3920951 is referenced by 21 patents and cites 11 patents.

An improved laser etching apparatus for forming a photographic image on a metallic or non-metallic surface is described. The apparatus comprises a variable rate, 'Q' switched laser, whose beam is focused on one element of a blank at a time. The laser is controlled by means of an apertured photodetector which senses the brightness of an element on a photographic transparency and produces an electrical signal corresponding to the brightness of that element. The electrical signal controls the rate at which the laser produces pulses. The blank is scanned in respect to the etching laser beam simultaneously with the transparency being scanned in respect to the apertured photodetector. The picture produced on the blank contains an assemblage of laser etched craters. In dark regions of the picture, the craters occur in greater densities while in light regions of the picture, the craters occur in lesser densities. The overall appearance of the laser etched image is that of a half-tone print reproducing the transparency.

Title
Laser etching apparatus for forming photographic images on metallic surfaces
Application Number
05/475,419
Publication Number
3920951
Application Date
June 3, 1974
Publication Date
November 18, 1975
Inventor
Manoni Albert J
Chovan Joseph L
Agent
Neuhauser Frank L
Baker Carl W
Lang Richard V
Assignee
General Electric Company
IPC
B23K 27/00
B23K 26/08
B44B 07/00
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