Optical distance measuring instrument
Optical distance measuring instrument
复制标题
光学测距仪
DOI：
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发表时间：
1973
期刊：
影响因子：
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通讯作者：
J. Abshire
中科院分区：
文献类型：
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作者：
J. Abshire
一种光学仪器(10)，例如稳定性监视器或目标测距仪，使用不稳定激光器(12)来投射具有两个自然发生的纵模分量的相干光的复合光信号。分束器(24)将信号分成指向一个光电探测器(28)的参考光束(26)和照射远距离目标(44)并从远处目标(44)反射到与第一光电探测器光学隔离的第二光电探测器(52)的透射光束(42)。两个光电探测器均根据平方律原理操作，以提供调制频率等于激光器 (12) 投射的光信号的两个纵模分量的频率之间的间隔的电信号。目标的轻微移动可以通过电监控光电探测器提供的两个信号之间的相位差来检测和测量，并且借助微处理器(132)通过以迭代系列增量移动谐振腔的长度来改变纵向模式之间的间隔来测量目标的范围。
An optical instrument (10), such as a stability monitor or a target range finder, uses an unstabilized laser (12) to project a composite optical signal of coherent light having two naturally occurring longitudinal mode components. A beamsplitter (24) divides the signal into a reference beam (26) which is directed toward one photodetector (28) and a transmitted beam (42) which illuminates and is reflected from a distant target (44) onto a second photodetector (52) optically isolated from the first photodetector. Both photodetectors are operated on the square law principle to provide electrical signals modulated at a frequency equal to the separation between the frequencies of the two longitudinal mode components of the optical signal projected by the laser (12). Slight movement of the target may be detected and measured by electrically monitoring the phase difference between the two signals provided by the photodetectors and the range of the target measured with the aid of microprocessor (132) by changing the separation between the longitudinal modes by shifting the length of the resonator cavity in an iterative series of increments.