Design Of High-speed Grating Electrical System And Research For Subdivision

With the development of modern processing and measurement technology, thedemands on the length and the displacement measurement accuracy continuouslyincreased, and it also requires that the measurement results can be easily exportedand data processing. Grating measurement technique with high measurementaccuracy, and combined with electronic technology and computer technology, itcan achieve high-speed and automated measurement and to be a precisionmeasurement devices widely used in instrumentation and machine tools. This paperresearched on the electrical system of grating measuring. On this basis, the eightsegments of the grating signal and the digital output had been achieved.Firstly, this article described the development status of the grating at homeand abroad and the basic principles of the grating measurement system thenintroduced and summarized the common grating subdivision method. Depending onthe circumstances of the optical signal, and analyze and compare multiplephotoelectric converter, we choose a PIN photodiode as a photoelectric converter,at the same time, we design a low-noise preamplifier circuit and analysis its noise.We got two-way phase difference of90degrees and zero as the center of the cosinesignal by used signal conditioning circuit such as integrating filter and differentialamplifier circuit. The signal provided a basis for subsequent further processing.FPGA technology and Mealy type state machine method had been used to achievethe eight segments and distinguish of the grating Moore fringe signals, andachieved the count signal and direction signal output. In this paper, we designed areversible counter to take an improved counting method. It can avoid the impact oncount value from peak interference pulse and improved the accuracy ofsegmentation and counting. This grating methods and results of the eight segmentscan be used as a basis of the breakdown of higher multiples grating.