Ophthalmic Photographing Apparatus

Abstract

To provide an ophthalmic photographing apparatus capable of checking a measurement (photographing) position of a tomographic (cross-sectional) image of a fundus on a front (surface) image of the fundus. The ophthalmic photographing apparatus has a first optical system for obtaining a tomographic image of a fundus by optical coherence tomography using low coherent light, a second optical system for obtaining a visible front image of the fundus, a third optical system for obtaining an infrared front image of the fundus, a monitor, setting means which sets a line for obtaining a two-dimensional tomographic image of the fundus on the infrared front image displayed on the monitor, and control means which establishes a positional correspondence between the infrared front image on which the line is set and the visible front image, and displays a line on the visible front image displayed on the monitor.

1 . An ophthalmic photographing apparatus comprising:
 a first optical system for obtaining a tomographic image of a fundus by optical coherence tomography using low coherent light;   a second optical system for obtaining a visible front image of the fundus;   a third optical system for obtaining an infrared front image of the fundus;   a monitor;   setting means which sets a line for obtaining a two-dimensional tomographic image of the fundus on the infrared front image displayed on the monitor; and   control means which establishes a positional correspondence between the infrared front image on which the line is set and the visible front image, and displays a line indicating a measurement position of the two-dimensional tomographic image on the visible front image displayed on the monitor.   
     
     
         2 . The ophthalmic photographing apparatus according to  claim 1 , wherein the control means establishes the positional correspondence between the infrared front image and the visible front image by extracting characteristic points in the infrared front image and the visible front image and matching the characteristic points by image processing. 
     
     
         3 . The ophthalmic photographing apparatus according to  claim 1 , wherein the first optical system includes scanning means which performs two-dimensional scanning of measurement light with respect to the fundus, and optical path changing means which changes an optical path length of reference light in synchronization with the scanning of the measurement light by the scanning means. 
     
     
         4 . The ophthalmic photographing apparatus according to  claim 3 , wherein the first optical system also serves as the third optical system and obtains a three-dimensional tomographic image and the infrared front image of the fundus. 
     
     
         5 . The ophthalmic photographing apparatus according to  claim 1 , wherein the third optical system includes an image-pickup element which measurement light of the first optical system enters. 
     
     
         6 . An ophthalmic photographing apparatus comprising:
 a first optical system for obtaining a three-dimensional tomographic image of a fundus by optical coherence tomography using low coherent light;   a second optical system for obtaining a visible front image of the fundus;   a monitor;   setting means which sets a line for obtaining a two-dimensional tomographic image of the fundus on the visible front image displayed on the monitor; and   control means which obtains the two-dimensional tomographic image from the three-dimensional tomographic image based on the set line and displays the two-dimensional tomographic image on the monitor.   
     
     
         7 . The ophthalmic photographing apparatus according to  claim 6 , wherein the control means establishes a positional correspondence between the visible front image and the three-dimensional tomographic image by extracting characteristic points in the visible front image and the three-dimensional tomographic image and matching the characteristic points by image processing. 
     
     
         8 . The ophthalmic photographing apparatus according to  claim 6 , wherein the first optical system includes scanning means which performs two-dimensional scanning of measurement light with respect to the fundus, and optical path changing means which changes an optical path length of reference light in synchronization with the scanning of the measurement light by the scanning means.