Abstract:

The counter is mainly consisted of the signal reception,signal conditioning,amplification,analogtodigital conversion,signal processing and count showAtmel 89C51 is responsible for signal processingOptical signals from laser is received by the sensor consisted of photodiode array,and the sensors is sensitive to laser band and can inhibit ultraviolet and infrared wavelengths of light effectivelyAmplifier modulation adopts DC analog signal technique which can avoid the electromagnetic interference that most of the isolation amplifier module haveExperimental results show that the counter is operated simply and it can shorten the measurement time and improve the accuracy of the count

Key words: interference fringes;counters;laser;Michelson interferometer