摘要 |
PURPOSE:To execute an active range-finding action without using an analog IC for range-finding as to a camera using a CPU by connecting a photodetector and an integration circuit with the port of the CPU and executing the range- finding in which stationary light is eliminated by the integral of the stationary light and integrated time at the time of IRED emission. CONSTITUTION:A luminous flux projected by a light projecting part 21 is reflected from a range-finding object, received by a photoelectric converting part 22, and converted to a current signal, and the photoelectric output is integrated at the integration circuit 23. And an integrated voltage obtained by the integration circuit 23 is compared with a specified value, so that it is inverted when it is over the specified value, and the integration circuit 23 is initialized so that time from this initialization till output is inverted is measured, and a distance to the range-finding object is detected based on the measured time when the light projecting part 21 does not project light and the measured time when the light projecting part 21 projects light at the CPU 14. |