| 摘要 |
<p>793,352. Luminescent screens. THORN ELECTRICAL INDUSTRIES, Ltd., and SYLVANIA-THORN COLOUR TELEVISION LABORATORIES, Ltd. Nov. 8, 1955 [Nov. 12, 1954; April 7, 1955], Nos. 32917/54 and 10350/55. Drawings to Specification. Class 39(1). [Also in Group XL(b)] In a colour television receiver [see Group XL(b)] the incoming signals are applied to a cathode-ray tube so as to produce on the screen a homochrome image, i.e. an image formed by radiation, specifically greenish white or ultraviolet, of substantially homogenous spectral composition arms the image, and radiation from this image is then diverted to a viewing screen comprising photo-luminescent materials selected to fluoresce in different colours, specifically red, green and blue, and arranged in a repeating sequence of parallel strips disposed transverse the line scanning direction. The screen may receive light by projection or may be disposed on the face of the cathode-ray tube, a lenticular screen in register with the strips being incorporated to reduce loss of light and definition. A filter may be placed over the front-face of the screen to prevent ambient light capable of exciting the photo-luminescent material from marking the screen. Specification 793,351 [Group XL(b)] is referred to.</p> |
