Cold-Mirror Lamps for 8mm Projectors

John O. Geissbuhler

Cold mirror coatings have been incorporated into reflector lamps (or use in the home 8mm motion-picture projector. Light output shows little or no loss, whereas the total energy absorbed by the film has been reduced by 50% for some films. Methods for testing these lamps are shown. Problems of coating uniformity, visible light reflectance, infrared transmission, and color bias are discussed.

Print ISSN
Published
1963-09
Content type
Original Research
DOI
10.5594/J07283