JP2009291516A - Ophthalmologic examination apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ophthalmologic examination apparatus examining an optionally selected region of the anterior segment of an examined eye without necessarily shifting the line of sight of the examined eye to the periphery. <P>SOLUTION: The ophthalmologic examination apparatus includes an illumination optical system 11 and an imaging optical system 12 for examining the examined eye, and an optical reference axis positioning mechanism. The optical reference axis positioning mechanism matches the direction of an optical reference axis, which divides the angle between the optical axis of the illumination optical system 11 and the optical axis of the imaging optical system 12 crossing each other into two sections, to a normal line at an optionally selected position on the surface of the cornea of the examined eye at least by inclining the optical reference axis or by linearly moving the optical reference axis. The optical reference axis positioning mechanism includes a first mechanism for inclining the optical reference axis within one surface, a second mechanism for inclining the axis within a surface perpendicular to the one surface, and a third mechanism 2 for advancing/retreating the axis in three axial directions including the direction toward the examined eye, which make right angles between one another. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an ophthalmic examination apparatus. More specifically, the present invention relates to an ophthalmic examination apparatus including a corneal endothelial cell photographing apparatus for observing and photographing corneal cells by a specular method, for example. Here, the specular type imaging apparatus irradiates illumination light obliquely with respect to the optical axis of the eye to be examined, receives specular reflection light from the cornea obliquely, and observes and photographs this image.

  In a conventional corneal endothelial cell imaging apparatus, an order is given to a subject to fixate a fixation lamp, and a desired part of the eye to be fixed is imaged by fixing the fixation lamp. As such a corneal endothelial cell imaging apparatus, those disclosed in Patent Document 1 and Patent Document 2 are known. In this corneal endothelial cell imaging apparatus, fixation lamps are installed at a plurality of selected locations. An observation site on the eye to be examined is selected by causing the subject to appropriately fixate the designated fixation lamp, and the site is imaged toward the front of the apparatus.

Thus, since the installation positions of the plurality of fixation lamps are fixed, it is possible to image only a predetermined limited portion of the surface of the eye to be examined. That is, an arbitrarily selected part cannot be imaged. Moreover, since the installation range of the plurality of fixation lamps in the apparatus is limited, the imaging range of the eye to be examined is limited accordingly. Furthermore, it is necessary for the subject to fixate his / her eyes by moving his / her line of sight to a different fixation lamp each time an image is taken. There are also subjects who have difficulty in moving their eyes to a fixation lamp that is far away.
Japanese Patent Application Laid-Open No. 07-088086 Japanese Patent Application Laid-Open No. 07-100111

  The present invention has been made to solve such a problem, and even when examining a plurality of different parts, it is not necessary to change the line-of-sight direction while the eye is fixed, and any part of the surface of the eye to be examined can be obtained. An object of the present invention is to provide an ophthalmic examination apparatus which can be examined by observing, photographing, etc. from the normal direction.

The ophthalmic examination apparatus of the present invention is
An ophthalmic examination apparatus for examining an arbitrary position in an anterior segment of an eye to be examined,
Inspection optical system for eye examination;
An optical reference axis positioning mechanism that aligns the direction of the optical reference axis with the normal of the arbitrary position on the corneal surface of the eye to be examined by tilting at least one of the tilt and linear movement of the optical reference axis of the inspection optical system. ing.

  Due to such a configuration, the ophthalmic examination apparatus of the present invention can align the optical reference axis of the examination optical system with a normal at an arbitrary position on the corneal surface of the eye to be examined. Therefore, it is not necessary for the eye to be examined to shift the line of sight especially to change the imaging region. Moreover, since the optical reference axis can reach any position on the corneal surface, the examination site is not limited. The optical reference axis can be tilted by, for example, bending the optical axis using a reflecting member or the like, or tilting the optical system itself.

  In this ophthalmic examination apparatus, an anterior ocular segment observation optical system having a camera for imaging the anterior ocular segment of the eye to be examined, and a test area is designated on the anterior ocular segment image captured by the anterior ocular segment observation optical system And a normal direction calculation for calculating the normal direction of the position specified by the position specifying means based on the relative positional relationship between the corneal vertex position on the anterior segment image and the specified position Means.

  Alternatively, using a predetermined radius of curvature of the cornea of the human eye, a plurality of predetermined points on the anterior segment image of the human eye determined in advance and the direction of the normal on the cornea at the predetermined point are calculated. The normal direction can be determined in such a manner that the normal direction at the designated position is determined by saving the normal data and selecting and designating the predetermined point. According to such a configuration, the normal direction at the test site of the eye to be examined can be determined without using the actual eye to be examined, so that the examination itself is quick and easy.

  Then, an illumination optical system for illuminating the anterior eye portion of the eye to be examined from the oblique front by illumination light to the inspection optical system, and imaging for receiving reflected light reflected by the anterior eye portion of the illumination light An optical system, and an axis in a direction that bisects the intersection angle between the illumination optical axis of the illumination optical system and the imaging optical axis of the imaging optical system can be set as the optical reference axis. Thus, the ophthalmic examination apparatus of the present invention can be configured as a specular ophthalmic imaging apparatus.

  The optical reference axis positioning mechanism includes a first mechanism for tilting the optical reference axis in one plane, a second mechanism for tilting the optical reference axis in a plane perpendicular to the one plane, and a direction toward the eye to be examined. A third mechanism that moves forward and backward in each of the three axial directions forming a right angle can be provided. For example, a known XYZ table may be used as the third mechanism.

Along with the anterior ocular segment observation optical system having a camera for photographing the anterior ocular segment of the eye to be examined, and the observation optical axis of the anterior ocular segment observation optical system. An alignment index projection optical system for irradiating the eye to be examined with alignment index light,
The anterior ocular segment observation optical system is configured so that the corneal apex position of the anterior ocular segment can be detected by the camera receiving a reflected image of the alignment index light from the surface of the eye to be examined.
The third mechanism can be configured to align the inspection optical system with respect to the eye to be examined by moving the reflected image so as to fall within a predetermined range of the imaging screen of the camera.

The ophthalmic examination apparatus further includes a position fixing unit that fixes the eye to be examined at a predetermined position,
The first mechanism is configured to tilt the inspection optical system with a point set so as to substantially correspond to the center point of the anterior segment spherical surface of the eye to be examined in the position fixing unit,
The second mechanism can be provided with a tiltable reflecting member for reflecting the optical reference axis to bend its direction.

The ophthalmic examination apparatus further includes a position fixing unit that fixes the eye to be examined at a predetermined position,
The first mechanism is configured to tilt the inspection optical system with a point set so as to substantially correspond to the center point of the anterior segment spherical surface of the eye to be examined in the position fixing unit,
The second optical mechanism can be configured to tilt the inspection optical system with a point set so as to substantially correspond to the center point of the anterior spherical surface of the eye to be examined in the position fixing unit. .

A fixation target for maintaining the orientation of the subject eye in a single direction by fixing the subject eye to the subject eye is provided in a fixed and immovable state, and the reflecting member reflects a part of the light and transmits a part thereof. Composed of a translucent mirror member,
Since the fixation target is disposed behind the translucent mirror member when viewed from the eye to be inspected at the position fixing portion, the fixation eye passes through the translucent mirror member and fixes the fixation target. It can be configured to be visible.

  The anterior ocular segment observation optical system is provided in an immovable fixed state, and the anterior ocular segment observation optical system is disposed behind the translucent mirror member when viewed from the eye to be examined in the position fixing unit, and is translucent. Between the mirror member and the eye to be examined at the position fixing unit, the optical axis of the anterior ocular segment observation optical system can be configured to follow the axis from the eye to the fixation target.

  According to the ophthalmic examination apparatus of the present invention, since the optical reference axis of the examination optical system is aligned with the normal of the arbitrary position on the corneal surface of the eye to be examined, the eye to be examined has a line of sight especially in order to change the imaging region. There is no need to move it. Moreover, since the optical reference axis can reach an arbitrary position on the corneal surface, the examination site is not limited.

  Embodiments of the ophthalmic examination apparatus of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view showing the external appearance of a corneal endothelial cell imaging apparatus which is an embodiment of the ophthalmic examination apparatus of the present invention. FIG. 2 is a perspective side view showing an optical system inside the corneal endothelial cell imaging apparatus of FIG. FIG. 3 is an optical path diagram showing an optical system arranged in the main body 3 of the corneal endothelial cell imaging apparatus of FIG. 4 (a) and 4 (b) are schematic plan views showing horizontal movement of the corneal endothelial cell imaging apparatus of FIG.

  The corneal endothelial cell imaging apparatus 1 shown in FIGS. 1 to 4 imposes troubles such as moving the line of sight of the corneal endothelial cells in any part of the anterior eye portion of the subject's eye without any positional restriction. It is a device that has been devised for shooting without any problems.

  This corneal endothelial cell imaging device (hereinafter also simply referred to as “device”) 1 has a main body 3 mounted on an XYZ frame (also referred to as a triaxial frame) 2 as a third mechanism. The XYZ frame 2 includes an X table 4 installed on the base 2a so as to be slidable in the left-right direction (X-axis direction), and a Z table 6 installed on the X table 4 so as to be slidable in the front-rear direction (Z-axis direction). The Y table 5 is installed on the Z table 6 so as to be movable up and down in the vertical direction (Y-axis direction). In the present embodiment, the Y table 5 is attached so as to be movable up and down along a stand box 7 erected on the rear side of the Z table 6. Here, the eye E side viewed from the apparatus 1 is referred to as the front, and the opposite side is referred to as the rear.

  The main body 3 is installed on the upper surface of the Y table 5 so as to be able to turn (revolve) in an angular range of 52 ° around a vertical axis (Y axis). Specifically, it is installed so that it can be turned (revolved) by 26 ° around the predetermined point C (see FIG. 4) on the unitary body of the Y table 5 and the main body 3 and horizontally on the horizontal plane with the Z axis as the center. Has been. As an example of the first mechanism for turning in this way, a guide rail 8 is formed on the lower surface of the main body 3, an arc-shaped rack (not shown) is disposed along the guide rail 8, and a pinion gear is installed. An attached servo motor (not shown) may be installed in the Y table 5. Then, the pinion gear may be assembled so as to be engaged with the arc-shaped rack after being fitted into the guide rail 8. According to this configuration, the arcuate rack can be revolved integrally with the main body 3 by rotationally driving the pinion gear by the servo motor.

  All the optical systems 11 to 15 shown in FIG. 3 are accommodated in the main body 3 of the apparatus 1 shown in FIG. The optical system in the main body 3 in FIG. 2 is a side view of the optical system in FIG. However, in FIG. 2, among the optical systems 11 to 15 in FIG. 3, the illumination optical system 11, the imaging optical system 12, and the focusing optical system 13 are shown only by reference numerals in order to avoid difficulty in viewing, and the illustration thereof is omitted. Has been. The illumination optical system 11 is an optical system for illuminating the anterior eye portion of the eye E to be examined from the oblique front thereof with illumination light, and the imaging optical system 12 reflects the reflected light reflected by the anterior eye portion of the illumination light. An optical system for receiving light. The focusing optical system 13 will be described later. The illumination optical system 11 and the photographing optical system 12 constitute an inspection optical system.

  As apparent from FIG. 3, the optical axis (also referred to as illumination optical axis) 11a of the illumination optical system 11 and the optical axis (also referred to as imaging optical axis) 12a of the photographing optical system 12 naturally intersect. . A straight line that bisects the angle formed by the illumination optical axis 11a and the photographing optical axis 12a is used as the optical reference axis S of the inspection optical system. Further, the intersection of the illumination optical axis 11a and the imaging optical axis 12a is located behind the predetermined point C by a general radius of curvature R of the cornea of the eye to be examined.

  The main body 3 further includes a focusing optical system 13 for making the focal point F (intersection of the illumination optical axis 11a and the imaging optical axis 12a) F of the imaging optical system 12 coincide with the corneal endothelium that is the imaging site, An anterior ocular segment observation optical system 14 having a television camera 21 for observing the anterior ocular segment of the optometry E, and the alignment index light is irradiated to the eye E along the observation optical axis 14a of the anterior ocular segment observation optical system 14 The alignment index projection optical system 15 is accommodated. The anterior ocular segment observation optical system 14 is configured to be able to detect the corneal apex position of the anterior ocular segment when the television camera 21 receives a reflection image of the alignment index light from the surface of the eye to be examined. The main body 3 is formed with a window 3a through which the optical axis reaching the eye to be examined of each of the optical systems 11 to 15 passes. In addition, a fixation lamp 9 is installed inside the stand box 7 to keep the eye E in a single direction by fixing the eye E (see FIG. 4A). See also).

  Further, in front of the main body 3, a forehead pad 10A on which the subject presses the forehead and an elevating chin rest 10B for placing the chin are installed. The face of the subject is fixed to the main body 3 with the forehead 10A and the liftable chin rest 10B. Then, the height of the eye E is matched with the height position of the fixation lamp 9 by raising and lowering the elevating jaw table 10B. Further, as shown in FIG. 4B, the fixation lamp 9 is adjusted to be positioned in the line-of-sight direction of the eye E by moving the X table 4 in the left-right direction (X-axis direction).

  FIG. 3 shows these optical systems 11 to 15 in detail. First, the illumination optical system 11 has a strobe discharge tube 16 as a light source for anterior segment illumination. Visible light from the strobe discharge tube 16 passes through the condenser lens 17 and is focused on the slit 18, and this slit light is converged on the cornea of the eye E by the illumination lens 19. The translucent mirror 38 as the second mechanism disposed in front of the eye E will be described later. In the present embodiment, a cold mirror 20 is interposed in the middle of the optical path in order to match the optical path of the focusing optical system 13 (described later) with the optical path of the illumination optical system 11. The cold mirror 20 transmits illumination light, which is visible light, and reflects focus detection light, which will be described later, which is infrared light.

  The photographing optical system 12 has a television camera 21 for photographing corneal endothelial cells. The television camera 21 is shared by the anterior ocular segment observation optical system 14 described above. The slit light reflected by the cornea of the eye E is transmitted through the photographing lens 22, converged on the slit 23, passes through the imaging lens 24, and is received by the television camera 21. In the present embodiment, the optical path of the photographing optical system 12 is made the same as the optical path of the focusing optical system 13 to be described later halfway. For this purpose, a cold mirror 25 for branching the optical path is provided. The cold mirror 25 reflects illumination light that is visible light and transmits focus detection light that is infrared light. In this embodiment, since the television camera 21 is shared by the anterior ocular segment observation optical system 14, another cold mirror 26 is interposed to match the optical path of the anterior ocular segment observation optical system 14. .

  The alignment index projection optical system 15 includes a light emitting diode 27 as a light source for alignment index light. Near-infrared light from the light-emitting diode 27 is changed in direction by the mirror 28, converted into parallel light by the condenser lens 29, and irradiated to the anterior eye portion of the eye E from the front through the half mirror 30. A bright spot (Purkinje image), which is a reflection image of the alignment index light on the cornea of the eye E to be examined, passes through the half mirror 30, the visible light cut filter 31, and the anterior segment photographing lens 32 and is sent to the television camera 21. The television camera 21 also has an anterior segment image of the eye E illuminated by illumination light from an infrared light emitting diode 40 for anterior segment illumination fixedly disposed in front of the inspection optical systems 11 and 12. Shooting. (Deleted by one and a half lines) A Purkinje image is displayed at the apex of the cornea together with the anterior segment image on a display device (not shown). By moving the XYZ frame 2 in the XY directions so that this Purkinje image reaches a predetermined position (intersection with the optical reference axis S) in the anterior segment image, the optical reference axis S coincides with the corneal apex. This is called an alignment operation.

  Next, the focusing optical system 13 will be described. The focusing optical system 13 includes a focusing lamp 33 and a focusing light receiving element 37. The focus detection light that has passed through the condenser lens 34, the visible light cut filter 35, and the slit 36 from the focus lamp 33 reaches the eye E along the optical axis 11 a of the illumination optical system 11. The focus detection light reflected by the anterior segment of the eye E reaches the focus light receiving element 37 along the optical axis 12a of the photographing optical system 12 and is received. That is, when the intersection point F (corresponding to the in-focus point) of the optical axis 11a of the illumination optical system 11 and the optical axis 12a of the imaging optical system 12 is at the imaging region (corresponding to the corneal apex) of the eye E to be examined. The light receiving element 37 detects the reflected light of the focus detection light. Then, the focal point F is aligned with the imaging region of the eye E by moving the inspection optical systems 11 and 12 in the Z direction. This alignment is called focusing. When this focusing is performed, the predetermined point C (which coincides with a fixation height position P described later) is located at the center of curvature of the cornea of the eye E to be examined.

  As shown in FIGS. 2 and 3, a translucent mirror 38 as a second mechanism is installed in a portion of the inspection optical systems 11 and 12 that faces the eye E to be examined. The translucent mirror 38 is configured to reflect about 80 to 90% of the irradiated light and transmit about 10 to 20%. As is clear from FIG. 2, the light reflected by the translucent mirror 38 travels from the inspection optical systems 11 and 12 toward the subject eye E and from the subject eye E toward the inspection optical systems 11 and 12. On the other hand, the fixation target light from the fixation lamp 9 passes through the translucent mirror 38 and reaches the eye E to be examined. The translucent mirror 38 is attached to the main body 3 so as to be rotated (inclined) by a range of ± 13 ° around an axis in the horizontal direction (X axis), that is, up and down from the horizontal direction. As the translucent mirror 38 rotates, the optical reference axis S of the inspection optical systems 11 and 12 reflected by the translucent mirror 38 is bent within a maximum range of 52 °. As shown in FIG. 2, in detail, the optical reference axis S of the inspection optical systems 11 and 12 bent in the direction of the eye E is bent in the range of ± 26 ° up and down from the horizontal direction. Regardless of the rotation (tilt) of the translucent mirror 38, the subject looks through the translucent mirror 38 without moving the eye E to fixate the fixation lamp 9. The portion of the optical reference axis S bent on the eye E side from the translucent mirror 38 will be referred to as an optical reference axis bent portion Sb.

  In addition, the device 1 is configured such that when the translucent mirror 38 rotates (tilts) as described above, the main body 3 moves up and down by a corresponding distance in synchronization therewith. For example, when the translucent mirror 38 is tilted downward, the optical reference axis bending portion Sb is also tilted downward, but the main body 3 (including the optical systems 11 and 12) is raised by that amount. FIG. 2 shows this state. That is, the distance by which the main body 3 moves up and down is a fixation height position to be described later from the optical reference axis bending portion Sb in the translucent mirror 38 when the inclination angle of the optical reference axis bending portion Sb from the horizontal state is α °. This is a distance obtained by multiplying the distance L to P by tan α °.

  With such a configuration, the optical reference axis bending portion Sb facing the eye E direction is always a predetermined point (predetermined height position) even if it is inclined with respect to the horizontal direction. (Referred to as fixation position P). The fixation height position P coincides with the height at which the fixation lamp 9 is installed. A horizontal line from the fixation lamp 9 toward the eye E is a reference horizontal line H. The optical reference axis bent portion Sb in the standby state (reference position) is in a horizontal state and coincides with the reference horizontal line H. Both the fixation position P and the predetermined point C can be displaced in the X-axis direction and the Z-axis direction by the X table 4 and the Z table 6. Further, as shown in FIG. 2, even if the translucent mirror 38 is removed from the line of sight of the eye E reaching the fixation lamp 9 of the eye E, no part that blocks the line of sight is disposed. It does not interfere with vision.

  As described with reference to FIG. 3, the main body 3 accommodating the optical systems 11 to 15 rotates by 52 ° in the horizontal plane around the predetermined point C. Specifically, the optical system includes the main body 3 so that the optical reference axis S of the inspection optical systems 11 and 12 can always be rotated in the range of ± 26 ° to the left and right with the Z axis being centered while passing through the predetermined point C. Is placed inside. The above-described fixation height position P coincides with the predetermined point C in plan view. The angle values shown above are examples and can be easily increased or decreased as necessary. In this way, the optical reference axis can be inclined in the X direction and the Y direction around a predetermined point C (P). Further, the optical reference axis S can be moved up and down, left and right, front and rear (XYZ directions) by the XYZ mount 2.

  According to the apparatus 1 configured as described above, the optical reference axis S can be displaced in any direction and any position within a predetermined range. That is, the optical reference axis S can be made to coincide with the normal line at an arbitrary point on the cornea in the anterior segment of the eye E to be fixed. Therefore, it is possible to image corneal endothelial cells at any site.

  In addition, the apparatus 1 is provided with an imaging position designation device and a normal direction calculation device (not shown). The operation will be described with reference to FIG. FIG. 5A is a front view showing the anterior segment of the eye to be examined, the corneal apex T, and the imaging region M, and FIG. 5B is a cross-sectional view taken along line VV. The imaging position designation device is a device that designates a desired part on an anterior segment image displayed on a display device (not shown) by clicking a mouse or the like, and specifies the position of the designated part in a plane coordinate or a circular coordinate. (FIG. 5A). In this case, the origin of the coordinates is, for example, the corneal apex T on the anterior segment image viewed in the direction facing the line of sight of the eye E to be examined. On the other hand, the radius of curvature of the cornea of the human eye is almost the same, and this is R. Then, from this radius of curvature R and the distance D between the corneal apex T position on the anterior segment image and the specified position (imaging site) M, the normal direction arithmetic unit geometrically specifies the cubic of the specified position M. The direction of the normal N at the original position and the designated position M is calculated (FIG. 5B). For example, if the designated position M is a point D above the corneal apex T position in the anterior segment image and the corneal curvature radius is R, the direction of the normal N is a horizontal state passing through the pupil center. This is a direction that forms an angle of arcsin (arc sine) D / R upward with respect to the optical reference axis S.

  The guide rail 8 described above and the mechanism that moves the main body 3 along the guide rail 8 and the rotatable translucent mirror 38 that tilts the optical reference axis bending portion Sb up and down include the optical reference axis bending portion Sb. It can be called an optical reference axis positioning mechanism for following a normal at an arbitrary designated position on the eye to be examined.

  Hereinafter, the operation of the apparatus 1 for photographing an arbitrary point of the cornea of the eye to be examined will be described.

  First, the subject places his / her face on the liftable chin rest 10A and the forehead rest 10B and fixes them. Next, it is determined whether the inspection target is the right eye or the left eye, and the main body 3 is moved by sliding the X table 4 so that the fixation lamp 9 faces the determined inspection target eye (for example, the left eye) E ( FIG. 4 (b)). At the same time, the elevating chin rest 10 </ b> A is moved up and down so that the height position of the eye E is substantially matched with the fixation lamp 9. Then, the subject is caused to fixate the fixation lamp 9 (FIGS. 2 and 4B). At this time, the optical reference axis bending portion Sb coincides with the reference horizontal line H of the fixation lamp 9. Further, the main body 3 is at a rear standby position that is farthest from the eye E to be examined. When the operation of the optical system starts in this state, the anterior segment image can be observed through the display device because the television camera 21 of the anterior segment observation optical system 14 photographs the anterior segment.

  When the above-mentioned stand box 7 is not erected on the Z table 6 but is erected on the base 2a that does not move, the two right and left fixation lamps 9 at the same height in the stand box 7 are used. Can be installed. And what is necessary is just to set the separation distance of the both fixation lamps 9 to about 60-80 mm which is the same as a general human eye interval. Moreover, you may comprise so that a separation distance can be adjusted in this range as needed. With this configuration, it is only necessary to turn on the fixation lamp 9 that faces the determined eye (for example, the left eye) E among the two fixation lamps 9 (FIG. 4).

  Then, the alignment reference projection optical system 15 and the anterior ocular segment observation optical system 14 make the optical reference axis bent portion Sb coincide with the corneal apex of the eye E to be examined. Specifically, the XYZ mount 2 is advanced toward the eye E (Z direction). Then, when the Purkinje image can be detected by the anterior ocular segment observation optical system 14, the XYZ frame 2 is displaced in the X direction and the Y direction to perform alignment and focusing on the center of the pupil. In a state where alignment is performed, an imaging region M (FIG. 5A) is designated by clicking the mouse on the anterior segment image in the display device. Then, the coordinates of the designated position are specified by the photographing position designation device, and the designated position (photographing point) M and the direction of the normal N there are computed by the normal direction computing device. Alternatively, when the imaging region M is designated on the anterior segment image, it may be recognized which of the divided areas prepared by the mouse corresponds in advance, and the representative position of the area may be used as the designated position.

  Next, by tilting the translucent mirror 38 by a predetermined angle from the horizontal state, the optical reference axis bent portion Sb is tilted by the vertical (Y direction) angle of the calculated normal, and at the same time along the guide rail 8. By turning the main body 3, the optical reference axis bent portion Sb is inclined by the horizontal (X direction) angle of the calculated normal N. Thereby, the optical reference axis bent portion Sb is made parallel to the calculated normal line N. At this time, the position of the Purkinje image (corneal apex) on the image in the vicinity of the designated position M photographed by the television camera 21 exactly matches the designated position M. This is because the optical reference axis bent portion Sb is parallel to the normal line N at the designated position M. Therefore, the anterior segment image displayed on the display device is not an image of the subject eye E viewed from the front but an image viewed in the normal N direction at the designated position M.

  After that, alignment and focusing similar to those of the conventional corneal endothelial cell imaging apparatus are automatically performed while the optical reference axis bending portion Sb is in a state parallel to the normal line N. That is, the operation of the anterior ocular segment observation optical system 14, the alignment index projection optical system 15, and the focusing optical system 13 moves the XYZ mount 2 in the three-axis directions, and moves the focal point F of the inspection optical system to the designated position M. The main body 3 is moved so as to substantially coincide with. When this alignment and focusing are performed, the stroboscopic discharge tube 16 of the illumination optical system 11 emits light and the corneal endothelial cell at the specified position M is photographed.

  In the embodiment described above, the imaging point M is directly specified on the anterior segment image of the eye E, but the present invention is not limited to this method. For example, an anterior segment image of a standard-sized dummy eye having the above-described general corneal curvature radius R is stored in the apparatus 1 and the dummy anterior segment image is displayed to display the photographing point M. May be specified. Even when the dummy anterior eye part image is used, the subject is caused to fixate the fixation lamp 9 and the optical reference axis bending part Sb is directed to the eye E as in the case where the real eye is used. However, since the actual eye to be examined is not required for the purpose of designating the imaging region, the anterior ocular segment observation optical system 14 is not required.

  Simultaneously with or after the above operation, a dummy anterior ocular segment image is displayed on the display device, and the imaging region M is designated by clicking with the mouse. Then, the coordinates of the designated position (for example, XY coordinates and circle coordinates on the anterior segment image) are specified by the imaging position designation device, and the designated position (imaging point) M and the normal N at the specified position (imaging point) by the normal direction calculation device. Is calculated. Of course, instead of calculating the normal N direction by the normal direction calculation device every time a photographing point is designated, the coordinates of all points on the dummy anterior eye image and the direction of the normal corresponding to this are previously stored. May be stored in the apparatus 1 as data, and these may be selected.

  Further, instead of these operations, a coordinate value may be directly input using a numeric keypad or the like. Then, as described above, the normal directions corresponding to these coordinate values may be stored in the apparatus 1 as data, and these may be selected.

  Next, by tilting the translucent mirror 38 by a predetermined angle from the horizontal state, the optical reference axis bent portion Sb is tilted by the vertical (Y direction) angle of the calculated normal, and at the same time, the guide rail of the main body 3 The optical reference axis bending part Sb is inclined by the horizontal direction (X direction) angle of the calculated normal line by the turning along 8. Thereby, the optical reference axis bent portion Sb is made parallel to the calculated normal line N.

  Then, the vicinity of the designated position M of the actual eye E is photographed by the television camera 21, and the photographed image is displayed on the display device. Since the position (corneal apex) of the Purkinje image on this image substantially coincides with the designated position M, thereafter, the anterior ocular segment observation optical system 14, the alignment index projection optical system 15, and the focusing optical system 13 are used. By the above operation, the main body 3 is moved so that the focal point F of the inspection optical system substantially coincides with the designated position M while moving the XYZ frame 2 in the three axis directions. That is, alignment and focusing are performed. When this alignment and focusing are performed, the stroboscopic discharge tube 16 of the illumination optical system 11 emits light and the corneal endothelial cell at the specified position M is photographed.

  As described above, according to this apparatus 1, an arbitrary point on the cornea can be imaged without having to fixate a fixation lamp at a different position for each imaging.

  FIGS. 6 and 7 show a corneal endothelial cell imaging device 41 that exhibits a similar function with a configuration different from the embodiment described above. In this apparatus 41, a part of all the optical systems 11 to 15 is disposed in the main body 3, and the other part is disposed in the stand box 7. That is, a part of the entire optical system can rotate about the X axis and turn (revolve) about the Y axis along with the movement in the three axis directions, but other parts including the fixation lamp 9 together with the stand box 7 Only XZ biaxial movement is possible. Thus, by dividing the optical system into two, it is possible to reduce the optical system that has to be disposed in an inclined manner in the main body 3, and to make the main body 3 that needs to be rotated as small and light as possible.

  As shown in FIG. 6, in this embodiment, the illumination optical system 11, the photographing optical system 12, and the focusing optical system 13 (the above are shown in FIG. 7) are arranged in the main body 3, and the anterior ocular segment observation optical The system 42, the alignment index projection optical system 43, and the fixation lamp 9 are disposed in the stand box 7. Note that the optical systems 11, 12, and 13 in the main body 3 in FIG. 6 are shown only by reference numerals and are not shown, but are completely the same as the optical system shown in FIG. Although the arrangement is different as described above, the illumination optical system 11, the photographing optical system 12, the focusing optical system 13, and the fixation lamp 9 itself are substantially the same as the apparatus 1 shown in FIGS. . And the external appearance and shape of this apparatus 41 are the same as the apparatus 1 shown in FIG.

  However, since the anterior ocular segment observation optical system 42 and the alignment index projection optical system 43 are arranged separately from the photographing optical system 12, the TV camera 21 shared in the above-described embodiment (FIGS. 2 and 3) is used. The television camera 21A dedicated to the anterior ocular segment observation optical system 42 is separately provided (refer to the inside of the stand box in FIG. 6), and is different from the device 1 described above. Since it is substantially the same as that shown in FIG. 2 and FIG. 3 except that this dedicated TV camera 21A is provided, the same reference numerals are assigned to the same devices, and descriptions thereof are omitted. Further, as shown in FIG. 6, the anterior ocular segment observation optical system 42 and the alignment index projection optical system 43 arranged in the stand box 7 are separated from the inspection optical systems 11 and 12 and the focusing optical system 13. In addition, a half mirror 39 not provided in FIGS. 2 and 3 is arranged. Further, between the light emitting diode 27 and the mirror 28 of the alignment index projection optical system 43, visible light transmission / reflection for joining the optical axis of the fixation lamp 9 reaching the eye E to the alignment index projection optical axis 43a. An infrared reflection mirror 44 is provided.

  Since the inspection optical systems 11 and 12 and the focusing optical system 13 need to be turned (tilted) up and down and left and right, they cannot be arranged in the stand box 7. Further, when the illumination optical system 11 and the photographing optical system 12 are arranged on the reflection side of the translucent mirror 38, a decrease in light amount and a decrease in resolution due to the illumination light and imaging light passing through the translucent mirror 38 are avoided. This is preferable. On the other hand, with respect to the anterior ocular segment observation optical system 14, the alignment index projection optical system 15, and the fixation lamp 9 arranged in the stand box 7, the light to be used passes through the translucent mirror 38 so that the amount of light is slightly increased. Even if a drop or the like occurs, there is no obstacle to observation of the anterior segment, alignment operation, and fixation by the subject.

  Further, even if the translucent mirror 38 is tilted or swiveled, the eye E can always fixate the fixation lamp 9 in front through it. Further, the anterior ocular segment observation optical system 14 and the alignment index projection optical system 15 can also perform an alignment operation by illumination light and target light transmitted through the translucent mirror 38.

  FIG. 8 shows the appearance of another corneal endothelial cell imaging device 45. Also in this device 45, although not shown, all the optical systems 11 to 15 are arranged in the main body 3 as in the above-described device 1 (FIGS. 1 to 3), and the fixation lamp 9 is placed in the stand box 7. It is fixed. However, in this device 45, the above-described translucent mirror is not pivotable and is fixed so as not to tilt (not shown). Instead, the main body 3 itself that accommodates all the optical systems 11 to 15 is attached to a channel-like swivel frame 46 that opens upward so that it can pivot up and down. By the vertical rotation of the main body 3, the optical reference axis bending portion Sb facing the eye E direction is tilted in the vertical direction integrally with the other optical axes. That is, the device 45 is different from the device 1 described above in that the translucent mirror is not a rotating type but a fixed type, and that the main body 3 is rotatable up and down.

  And when the main body 3 rotates up and down (inclination), it is comprised so that the main body 3 may raise / lower in synchronism with this. For example, when the translucent mirror 38 is tilted upward, the main body 3 (including the optical systems 11 and 12) is lowered accordingly. With this configuration, the optical reference axis bending portion Sb facing the eye E direction is always in advance with respect to the device 45 even if the optical reference axis bending portion Sb is inclined from the horizontal direction by the rotation of the main body 3. It passes through the fixation height position P determined as described above. Further, even if the translucent mirror 38 is removed from the line of sight of the body 3 that moves up and down to the fixation lamp 9 of the eye E, no part that blocks the line of sight is disposed, so that the fixation is not hindered. .

  The lower end of the channel-like swivel frame 46 is slidably engaged with a guide rail 8 as a first mechanism formed in an arc shape on the upper surface of the Y table 5. With this configuration, the revolving frame 46 is integral with the main body 3 and can be revolved (revolved) in a 52 ° angular range around the vertical axis (Y axis). The arc of the guide rail 8 is centered on a predetermined point C on the integral body of the Y table 5 and the main body 3 as in the apparatus 1 described above. Further, during operation, the predetermined point C and the fixation height position P coincide with each other in plan view. Since other configurations are substantially the same as those of the above-described apparatus 1 (FIGS. 1 to 3), the same components are denoted by the same reference numerals and description thereof is omitted.

  As described above, the main body 3 of the device 45 can move in the XYZ axis directions, can rotate around the vertical axis (Y axis), and can also rotate around the horizontal axis. However, the vertical rotation of the main body may be performed after the main body 3 rotates about the center point C of the guide rail by the rotation of the revolving frame 46. In this case, the rotation about the X axis is I can't say that. However, there is no difference in the pivoting in the vertical direction. Therefore, also with this device 45, the optical reference axis bent portion Sb can be made parallel to the normal line N at the specified position M of the eye E, as in the devices 1 and 41 described above. Focusing can be performed, and corneal endothelial cells in an arbitrary part of the anterior segment of the eye E can be imaged without moving the eye E.

  FIG. 9 shows the appearance of still another corneal endothelial cell imaging device 47. In this apparatus 47, although not shown, the illumination optical system 11, the photographing optical system 12, and the focusing optical system 13 (the above are shown in FIG. 7) are the main body, as in the above-described apparatus 41 (FIGS. 6 and 7). 3, the anterior ocular segment observation optical system 42, the alignment index projection optical system 43, and the fixation lamp 9 are disposed in the stand box 7. In the stand box 7, a window 7a is formed because it is necessary to transmit the optical paths of the fixation lamp 9 and the optical systems 42 and 43 accommodated therein to the eye E through the main body. A window (not shown) is also formed on the back surface of the main body for the same purpose. In this device 47, unlike the above-described device 41 (FIGS. 6 and 7), the translucent mirror is not rotatable but fixed so as not to tilt (not shown). Instead, the main body 3 itself can be rotated up and down as follows.

  First, from the bottom of the apparatus 47, the X table 4 is installed on the base 2a so as to be slidable in the left-right direction (X-axis direction). A stand box 7 is erected on the X table 4, and a Y table 5 is attached to the stand box 7 so as to be movable up and down. An arcuate guide rail 8 (not shown) as a first mechanism is formed on the upper surface of the Y table 5, and a channel-like swivel frame 48 opened upward is slidable on the guide rail 8. It is attached to engage. With this configuration, the turning frame 48 is integrated with the main body 3 and can turn (revolve) around the vertical axis (Y axis) in an angle range of 52 °. A channel-like turning frame 49 that is also open upward is attached to the turning frame 48 so as to be turnable up and down (front and rear). A Z table 6 to which the main body 3 is fixed is installed on the rotating frame 49 so as to be slidable in the front-rear direction (Z-axis direction).

  As described above, the main body 3 of the device 47 can move in the XYZ axis directions, can rotate around the vertical axis (Y axis), and can rotate around the horizontal axis. However, the vertical rotation of the main body may be performed after the main body 3 is rotated around the center point C of the guide rail by the rotation of the revolving frame 48. In this case, the rotation about the X axis is I can't say that. However, there is no difference in the pivoting in the vertical direction. Further, the movement of the main body 3 in the front-rear direction by the Z table 6 may be performed after the main body 3 is turned around the center point C of the guide rail by the turning of the turning frame 48. It is not a movement of direction. However, there is no difference in the movement in the front-rear direction along the optical reference axis bent portion Sb. Further, the movement of the main body 3 in the front-rear direction by the Z table 6 is not actually a movement in the Z-axis direction after the Z table 6 is tilted back and forth by the vertical rotation of the rotation frame 49. However, there is no difference in the movement in the front-rear direction along the optical reference axis bent portion Sb.

  Therefore, this device 47 can also make the optical reference axis bent portion Sb parallel to the normal N at the specified position M of the eye E, as in the above-described devices 1, 41, 45. Alignment and focusing can be performed, and corneal endothelial cells in any part of the anterior eye portion of the eye E can be imaged without moving the eye E.

  In the embodiment described above, the fixation lamp 9 does not rotate or turn, but is only moved in the XYZ axial directions. However, it is not limited to such a configuration. A large number of fixation lamps may be arranged vertically and horizontally on a plane, and arbitrary fixation lamps may be lit in order. Specifically, a large number of fixation lamps are arranged in a matrix on the front surface of the main body 3, that is, on the surface facing the eye E to be examined except for the portion through which the optical reference axis bending portion Sb passes. Then, one of the front faces is turned on, and as the main body is tilted and moved linearly, the other fixation lamps are turned on and off in turn in the direction opposite to the direction of the tilt and linear movement and at the same speed. . Even with this configuration, it is possible to hold the line of sight of the eye E in a single direction by fixing the light fixation lamp to be lit.

  In the above embodiment, the corneal endothelial cell imaging apparatus has been described as an example, but application of the present invention is not limited to this apparatus. For example, the present invention can also be applied to an apparatus for inspecting a position determined in a direction perpendicular to the cornea surface, such as an optical coherence tomography (OCT) for ophthalmology.

  According to the ophthalmic examination apparatus of the present invention, since the optical reference axis of the examination optical system is aligned with the normal of the arbitrary position on the corneal surface of the eye to be examined, the eye to be examined has a line of sight especially in order to change the imaging region. There is no need to move it. That is, the arbitrary part can be examined while the eye to be examined is fixed in one direction. Therefore, it is particularly useful for examining the surface of the anterior segment and the vicinity thereof.

It is a perspective view which shows the external appearance of the corneal endothelial cell imaging device which is one Embodiment of the ophthalmic test | inspection apparatus of this invention. It is a see-through | perspective side view which also shows the optical system inside the corneal-endothelial-cells imaging device of FIG. It is an optical path figure which shows the optical system arrange | positioned in the main body of the corneal-endothelial-cells imaging device of FIG. 4 (a) and 4 (b) are schematic plan views showing horizontal movement of the corneal endothelial cell imaging apparatus of FIG. FIG. 5A is a front view showing the anterior eye portion, the corneal apex, and the imaging point of the eye to be examined, and FIG. It is a permeation | transmission side view which shows collectively the optical system inside the corneal-endothelial-cells imaging device concerning other embodiment of this invention. It is an optical path figure which shows the optical system arrange | positioned in the main body of the corneal endothelial cell imaging device of FIG. It is a perspective view which shows the external appearance of the corneal-endothelial-cells imaging device concerning further another embodiment of this invention. It is a perspective view which shows the external appearance of the corneal-endothelial-cells imaging device concerning further another embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Corneal endothelial cell imaging device 2 XYZ mount 3 Main body 4 X table 5 Y table 6 Z table 7 Stand box 8 Guide rail 9 Fixation light 10A Forehead 10B Lifting jaw table 11 Illumination optical system 12 Imaging optical system 13 Focusing optical System 14 Anterior eye observation optical system 15 Alignment index projection optical system 16 Strobe discharge tube 17 Condensing lens 18 Slit 19 Illumination lens 20 Cold mirror 21, 21A Television camera 22 Shooting lens 23 Slit 24 Imaging lens 25 Cold mirror 26 Cold mirror 27 Light Emitting Diode 28 Mirror 29 Condensing Lens 30 Half Mirror 31 Visible Light Cut Filter 32 Anterior Eye Shooting Lens 33 Focusing Lamp 34 Condensing Lens 35 Visible Light Cut Filter 36 Slit 37 Focusing Light Receiving Element 38 Translucent Mirror DESCRIPTION OF SYMBOLS 9 Half mirror 40 Infrared light emitting diode 41 Corneal endothelial cell imaging device 42 Anterior ocular segment observation optical system 43 Alignment index projection optical system 44 Visible light transmission / infrared reflection mirror 45 Corneal endothelial cell imaging device 46 Turning frame 47 Corneal endothelial cell imaging device 48 Rotating frame 49 Rotating frame C Predetermined point (center point of guide rail)
D Distance between the corneal apex T (on the anterior segment) and the imaging part M E Eye to be examined F Focus point H (Fixed light) Reference horizontal line M Imaging part (specified position)
N normal line P fixation height position R radius of curvature of cornea S optical reference axis Sb optical reference axis bent portion T cornea apex

Claims (10)

An ophthalmic examination apparatus for examining an arbitrary position in an anterior segment of an eye to be examined,
Inspection optical system for eye examination;
An optical reference axis positioning mechanism that aligns the direction of the optical reference axis with the normal of the arbitrary position on the corneal surface of the eye to be examined by tilting at least one of the tilt and linear movement of the optical reference axis of the inspection optical system. Ophthalmic examination equipment. An anterior ocular segment observation optical system having a camera that images the anterior ocular segment of the eye to be examined;
Position designation means for designating a portion to be examined on the anterior segment image captured by the anterior segment observation optical system;
Normal direction calculating means for calculating the normal direction of the position designated by the position designation means based on the relative positional relationship between the corneal vertex position on the anterior segment image and the designated position. The ophthalmic examination apparatus according to claim 1.   Using a predetermined radius of curvature of the cornea of the human eye, a plurality of predetermined points on the anterior segment image of the human eye determined in advance and the direction of the normal on the cornea at the predetermined point are calculated. The ophthalmic examination apparatus according to claim 1, wherein the ophthalmic examination apparatus is stored as normal data, and a normal direction at a specified position is determined by selecting and specifying the predetermined point. The inspection optical system is
An illumination optical system for illuminating the anterior segment of the subject's eye from the diagonally front with illumination light;
A photographing optical system for receiving reflected light reflected by the anterior segment of the illumination light;
4. The optical reference axis according to claim 1, wherein the optical reference axis is an axis in a direction that bisects an intersection angle between an illumination optical axis of the illumination optical system and a photographing optical axis of the photographing optical system. Ophthalmic examination equipment.   The optical reference axis positioning mechanism forms a right angle with each other, including a first mechanism for tilting the optical reference axis in a plane, a second mechanism for tilting in a plane perpendicular to the plane, and a direction toward the eye to be examined. The ophthalmic examination apparatus according to any one of claims 1 to 4, further comprising a third mechanism that advances and retracts in each of the three axial directions. An anterior ocular segment observation optical system having a camera that images the anterior ocular segment of the eye to be examined;
An alignment index projection optical system that irradiates the eye to be examined with alignment index light along the observation optical axis of the anterior ocular segment observation optical system,
The anterior ocular segment observation optical system is configured to detect the corneal apex position of the anterior ocular segment when the camera receives a reflected image from the eye surface of the alignment index light,
6. The ophthalmic apparatus according to claim 5, wherein the third optical mechanism is configured to align the inspection optical system with respect to the eye to be examined by moving the reflected image so as to fall within a predetermined range of the imaging screen of the camera. Inspection device. A position fixing unit for fixing the eye to be examined at a predetermined position;
The first mechanism is configured to tilt the inspection optical system with a point set so as to substantially correspond to the center point of the anterior segment spherical surface of the eye to be examined in the position fixing unit,
The ophthalmic examination apparatus according to claim 5 or 6, wherein the second mechanism has a tiltable reflecting member for reflecting the optical reference axis to bend its direction. A position fixing unit for fixing the eye to be examined at a predetermined position;
The first mechanism is configured to tilt the inspection optical system with a point set so as to substantially correspond to the center point of the anterior segment spherical surface of the eye to be examined in the position fixing unit,
The second mechanism is configured to tilt the inspection optical system with a point set so as to substantially correspond to the center point of the anterior surface spherical surface of the eye to be examined in the position fixing unit. The ophthalmic examination apparatus according to claim 5 or 6. A fixation target for keeping the direction of the eye to be examined in a single direction by fixing the eye to be examined is provided in a fixed and immovable state, and the reflecting member reflects a part of the light and transmits a part of the light. Composed of a translucent mirror member,
Since the fixation target is disposed behind the translucent mirror member when viewed from the eye to be inspected at the position fixing portion, the fixation eye passes through the translucent mirror member and fixes the fixation target. The ophthalmic examination apparatus according to claim 7, which can be viewed.   The anterior ocular segment observation optical system is provided in an immovable fixed state, and the anterior ocular segment observation optical system is disposed behind the translucent mirror member as viewed from the eye to be examined in the position fixing unit. The optical axis of the anterior ocular segment observation optical system is configured so as to be along the axis from the eye to the fixation target between the translucent mirror member and the eye to be examined in the position fixing unit. The ophthalmic examination apparatus according to claim 9.

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