| 摘要 |
<p>PROBLEM TO BE SOLVED: To suppress the irradiation of an eye to be examined with an unnecessary quantity of light, by altering the input quantity of light to a photodetector receiving the fundus reflected light of illumination light. SOLUTION: A system control part 50 rotates a disc slit 39 through a slit motor control circuit 57 and an aperture part and a shading part become 1:1 by the rotation of the disc slit 39 and the irradiation quantity of tracking light to the fundus Ea is set so that a time ratio of lighting and lights-off in a flashing cycle becomes 1:1 to illuminate the fundus Ea in an on-and-off state. Since the quantity itself of light per a unit time is not reduced, the reflection brightness of tracking light or measuring light at the fundus Ea is not lowered and an irradiation light can be reduced without exerting adverse effect on the visibility of a measuring indicator and the whole exposure quantity of laser beam to the fundus Ea of an eye E to be examined can be suppressed.</p> |
