| 摘要 |
An electronic distance measuring instrument comprises a distance measuring optical path (13), an internal reference optical path (10), a pulsed light emitting light source (5) for emitting a pulsed light, a pulsed light guiding means for directing the pulsed light emitted from the pulsed light source toward the distance measuring optical path as a distance measuring pulsed light and for directing the pulsed light toward the internal reference optical path as an internal reference pulsed light, a photodetector (6) for detecting the distance measuring pulsed light and the internal reference pulsed light and emitting a photodetection signal, and a measuring unit (4) for calculating the distance to an object to be measured based on the photodetection signal from the photodetector. The electronic distance measuring instrument is arranged to perform a coarse distance measurement based on the difference in the photodetection time between the internal reference pulsed light and the distance measuring pulsed light reflected from the object to be measured, to carry out a Fourier function transform on the photodectection waveform of the internal reference pulsed light outputted by the photodetector and the photodetection waveform of the distance measuring pulsed light, respectively to separate the waveforms into a plurality of frequency components, to obtain the phase difference for each of the frequency components acquired, to perform a fine distance measurement based on the time difference acquired from the phase difference and to measure the distance to the object to be measured by adding the result of the coarse distance measurement to the result of the fine distance measurement. |
