Structure Design Of Optical Grating Displacement Probe

With the rapid development of modern sensor technology and micro/nano measurement technology, the demand and research for high-precision displacement measurement has increased dramatically. Optical grating displacement sensor ,with its various unique virtues of long range, high precision and resolution, capability of dynamic measurement application, easily digital implementation, convenience for fixing and adjusting, etc, is attracting the attention from people more and more popularly. The optical grating probes sold in markets are still predominantly foreign products, which have expensive cost and are difficult for popularization. So developing low cost high-precision optical grating probes has great practical value and good application prospect.An optical grating displacement probe was independently designed in this degree thesis. In the course of structure design, Abbe's principle was followed on the one hand; On the other hand, based on the principle of dynamic force balance, a structure design method of maintaining approximately constant measuring force in a certain range measurement was put forward. An experimental equipment involving motor drive and support structure was developed. A characteristic calibration experiment of the probe was completed at last. The test results indicated that the probe showed the measurement uncertainty of sub micrometer in the reading range of 10mm, and its manufacturing cost was only about one fifth of the prices of products with the same characteristics. If the mechanical processing accuracy of the parts were further enhanced, the precision of the optical grating probe would be further improved.