Abstract For cooling the faceplate of a high-energy cathode ray tube in an in-line television projection system, a cooling cell (5) constructed as a separate entity is interposed between the CRT faceplate (2) and the transmission lens (3) which is arranged in front of and in line with the cathode ray (1). The cooling cell comprises two flexible transparent diaphragms (6 and 7) which are conected at their peripheries to form an enclosure (8) for containing a cooling liquid and which are arranged in contact with the front surface 2a of the CRT faceplate and the rear surface (4) of the lens. The cooling cell has an inlet (11) and an outlet (12) through which circulating liquid enters and leaves the cell.
Inventors
👤 Harry Howden
Bibliographic Details
Application Number—
JurisdictionEP
Data Sourcegoogle_patents
Last Synchronized2026-11-08 06:55
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/006
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
94 words
A means for cooling the faceplate of the cathode ray tube in a television projection system of the kind described, said means comprising a cooling cell which is constructed to be interposed between the front surface of the faceplate of the cathode ray tube and the rear surface of the transmission lens and which comprises two flexible transparent diaphragms connected at their peripheries to form an enclosure for containing a cooling liquid, an inlet and an outlet being provided at the periphery of the enclosure through which liquid can enter and leave the enclosure.
Claim 2
Dependent Claim
94 words
A means for cooling the faceplate of the cathode ray tube in a television projection system of the kind described, said means comprising a cooling cell which is constructed to be interposed between the front surface of the faceplate of the cathode ray tube and the rear surface of the transmission lens and which comprises two flexible transparent diaphragms connected at their peripheries to form an enclosure for containing a cooling liquid, an inlet and an outlet being provided at the periphery of the enclosure through which liquid can enter and leave the enclosure.
Claim 3
Dependent Claim
37 words
A cooling means as claimed in Claim 1, wherein the inlet and outlet each comprise a chamber formed with an inlet port and an outlet port respectively and having open communication with the interior of said enclosure.
Claim 4
Dependent Claim
38 words
A cooling means as claimed in Claim 1 or 2, wherein the diaphragms are made of a transparent plastics material having a refractive index which matches that of the material of the faceplate of the cathode ray tube.
Claim 5
Dependent Claim
61 words
A television projection system of the kind described comprising a cooling means as claimed in Claim 1, 2 or 3, the cooling cell being interposed between the cathode ray tube and the transmission lens with the outer surfaces of the diaphragms in contact with the front surface of the faceplate of the tube and the rear surface of the lens respectively.
Claim 6
Dependent Claim
58 words
A television projection system as claimed in Claim 4, wherein the inlet and outlet of the cooling cell are connected to a heat-dissipating device which forms with the cooling cell a closed circulating system, the system containing a cooling liquid having a refractive index which matches that of the material of the faceplate of the cathode ray tube.