Development of photoelectric pulse laser range finding system

The important development trend of laser pulse range finding system is to improve precision and realize miniaturization. This thesis researches laser pulse range finding system and analyses the key technique on the working principle and the time measurement accuracy. Based on the analyses and compared with several existent timing methods, the method of combining traditional counting method with time linear stretching technique is choosen to achieve high precision measurement of interval. Time linear stretching technique can realize a high measurement precision at low frequency so as to decrease the difficulty of design and the cost of circuit. On laser shooting aspect, laser diode with a small volume and a low weight which can meet the requirement for the medium-short distance measurement and the driving chips with high performance are used to generate good light pulses with steep, steady and narrow bandwidth. Also the light pulses should have adequate power, or they may be submerged by noise, so the echo pulses can't be received. On the aspect of signal receiving, the avalanche photodiode which has high respond degree to some special wavelength and low noise is used as receiving device utilizing a high bandwidth enlarging chip and a high speed comparison to pick-up useful signals.