Corneal endothelial cell photographing apparatus

Abstract

A corneal endothelial cell photographing apparatus comprises: a main unit including: an illumination optical system for illuminating illumination light from an illumination light source toward a cornea of an examinee's eye from an oblique direction; an imaging optical system for obtaining a corneal endothelial cell image by receiving, through an imaging element, reflection light from the cornea including corneal endothelial cells; and a fixation optical system including a plurality of fixation targets and for guiding a fixation direction of the examinee's eye; a drive unit to relatively move the main unit with respect to the examinee's eye; a serial photographing unit to obtain endothelial images in series at different photographing positions in previously set up-and-down and right-and-left directions; and a monitor to display the obtained endothelial image.

What is claimed is: 
     
         1 . A corneal endothelial cell photographing apparatus comprising:
 a main unit including:
 an illumination optical system for illuminating illumination light from an illumination light source toward a cornea of an examinee's eye from an oblique direction; 
 an imaging optical system for obtaining a corneal endothelial cell image by receiving, through an imaging element, reflection light from the cornea including corneal endothelial cells; and 
 a fixation optical system including a fixation target and for guiding a fixation direction of the examinee's eye; 
   a drive unit operable to relatively move the main unit with respect to the examinee's eye in a three-dimensional rectangular coordinate system having a first axis in a back-and-forth direction toward and away from the examinee's eye, a second axis in an up-and-down direction relative to the examinee's eye, and a third axis in a right-and-left direction relative to the examinee's eye;   a controller configured to operate the main unit to obtain endothelial photographic images in series at a plurality of photographing points of a preset photographing pattern on the cornea by way of relative movement between the main unit and the cornea in at least one of the up-and-down direction and the right-and-left direction, wherein the photographing points of the preset photographing pattern are different on the cornea from one another in at least one of the up-and-down direction and the right-and-left direction; and   a display control unit for causing a monitor to display the obtained endothelial image, wherein   the controller previously sets a photographing range on the cornea including the pattern of the photographing points that are different from one another in at least one of the up-and-down direction and the right-and-left direction, and   the controller is configured to operate the drive unit to move the main unit in the up-and-down direction and the right-and-left direction and to operate the main unit to serially obtain endothelial images at the plurality of photographing points in the previously set photographing range.   
     
     
         2 . The corneal endothelial cell photographing apparatus according to  claim 1 , further including a Z alignment detection sensor for detecting an alignment state in the back-and-forth direction with respect to the cornea at each photographing point, and
 wherein the controller is configured to control the drive unit based on a detection result of the Z alignment detection sensor to adjust a back-and-forth position of the main unit at each photographing point.   
     
     
         3 . The corneal endothelial cell photographing apparatus according to  claim 1 , further including a setting unit to be operated by an examiner to set the photographing range on a corneal image displayed on the monitor. 
     
     
         4 . The corneal endothelial cell photographing apparatus according to  claim 1 , wherein the controller moves the main unit in the back-and-forth direction at each photographing point, and serially obtains endothelial images at different photographing positions in the back-and-forth direction through the imaging element. 
     
     
         5 . The corneal endothelial cell photographing apparatus according to  claim 1 , further including an XY alignment detection sensor for detecting an alignment state in the up-and-down direction and the right-and-left direction with respect to a corneal center of the examinee's eye,
 wherein the controller controls driving of the drive unit based on a detection result of the XY alignment detection sensor to move the main unit to the photographing points while obtaining endothelial images at the photographing points.   
     
     
         6 . The corneal endothelial cell photographing apparatus according to  claim 1 , wherein the controller is configured to sequentially change the photographing points clockwise or counterclockwise. 
     
     
         7 . The corneal endothelial cell photographing apparatus according to  claim 1 , wherein, when serial photographing in the up-and-down direction and the right-and-left direction is to be performed, the controller is configured to detect a relative position of the main unit with respect to the eye at each of the photographing points and perform automatic alignment to each of the photographing points. 
     
     
         8 . The corneal endothelial cell photographing apparatus according to  claim 7 , wherein the controller is configured to perform automatic alignment in the back-and-forth direction to each of the photographing points. 
     
     
         9 . The corneal endothelial cell photographing apparatus according to  claim 8 , wherein the controller is configured to perform automatic alignment in at least one of the up-and-down direction and the right-and-left direction to each of the photographing points.