Method of, and apparatus for, producing a television picture with a cathode-ray tube and separate light-source

摘要

548,643. Cathode-ray tube television receivers. GES. ZUR FORDERUNG DER FORSCHUNG AUF DEM GEBIETE DER TECKNISCHEN PHYSIC AN DER EIDGENOSSISCHEN TECHNISCHEN HOCHSCHULE. Oct. 29, 1941, No. 13941. Convention date, Nov. 30, 1940. Addition to 543,485. [Classes 39 (i) and 40 (iii)] Relates to cathode-ray tube television receivers in which a fluid screen is locally deformed by the scanning cathode-ray to modulate a light beam throwing the image on a viewing screen as described in the parent Specification. According to the invention, the fluid medium is caused to move continuously or in small steps through the scanning position so as to prevent accumulations of undesired distortion. As shown in Figs. 1 and 2, the fluid medium is on a disc 1, the part 13 of which is subject to the scanning action of the cathode-ray 12. The disc 1 is slowly rotated by a motor 2 through gearing 3. At the same time, the motor drives a roller 5 through gearing 4 and reciprocates a rake 7 to and fro and up and down by means of an eccentric 8. The rotation of the disc 1 in the direction of the arrow brings the fluid layer out of the scanning position, then under a cooling chamber 9; and from there to the roller 5 which ensures a correct level of the medium before it returns to the scanning position 13. Any fluid adhering to the roller 5 is scraped off by a knife 6, and the accumulation 15, Fig. 2, of fluid against the roller is checked and spread by the reciprocating movements of the rake 7. In a modification, the level of the medium is controlled by a fixed blade behind which an inverted trough-like chamber is provided to receive and spread the excess material at the back of the blade. In another modification, the medium is carried by a belt which unwinds from a reel in a vessel containing the medium and is wound up on another reel in another vessel after passing through the scanning position. In another modification, the fluid medium is picked up by a vertical rotating disc, the lower edge of which dips in a vessel containing the fluid. Rollers may be provided to level the layer on one side and to remove the medium from the other side of the disc. In still another modification, the fluid is made to flow in a layer along a fixed wall, the flow being produced by gravity or by pumping.