摘要 |
A projection television apparatus is composed of a combination of cathode ray tubes for the three primary colors, red, green and blue. The green and blue cathode ray tubes have a multilayered interference filter disposed on the inner surface thereof and display light on a screen, the intensity of which is varied by the multilayered interference filter, passing through a series of projection lenses positioned in front of the cathode ray tubes. The red cathode ray tube has no multilayered interference filter and produces light having a distribution of luminous intensity nearly equal to that of the green and blue lights. This is achieved by displaying light, the luminous intensity of which is not varied, passing through a series of projection lenses with a diaphragm.
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