center of the two-dimensional CCD 61, 61 ′, the device S is shifted in the left-right direction with respect to the corneal endothelial cell surface N. Indicates the state. Further, FIG. 4C shows a state in which the device S is shifted in the vertical direction with respect to the corneal endothelial cell surface N because the images 64 and 64 ′ are shifted upward from the center of the two-dimensional CCD 61 and 61. ing. 4D shows that the images 64 and 64 ′ are displaced in the left-right direction and in the opposite directions with respect to the center of the two-dimensional CCD 61, 61, so that the apparatus S is in the front-rear direction with respect to the corneal endothelial cell surface N. It represents a state that is shifted to.
[0035]
The alignment detection circuit 62 calculates the relative positional relationship between the device S and the corneal endothelial cell surface N based on the outputs of the two-dimensional CCDs 61 and 61 ′ and outputs the calculated relative positional relationship to the control circuit 70. The control circuit 70 generates information representing the relative positional relationship between the device S and the corneal endothelial cell surface N by image generation means (not shown) and displays the information on the monitor screen 15. Further, when the output of the alignment detection circuit 62 falls within a predetermined range, the control circuit 70 turns off the light sources 11, 51, 51 ′ and causes the imaging light source 31 to emit light to take a corneal endothelial cell image.
[0036]
The examiner moves the device S based on the positional information provided from the device while observing the anterior segment image of the eye E on the monitor screen, and the positional relationship between the device S and the eye E falls within a predetermined range. A corneal endothelial cell image is taken.
[0037]
By the way, in the said Example, although two light-receiving parts were provided for alignment detection, you may comprise so that one light-receiving part may be shared. In addition, the light of the two alignment detection systems is separated by shifting the blinking phases of the light sources 51 and 51 ', but the present invention is not necessarily limited to this. For example, the wavelengths of light emitted from the light sources 51 and 51 ′ are made different, and the dichroic mirrors 35 and 42 are configured to reflect light from the light sources 51 and 51 ′ and transmit light of other wavelengths, respectively. May be.
[0038]
Furthermore, by providing a driving means in the apparatus, the apparatus may be automatically moved based on the output of the alignment detection means to take a corneal endothelial cell image.
[0039]
【The invention's effect】
As described above, the invention of claim 1 includes a target projecting optical system for projecting a target light from an oblique direction with respect to the eye, the visual target projection optical system and substantially to the subject's eye optical axis the reflected light from the cornea endothelium surface of the provided symmetrically direction and the target light is received by the two-dimensional CCD, corneal endothelium comprising an alignment detection optical system for detecting a relative positional relationship between the device and the eye to be examined In the cell imaging apparatus, the target projection optical system is a pair of first and second target projection optical systems provided symmetrically with respect to the optical axis of the eye to be examined, and the alignment detection optical system is the eye light to be examined. A pair of first and second alignment detection optical systems provided symmetrically with respect to the axis, and the device and the corneal endothelial cell surface based on the output of the two-dimensional CCD of the first and second alignment detection optical systems Alignment test that calculates the relative position of Since the configuration circuit is provided, since that can be made to the alignment detection even corneal endothelium i.e. corneal endothelial cells surfaces of vertical and horizontal direction with the longitudinal direction, and reduce the burden of the examiner, shooting mistakes Reduction can be achieved.
[0040]
According to a second aspect of the present invention, there is provided a target projection optical system for projecting target light from an oblique direction to the eye to be examined, and a direction substantially symmetrical to the target projection optical system with respect to the eye optical axis to be examined. In the corneal endothelial cell imaging apparatus provided with an alignment detection optical system that is provided and receives reflected light from the surface of the eye corneal endothelial cell of the eye to be examined and detects a relative positional relationship between the apparatus and the eye to be examined. The projection optical system is a pair of first and second target projection optical systems provided symmetrically with respect to the optical axis of the eye to be examined , and the alignment detection optical system is provided symmetrically with respect to the optical axis of the eye to be examined . A pair of first and second alignment detection optical systems, and a light receiving portion of the first and second alignment detection optical systems is one two-dimensional CCD, and an apparatus based on the output of the two-dimensional CCD An array that calculates the relative position to the corneal endothelial cell surface Since a configuration that placement detecting circuit is provided, in addition to the effect of the invention of claim 1, the number of parts can be reduced.
[0042]
Moreover, in the invention of claim 3, since the light sources of the pair of target projection optical systems have different wavelengths, the alignment light from the light source of one of the alignment optical systems is reflected on the surfaces of the plurality of optical components of the apparatus. Thus, it is possible to prevent the alignment detection of the other alignment optical system from being affected. As a result, more accurate alignment can be performed.
[Brief description of the drawings]
1A is an explanatory diagram showing an optical system of a corneal endothelial cell imaging apparatus according to the present invention, and FIG. 1B is an explanatory diagram of a fixation target projection optical system of the corneal endothelial cell imaging apparatus.
2A is an explanatory diagram showing the relationship between the slit illumination light beam projected on the cornea of the eye to be examined and the reflection; FIG. 2B is a photograph taken by the optical system shown in FIG. 1A and displayed on a monitor television; It is explanatory drawing of the obtained corneal endothelial cell image.
3A is an explanatory diagram showing the relationship between an alignment light beam (spot light beam) projected on the cornea of the eye to be examined and its reflected light beam, and FIG. 3B is a reflected light beam from the cornea surface and corneal endothelium in FIG. It is explanatory drawing of the alignment light beam image by.
4A is an explanatory diagram of an alignment light beam in a state in which the apparatus is aligned with the corneal endothelium of an eye to be examined, and FIG. 4B1 is a state in which the apparatus is shifted in the left-right direction with respect to the corneal endothelium. An explanatory view of the alignment light beam, (C1) is an explanatory view of the alignment light beam in a state in which the device is vertically displaced with respect to the corneal endothelium, and (D1) is a state in which the device is displaced in the front-rear direction with respect to the corneal endothelium. It is explanatory drawing of the alignment light beam. (A) to (D) are images of alignment light flux images respectively formed on the pair of area CCDs for alignment detection shown in FIG. 1 by reflected light from the corneal endothelium in (A1) to (D1). It is explanatory drawing.
[Explanation of symbols]
E ... Eye 50 ... First target projection optical system 50 '... Second target projection optical system 51, 51' ... Light source 60 ... First alignment optical system 60 '... Second alignment optical system 61, 61 '... two-dimensional CCD

Claims (3)

A target projection optical system for projecting a target light from an oblique direction with respect to the eye, the said visual target projection optical system and disposed substantially symmetrical direction and the target light to the subject's eye optical axis In a corneal endothelial cell imaging apparatus including an alignment detection optical system that receives reflected light from the optometric corneal endothelial cell surface with a two-dimensional CCD and detects the relative positional relationship between the apparatus and the eye to be examined .
The target projection optical system is a pair of first and second target projection optical systems provided symmetrically with respect to the eye optical axis to be examined, and the alignment detection optical system is symmetrical with respect to the eye optical axis to be examined. A pair of first and second alignment detection optical systems, and a relative position between the device and the corneal endothelial cell surface based on the output of the two-dimensional CCD of the first and second alignment detection optical systems. A corneal endothelial cell imaging apparatus, comprising an alignment detection circuit for calculation . A target projection optical system for projecting target light from an oblique direction to the eye to be examined; and a target projection light system provided in a direction substantially symmetrical to the target projection optical system with respect to the eye optical axis to be examined. In a corneal endothelial cell imaging device including an alignment detection optical system that receives reflected light from the optometric corneal endothelial cell surface and detects the relative positional relationship between the device and the eye to be examined.
The target projection optical system is a pair of first and second target projection optical systems provided symmetrically with respect to the eye optical axis to be examined, and the alignment detection optical system is symmetrical with respect to the eye optical axis to be examined. A pair of first and second alignment detection optical systems provided, and a light receiving portion of the first and second alignment detection optical systems is a single two-dimensional CCD, based on the output of the two-dimensional CCD. A corneal endothelial cell imaging device, wherein an alignment detection circuit for calculating a relative position between the device and the corneal endothelial cell surface is provided . The corneal endothelial cell imaging apparatus according to claim 1, wherein the light sources of the pair of target projection optical systems have different wavelengths.

Images