Laser-based displacement measurement of a remote object

摘要

Displacement measurement is necessary in many different areas ranging from mechanical machining, building construction, land survey, ect. Displacement can be measured by traditional mechanical methods and optical means. Optical displacement measuring systems have the advantages of noncontact, high resolution, fast response, and more importantly being remote. We describe in this paper a laser-based displacement measuring system which can detect displacement or deflection of a remote object. The system consists of a laser source and a linear or area detector array. In order to achieve a long distance remote measurement, the laser beam is first collimated, and directed to the detector array which is attached to the object to be measured. The relative movement between the laser source and the detector will provide a measure to the displacement or deflection of the object. Novel signal and image processing algorithms have been developed to enhance the resolution and accuracy of the system. Techniques for long distance signal and data transmission have also been investigated. The design details of the system are described and experimental test results are presented. The features of the current displacement measuring system include high resolution and accuracy while still keeping a relatively simple structure and a low cost. The developed system will serve as a useful tool for many different engineering applications.