| 摘要 |
PURPOSE:To perform integration by dividing the time when light is projected to two periods, the first half and the second half, and to correct background light in order to reduce erroneous range-finding caused by the change of the background light being projected while performing the range-finding of a moving body. CONSTITUTION:When a luminous flux is projected toward an object by an IRED, reflected light from the object is received by a photodetector 14, and a photoelectric conversion signal is outputted. 1st and 2nd integration circuits 19 and 20 perform the integration by dividing the photoelectric conversion signal to the first half and the second half during the time when the light is projected by the IRED by switches 17 and 18 switched under control from a timing circuit 25. Then, correction arithmetic operation corresponding to the change of the background light during the time when the light is projected is performed based on the output of the 1st and the 2nd integration circuits 19 and 20 in an addition circuit 21, a subtraction circuit 22, a double circuit 23 and an addition circuit 24. |
