| 摘要 |
<p>A laser driver (4) causes a semiconductor laser (1) to operate such that a first oscillation period of monotonically increasing the oscillation wavelength and a second oscillation period of monotonically decreasing the oscillation wavelength alternately exist. A photodiode (2) converts laser light emitted from the semiconductor laser (1) and return light from a measurement target (12) into electrical signals. A counting unit (13) counts the number of interference waveform components obtained from an output signal from the photodiode (2) in each of the first oscillation period and the second oscillation period. A computing device (9) calculates the distance to the measurement target (12) and the velocity of the measurement target (12) from a shortest Lasing wavelength and a longest Lasing wavelength in a period during which the counting unit (13) counts the number of interference waveform components and the counting result obtained by the counting unit (13). This makes it possible to measure the distance to the moving measurement target (12) and the velocity of the measurement target (12).</p> |
