Abstract: 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.

Abstract: In a projection type television apparatus, a first and a second color selecting device are located on an optical light path passing through a cathode ray tube and a series of projection lenses are disposed in front of the cathode ray tube without a color selecting device therein. The first color selecting device has a high refractive factor to light having a wavelength of 570nm or more and the second color selecting device has a high reflection factor or a high absorption factor to light having a wavelength of 520nm or less. With this color selecting device, the range of color reproduction can be much more improved. This thus causes an increased degree of color purity of green light at the central and peripheral areas of the cathode ray tube. Moreover, with this arrangement, it becomes easy to conserve the characteristic of the color selecting devices and to facilitate the manufacturing operation.

Abstract: In a projection television apparatus, a color selecting device is located on an optical light path passing through a cathode ray tube and a series of projection lenses disposed in front of the cathode ray tube. This color selecting device has a high reflection factor or a high absorption factor to light having a wavelength of at most 520 nm. With this color selecting device, the range of color reproduction can be much more improved, thus causing an increased degree of color purity of green at the central and peripheral areas of the cathode ray tube.