Abstract A cathode-ray tube for a color television receiver having an evacuated glass envelope which includes a faceplate panel, a funnel portion and a neck portion. The faceplate panel has a plurality of different color light-emitting phosphors thereon. A control electrode is positioned immediately adjacent the faceplate panel to assist in the excitation of the phosphor elements by appropriate electron beams. The control electrode takes the form of a shadow mask, and the phosphor elements are triads of blue, red and green light emitting phosphor dots. The shadow mask is supported at the inside of the faceplate panel by three springs which are mounted on bimetal ''''hinges'''' for adjustably positioning the shadow mask as temperature within the tube envelope changes. For instance, increases in temperature within the envelope tend to spread the openings in the shadow mask, and this is compensated by the effect of the bimetallic hinges which move the shadow mask in the direction of the faceplate panel. The tube envelope is coated with a vacuumdeposited aluminum layer which serves to prevent the buildup of high-voltage charges on the wall of the tube. Strips of a conductive colloidal graphite solution may be applied between certain critical points of electrical contact inside the tube envelope.
A color television cathode-ray tube having a screen portion of a plurality of different color light-emitTing phosphor elements and a shadow mask disposed adjacent thereto for selectably guiding an electron beam onto said light-emitting phosphors, said cathode-ray tube having a funnel portion, a thin metallic film deposited on the inner surface of said funnel portion, a high-voltage connection to said metallic film and electrical contacting means extending from said shadow mask to the metallic film for providing a high voltage connected to said shadow mask and the metallic film from said high-voltage connection.
Claim 2
Dependent Claim
93 words
A color television cathode-ray tube having a screen portion of a plurality of different color light-emitTing phosphor elements and a shadow mask disposed adjacent thereto for selectably guiding an electron beam onto said light-emitting phosphors, said cathode-ray tube having a funnel portion, a thin metallic film deposited on the inner surface of said funnel portion, a high-voltage connection to said metallic film and electrical contacting means extending from said shadow mask to the metallic film for providing a high voltage connected to said shadow mask and the metallic film from said high-voltage connection.
Claim 3
Dependent Claim
30 words
A color television cathode-ray tube in accordance with claim 1 wherein an additional conducting layer is deposited in a continuous area from the high-voltage connection to said electrical contacting means.
Claim 4
Dependent Claim
27 words
A color television cathode-ray tube in accordance with claim 1 wherein said metallic coating is an aluminum layer deposited on the inner surface of said funnel portion.
Claim 5
Dependent Claim
34 words
A color television cathode-ray tube in accordance with claim 2 wherein said additional conducting layer comprises a layer of colloidal graphite solution for increasing the conductivity between said high-voltage connection and said shadow mask.
Claim 6
Dependent Claim
36 words
A cathode-ray tube in accordance with claim 1 wherein a bimetallic element is provided to automatically compensate for the position of said shadow mask with changes in temperature within said envelope due to heating effects therein.