A laser ranging system has been developed in which an image converter tube equipped with deflection plates is used to make a precise measurement of the fractional amount by which the time of flight of the ranging pulse exceeds an integral multiple N of the period of a stable oscillator. The value of N is determined in an auxiliary measurement. In short-range tests with a laboratory breadboard version of the system, time-of-flight uncertainties of about 45 psec were observed. The corresponding uncertainty in a range measurement is smaller than 7 mm.
K. E. Golden, D. E. Kind, S. L. Leonard, and R. C. Ward, "Laser Ranging System with 1-cm Resolution," Appl. Opt. 12, 1447-1453 (1973)