Research On Phase Type Semiconductor Laser Rangefinders

Laser range finder is kind of instrument used by lasers for distance determination. During work laser range finder emits a beam of collimated light to target and photosensitive sensor receiving target diffused reflection, calculate the time that collimated light from transmitter to a receiver, and thus calculate the distance from the observer to the target.This paper mainly researched on phase-shift laser measurement of basic principles, it also compares with several other laser ranging methods. This paper designed by phase semiconductor laser range-finders mainly into four sections:emit part, receiving part,digital signal processing part and optical path part.Emit part design was used in directly modulated semiconductor laser diode as the optical source and the optical source drive circuit design, receiving part was used silicon photo detective as acceptance device,also research and design magnified filter circuit,digital signal processing measure phase by use the high speed FPGA to process the pulse time interval which voltage controlled oscillator produced,to enhance the accuracy measurement of the laser range apparatus.