Hardware Design And Accuracy Evaluation Of Photoelectric Autocollimator Based On Invariant Light-distance

Micro angle measurement technique is widely used in machinery, optics, aviation, aerospace, marine and other fields, High-precision measurement of micro angle is one of the key areas in the geometry measurement research. In this dissertation, based on the principle of invariant light-distance photoelectric autocollimator, the main research contents about research and development of the instrument are as follows.Firstly, based the principle of self-collimation, the framework of the invariant light-distance photoelectric autocollimator is designed. Four components including clamping structure, optical system, photoelectric detector, the signal processing system were designed. Focuses on the design of optical systems and discuss the principle of optical detection from the mathematical point of view.Secondly, optical devices of the photoelectric autocollimator are selected .The analysis of the final beam quality and distribution of the light intensity was done in the paper. Based the research of the response speed, spectral characteristics and signal quality of the Photoelectric converter,a four quadrant silicon photo detector was chosen as the Photoelectric converter. The Mathematical formula for the received signal was given.Thirdly, an elaboration of the invariant light-distance measurement system circuit design and software platform was given. Design of the signal amplifier and signal extraction circuit to help the optical receiver receives the current signal into a voltage signal which can be collected. Then the high-speed acquisition card is used to do the sampling and A / D conversion to extract the useful signal and output in the computer.Finally, using the high-precision photoelectric autocollimator to calibrate the voltage signal which collected by this measuring system ,then find the corresponding relationship between voltage and angle. Re-use of the high-precision photoelectric autocollimator compared with the measurement system, and the measurement results are analyzed, the same time, error analysis, and establish error model .The experiment proved that the measurement accuracy of the measurement system meet the design requirements.