Patent attributes
Stimulus light is projected from a stimulus light source onto an ocular fundus of an eye under examination to locally stimulate the retina in order to perform a biological examination. During a biological examination, first background light is projected from an illumination light source via an objective lens, and second background light is projected from a light source from the periphery of the objective lens onto the ocular fundus. During alignment prior to a biological examination, the first background light is turned off and the second background light is projected onto the ocular fundus. During observation of the ocular fundus, the first background light projected onto the fundus is blocked, so that fundus observation or eye fixation is not disturbed by the background light. This enables accurate alignment to be carried out. Since the examinee's eye is irradiated with the second background light from the periphery of the objective lens in preparation for a biological examination, the examinee's eye can sufficiently adapt to the light during a biological examination, ensuring a reliable biological examination.
