公开(公告)号：US5294075A

公开(公告)日：1994-03-15

申请号：US752109

申请日：1991-08-28

申请人： Edward J. Vertatschitsch ,  Gregory L. Abbas ,  Michael de La Chapelle ,  J. Doyle McClure

发明人： Edward J. Vertatschitsch ,  Gregory L. Abbas ,  Michael de La Chapelle ,  J. Doyle McClure

IPC分类号： B64D45/00 ,  G01K11/32 ,  G01S17/32 ,  B64C5/00

CPC分类号： G01S17/32 ,  G01K11/32

摘要： An optical position sensing system for sensing the position of a displaceable element. An electro-optical unit outputs a modulated optical signal and a chirped rf signal. The envelope of the modulated optical signal has a phase that has a known relation to the phase of the chirped rf signal. The electro-optical unit is coupled to a light guide element and receives and transmits the modulated optical signal along an optical path for reflection off a surface of the displaceable element in order to provide a position sensing optical signal. A reference reflecting element is disposed in the optical path upstream of the displaceable element for partially reflecting the transmitted modulated optical signal in order to provide a reference optical signal. A transducing unit receives the rf signal at one input and has another input optically coupled for receiving the position sensing optical signal and the reference optical signal which have, respectively, first and second time delays with respect to the chirped rf signal. The transducing unit produces a multi-frequency electrical signal which includes first and second frequencies corresponding to the first and second time delays, respectively. A position detecting unit coupled to the output of the transducing unit processes the multi-frequency signal in order to determine a difference frequency corresponding to the difference between the first and second frequencies and representing the position of the displaceable element.

摘要翻译： 一种光学位置检测系统，用于感测位移元件的位置。 电光单元输出调制光信号和啁啾rf信号。 调制光信号的包络具有与啁啾rf信号的相位已知关系的相位。 电光单元耦合到光导元件，并且沿着光路接收并发射调制的光信号，用于反射离开可移位元件的表面，以便提供位置感测光信号。 参考反射元件设置在可移动元件的上游的光路中，用于部分地反射发射的调制光信号，以便提供参考光信号。 转换单元在一个输入处接收rf信号，并且具有光耦合的另一输入，用于接收相对于啁啾rf信号分别具有第一和第二时间延迟的位置感测光信号和参考光信号。 转换单元产生分别包括对应于第一和第二时间延迟的第一和第二频率的多频电信号。 耦合到转换单元的输出的位置检测单元处理多频信号，以便确定与第一和第二频率之间的差对应的差频，并表示可移位元件的位置。