Patent ID: 7193692
Filing Date: 2007-03-20
Classification: G01S

Abstract:
1. A laser range finder, comprising: a transmitter for transmitting a laser signal toward a target, a reflected signal being reflected from said target; a receiver for receiving said reflected signal, wherein a real fly time is defined as an elapsed time from a first time point as said transmitter transmits said laser signal to a second time point as said receiver receives said reflected signal; a time-counting module, coupled to said transmitter and said receiver, for measuring said real fly time to obtain a measured fly time, said time-counting module generating a plurality of timing units, each timing unit corresponding to one measurement resolution, said plurality of timing units comprising a first timing unit and a second timing unit, said second timing unit being longer than said first timing unit; and a processor, coupled to said time-counting module, for generating a distance value based on said measured fly time; wherein said time-counting module obtains a first measured value, M, by using said first timing unit, said time-counting module obtains a second measured value, N, by using said second timing unit, both M and N are positive integers; wherein, if N is equal to M, N times of said second timing unit is used as said measured fly time.