Interferometer-less coherent optical range finder

A new coherent optical detection technique employing coherent frequency-dom ain reflectometry and a novel optical frequency sensor is demonstrated for high-precision optical path-length measurements. Using pulsed laser sources , an improvement of more than two orders of magnitude in spatial resolution over conventional optical coherent frequency domain reflectometry techniqu es is demonstrated. Varying degrees of spatial resolution ranging from seve ral centimeters to a few hundred nanometers are achieved, High-precision di stance measurement with long baseline is also presented.