| 摘要 |
<p>Disclosed is a method and a device for light propagation time measurement, wherein a light signal is transmitted from at least one transmitter into a light path via a retroreflective object to a receiver for detecting the alteration of the first signal, presence, and/or distance of the object, the received signal being determined from the path and compared with a second signal produced without the light path to achieve a comparison value, which regulates amplitude values of the transmitted signal and/or of the second signal, a clock change signal corresponding to the light propagation time between received signal and second signal is detected cyclically, a difference value being determined by comparing change signals between received signal and second signal , the difference value being altered by means of a phase shifter , delay of the phase shifter that occurred given a minimal difference value determining the light propagation time.</p> |
