| 摘要 |
<p>A distance measuring device optically beats down a light from a light source that oscillates a plurality of frequencies using an optical modulator, and detects a phase thereof at a low frequency to enhance a measurement precision without any increase in the device costs. The distance measuring device includes a light source that oscillates a light having a plurality of different frequencies, the optical modulator that modulates frequencies of the light from the light source and the light from the light source which has been applied to an object to be measured, and then reflected therefrom, an oscillator that inputs a voltage signal to the optical modulator, a detector that detects an optical signal modulated by the optical modulator, and a distance calculation circuit that calculates a distance according to the phase of the optical signal detected by the detector.</p> |
