glass guide

glass guide

[¦glas ′gīd]
(graphic arts)
In microfilm photography, a transparent bar of optical glass employed to guide documents through the photographic field.
References in periodicals archive ?
HAT, a recent winner of an Accelerate Manufacturing Award, was approached by Modec for their expertise in aluminium extrusion forming to help them produce a complex 3D shape for the glass guide channel and the division bar.
The glass guide channel appears on the side windows of the windows while the division bar is used to divide the glass on the windscreen.
Now using the highest tech, German-made scanners available, there are no glass guides and the scanner is able to pick up 16,777,216 colors in the spectrum, compared to 256 shades of gray in the scanning of microfilm.