TM 5-6675-316-14
(20) The parallel light from the COillimator lens passes along the optical
plane into the collector lens. This lens has a focal length distance of 350 mm,
which is the optical distance between this lens and the film plane. The image is
turned through 90 degrees by the 45-degree angle mirror and onto the film plane.
The collector lens is mounted on a carriage parallel to the film plane. This
carriage moves along wayrods driven by a stepping motor/cable arrangement.
(Absolute Character Width) X (Point Size)
Number of Motor Steps =
3
(21) The horizontal distance that the scanning carriage will move is deter-
mined by the main program using the formula above. In this manner, correct spacing
for specific character width is maintained. (Character width is obtained from the
disc track for each character.)
b. Film feed and magazine system.
(1) Vertical spacing between lines of exposed copy is accomplished by
advancing the exposed film upward as each line of type is exposed. The unexposed
film is stored in a lightproof container in the film feed magazine. Film is pulled
from the storage container by the pressure rollers. The stepping motor is gear-
coupled to the pressure rollers, which drives the film past the cutter and into the
take-up cassette.
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