| 摘要 |
PROBLEM TO BE SOLVED: To provide an ophthalmologic device capable of judging which eye, right or left, is to be checked without being influenced by brightness and disturbance light from sunlight or an incandescent electric lamp. SOLUTION: A subject detecting means 8 for detecting whether an area of the body of a subject exist within a prescribed distance is provided on an ophthalmologic device. This means 8 is constituted by a light emitting element 8d, a light receiving element 8e, an oscillation circuit 8f, a driver 8g and a high-pass circuit 8h. A signal of a frequency of 1 kHz outputted from the oscillation circuit 8f is inputted to the driver 8g, and the driver 8g emits an infrared index light which goes on and off at a frequency of 1 kHz from the light emitting element 8d based on this signal. The light receiving element 8e receives a reflected light which is emitted from the light emitting element 8d and irradiated to the subject, and generates a signal corresponding to it. The high-pass circuit 8h cuts frequency component lower than 1 kHz, and outputs a signal of a frequency more than 1 kHz to a control circuit C1 as a detected signal.
|
