公开(公告)号：US4872751A

公开(公告)日：1989-10-10

申请号：US144495

申请日：1988-01-14

申请人： Michael Hercher

发明人： Michael Hercher

IPC分类号： G01D5/38

CPC分类号： G01D5/38

摘要： A lateral movement sensing system which utilizes a two-frequency laser to provide two laser beams to illuminate a surface of a laterally moveable body. A beam splitter divides the two-frequency laser into two beams, and the system detects the modulation frequency of the scattered light when the laterally moveable body is moving. This detected modulation frequency is compared to the frequency difference between the two beams. The phase difference between the detected modulation frequency and the difference frequency represents units of lateral displacement of the laterally moveable body.

摘要翻译： 一种横向移动感测系统，其利用双频激光器来提供两个激光束以照射横向可移动体的表面。 分束器将双频激光器分成两束，当侧向移动体移动时，系统检测散射光的调制频率。 将该检测出的调制频率与两个波束之间的频率差进行比较。 检测出的调制频率和差频之间的相位差表示横向移动体的横向位移的单位。

公开(公告)号：US4711573A

公开(公告)日：1987-12-08

申请号：US940196

申请日：1986-12-12

申请人： Geert Wijntjes ,  Michael Hercher

发明人： Geert Wijntjes ,  Michael Hercher

IPC分类号： G01J3/453 ,  G01J3/45

CPC分类号： G01J3/4535

摘要： An improved mirror alignment control for dynamically aligning the reflecting mirrors bounding the optical path in an interferometer comprises a closed loop servo control which utilizes a two frequency laser beam to provide phase comparison between beams traversing differing portions of the optical paths in the interferometer to determine alignment of the mirrors, said phase comparison providing a correction signal to direct multi-axial alignment of at least one of the mirrors.

摘要翻译： 改进的反射镜对准控制用于动态对准在干涉仪中包围光路的反射镜包括闭环伺服控制器，该控制器利用两频激光束来提供穿过干涉仪中光路不同部分的光束之间的相位比较，以确定对准 所述相位比较提供校正信号以指导至少一个反射镜的多轴对准。

公开(公告)号：US4672618A

公开(公告)日：1987-06-09

申请号：US884872

申请日：1986-07-09

申请人： Geert Wijntjes ,  Michael Hercher

发明人： Geert Wijntjes ,  Michael Hercher

IPC分类号： H01S3/139 ,  H01S3/13

CPC分类号： H01S3/1396 ,  H01S3/139

摘要： A method and means for stabilizing the difference in frequencies between the frequency components of a two frequency laser beam influenced by Zeeman effect frequency splitting, accurately determines the frequency separation independently of the individual frequencies or intensities of either of the frequency components. Frequency stabilization is accomplished by mechanical and thermal adjustments to the lasing chamber length of the laser by a closed loop servo control referencing the frequency difference between laser beam components and a reference signal having a frequency equal to the desired frequency difference.

摘要翻译： 用于稳定受塞内影响频率分割影响的双频激光束的频率分量之间的频率差异的方法和装置，可以独立于频率分量中的任一个的各个频率或强度精确地确定频率分离。 通过使用参考激光束分量之间的频率差和具有等于期望频率差的频率的参考信号的闭环伺服控制来对激光器的激光室长度进行机械和热调节来实现频率稳定。