A process for producing calibration markers directly on the photoconductive surface of video camera tubes has been developed. This process includes the use of a Nd:YAG laser operating at 1.06 µm with a 9.5-nsec pulse width (full width at half-maximum). The laser was constrained to operate in the TEM00 spatial mode by intercavity aperturing. The use of this technology has produced an increase of up to 50 times the accuracy of geometric measurement. This is accomplished by a decrease in geometric distortion and an increase in geometric scaling. The process by which these laser-formed video calibrations are made will be discussed.
J. B. Franck, P. N. Keller, R. A. Swing, and G. G. Silberberg, "Process for producing laser-formed video calibration markers," Appl. Opt. 22, 2481-2483 (1983)