微小光学器件装配系统与实验研究

The process of precisely assembling a prism and a phototube onto the resonator of a ring laser gyroscope is called beam-coupling. This is a key procedure in the production of ring laser gyroscopes. Traditional manual beam-coupling is unable to satisfy the demands of ring laser gyroscope assembly, due to the inefficiency and lack of stability associated with the process. An automatic beam-coupling assembly system is therefore developed based on the analysis of beam-coupling principles. This method involves the application of beam-coupling mechanisms, the processing of the beam-coupling signals, vision detection and the use of a control module. Based on the operation characteristics of beam-coupling, a two-arm coordinated movement mechanism is designed to ensure the accuracy of operation and to simultaneously improve the efficiency of the assembly process. A low pass filter based on the Sallen-Key is used to remove noise since the beam-coupling signal is easily disturbed. The control module performs coarse adjustments of the optical prism using machine vision and uses the analytic hierarchy process (AHP) to evaluate the best position and orientation of the optical device. This is achieved by combining a plurality of evaluation parameters to realize automation of the optical assembly. The experimental results show that the developed laser-gyro-assembly system can successfully perform accurate assembly of optical devices.