Microfilm analyser using fixed source as analysis beam - has screen forming secondary source and step displacement system

摘要

A first optical system deviates the analysis beam along a line of known length. The point of impact of the analysis beam on a screen constitutes a secondary source which can move along this line. A second optical system assures the transposition and reduction of the line scanned by the secondary source onto a line of the microfilm. A step-by-step displacement system moves the first optical system perpendicular to the line scanned by the secondary source and a photoelectric detector converts the light transmitted by the microfilm into electrical signals.