Zhejiang Sci-Tech University

Enzheng Zhang

Liping Yan

Benyong Chen

Bin Xu

A laser heterodyne interferometric straightness measurement apparatus and method with six DOFs determination includes a part for determining the straightness and its position based on laser heterodyne interferometry and a part for error determination and compensation. The optical path for determination of four DOFs errors including three common beam-splitters, a polarizing beam-splitter, a planar mirror, a convex lens, a position-sensitive detector and two quadrant detectors is added in the optical configuration of the part for determining the straightness and its position based on laser heterodyne interferometry.

Laser heterodyne interferometric straightness measurement apparatus and method with six DOFs determination

The present invention discloses a processing method for laser heterodyne interferometric signal based on locking edge with high frequency digital signal. A reference signal and a measurement signal of heterodyne interferometer, after being processed by photodetector, signal amplifier, filtering circuit, voltage comparator and high frequency digital edge locking module, are transferred to pulse counting synchronized latching processing module, to obtain entire cycle interference fringe numbers and filling pulse numbers in one interference fringe cycle, of the reference signal and the measurement signal; the numbers are transferred to a computer to obtain displacement and speed of a measured object; usage of a high frequency digital pulse signal to lock the rising edge of laser heterodyne interferometric signal can improve the gradient of the rising edge of interference signal and eliminate wrong pulse caused by noises, and improve the accuracy and stability of the processing for the following signals.

Growing community of inventors

Zhejiang, China

Enzheng Zhang