| 摘要 |
PURPOSE:To attain the reduction in cost and simplification of a range-finding circuit. CONSTITUTION:Pulsative light is projected on an object, an optical signal from the object is integrated by the light receiving circuits 3 and 20 and 3 and 30 on a long distance side and on a short distance side until a constant voltage is obtained and the number of projecting times at this time is counted. A distance up to the object is calculated from the obtained two count values. The distance up to the object is calculated from the number of the projecting times, so that it is unnecessary that a voltage between the terminal of an integration capacitor is converted into a digital signal and highly accurate range-finding can be executed by a more simple and inexpensive circuit. |
