Research Of Key Technologies On New Type Of Optical Encoder

Optical encoder is widely used to detect displacement in a high-precision position control system. Based on high-precision radial grating as key component, the optical encoder is able to convert the input mechanical value into corresponding digital value through photoelectrical technology. The encoder is widely applied in many different fields such as radar, photoelectrical theodolite, precise angle measurement devices, robots,CNC machine tools and high precision closed loop timing system because of its high resolution, wide measurement range, high precision, reliability, easy to maintain, simple structure and with high cost performance. So it is the ideal angle sensor in the automatic equipment.With the development of industrial automation and aerospace technology, the urgent requirement of optical encoder precision and environmental adaptability is increasing. it required the ability of tolerance the high temperature and vibration, shock a corrosion resistance. The encoder can operate in bad environment normally. At present, K9glass, float glass, stainless steel and film are used to make code disc, they can not meet the above requirements.This paper analyzes the working principle of the traditional optical encoder, and points out its limitations at the same time. The PC grating disc is developed used a new making technology by analyzing the optical characteristic of part optical resin, especially Polymethylmecrylate, Polycarbonate, Polystyrene and based on researching actual photolithography copy technology.To improve the reliability of the system, the paper focused analysis on several key technologies of optical encoder which is based PC material code disc, it not only study the effects on beam collimation precision optical encoder, shock resistance, radial force and the axial force and other characteristics, but study the manufacturing process of optical resin material and the pattern design of the slit and the code disc, it also use the improved coding matrix to encode to improve the traditional coding theory, Finally it analyze the connection between the measuring accuracy and the slit gap, selecting the most appropriate system for the slit width. At last the paper design the PC code disc and the optical encoder system, achieve the hardware circuit of the photoelectrical system, signal acquisition system and data transmission system, write the software of the signal processing and data transmission at the same time. it shows the system results and analyzes the experiment results, and proposes the improved scheme.