Patent ID: 6246469
Filing Date: 2001-06-12
Classification: G01B,G01D,G01K,G01L,G01S,G06F

Abstract:
A system for measuring a distance to a remote object comprising:a source for transmitting an optical measurement signal beam to the object;a detector for generating an output signal in response to detection of a reflection of said signal beam from the object, said detector output signal being related to an amplitude of said detected reflection;an element responsive to the detector output signal for causing said source to continually transmit the measurement signal beam at a first amplitude while said reflection is detected as being at a second amplitude, and for causing said source to continually transmit the measurement signal beam of said second amplitude while said reflection is detected as being at said first amplitude, whereby said signal beam is an analog signal that is continuously transmitted and amplitude modulated; andmeasurement means for measuring a frequency of modulation of said signal beam, said frequency being indicative of a distance from said source to the object.