| 摘要 |
PROBLEM TO BE SOLVED: To reduce the influence of transient response by apexes of a choppy wave. SOLUTION: The physical quantity sensor includes: a semiconductor laser 1; a laser driver 4 for supplying the semiconductor laser 1 with a drive current having a waveform in which the maximum part and minimum part of a choppy wave are rounded; detection means (a photodiode 2 and a current-voltage conversion amplifier 5) for detecting an electric signal including an interference waveform which is generated by the self-coupling effect of the laser light emitted from the semiconductor laser 1 and the return light from an object under measurement 10; and measuring means (a filter circuit 6, a counter 7, and an arithmetic unit 8) for measuring the physical quantity of the object under measurement from information on the interference waveform. COPYRIGHT: (C)2009,JPO&INPIT |
