Konan Inc.

Yoshizo Ikegami

Tatsuya Kasahara

Yoichi Hamada

A method for displaying a photographing point of a cornea which is used in an apparatus for obtaining video images of corneal cells. The apparatus includes (a) first optical assembly having a video camera provided in front of a subject eye for observing and obtaining video images of a frontal portion of the subject eye, (b) second optical assembly for projecting slit light to an eyeball surface of the subject eye, and (c) third optical assembly for magnifying a video image of a subject portion of the eye produced based of a projection of the slit light by the second optical assembly and for guiding the image to the video camera so that the magnified video image of the subject portion of the eye is photographed by the video camera; and the displaying method comprises the steps of (i) determining a first coordinate with respect to the video image of the frontal portion of the subject eye, which corresponds to the subject portion of the eye photographed, (ii) determining a second coordinate, which corresponds to a pupil center in the video image of the frontal portion of the subject eye; and (iii) marking and displaying the photographing point of the cornea in the video image of the frontal portion of the subject eye by calculation based upon the first and second coordinates.

Method for displaying a photographing point of a cornea in an apparatus

An apparatus for obtaining visual images of cornea cells, which allows magnified images of cornea cells to be easily obtained at required important sites of the cornea cells including a center site one by one by changing over the site, by leading the view axis of the subject and without requiring the decision of the operator in obtaining magnified images of cornea cells. Also, in order to allow a correct imaging site to be known, an imaging position mark is displayed at a correct position on the eyeball surface on the eye-front imaging screen of a TV camera. For illuminating through a slit an eyeball surface (2) and forming a magnified image of cornea cells of the subject part on an image-receiving surface (34) of a TV camera (35) via a magnification-imaging optical system based on the illumination light, a center view target and a plurality of view targets of required positions around the center view target are set by visible-light emitting diodes (27), (27.sub.1) and these light-emitting diodes are arranged to be switchable one by one by a center lighting switch and a peripheral lighting-change switch. By this arrangement, an magnified image of the cornea cells of required positions can be easily obtained by leading the view of the subject.

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Nishinomiya, Japan

Yoshizo Ikegami