Article of manufacture for projection television system

• US 4,393,329 A
• Filed: 05/29/1980
• Issued: 07/12/1983
• Est. Priority Date: 01/08/1980
• Status: Expired due to Term

• Current Assignee: Zenith Radio Corporation
• Original Assignee: Zenith Radio Corporation
• Inventors: Lehnert, Stanley E.
• Primary Examiner(s): LAROCHE, EUGENE
• Application Number:
  US06/154,197
• Time in Patent Office: 1,139 Days
• Field of Search: 220/2.1 A, 313/474, 313/477, 313/478, 313/416, 313/461, 313/482, 313/415, 313/364, 313/398
• US Class Current: 313/477.00R
• CPC Class Codes: H01J 29/861 Vessels or containers characterised by the form or the structure thereof
• CPC Class Codes: H04N 9/28 Arrangements for convergence or focusing
• CPC Class Codes: H04N 9/31 Projection devices for colour picture display , e.g. using electronic spatial light modulators [ESLM]

Abstract

An article of manufacture is disclosed for use in a projection television system. A cathode ray picture tube has a face panel with a rearwardly extending skirt and a window for receiving a cathodoluminescent imaging screen. The tube has a seal land which defines a plane whose normal makes a non-zero acute angle with respect to the axis of said window. The article is for use in a system having a cathode ray picture tube whose projection optical axis is on the axis of a remotely located viewing screen, and at least one displaced axis cathode ray picture tube; that is, a tube whose projection optical axis is displaced from the axis of the viewing screen by a non-zero acute angle.

Claims

1. For use in a projection television system, an article of manufacture comprising a cathode ray picture tube having a face panel with a rearwardly extending skirt and a window for receiving a cathodoluminescent imaging screen, said tube having a seal land which defines a plane whose normal makes a non-zero acute angle with respect to the axis of said window.

2. The cathode ray tube defined by claim 1 wherein said face panel is circular.

3. The cathode ray tube defined by claim 1 wherein said face panel is a rectangle.

4. For use in a projection television system, an article of manufacture comprising a glass cathode ray picture tube having a face panel with a rearwardly extending skirt and a window for receiving a cathodoluminescent imaging screen, the edge of said skirt defining a plane whose normal makes a non-zero, acute angle with respect to the axis of said screen.

5. For use in a projection television system, an article of manufacture comprising a cathode ray picture tube having a face panel with a rearwardly extending skirt and a window for receiving a cathodoluminescent imaging screen, said panel skirt being conjoinable with a funnel by mating along interfacing edges, with the edge of said skirt defining a plane whose normal makes a non-zero acute cant angle with respect to the axis of said window said funnel edge defining a plane whose normal makes a non-zero acute cant angle with respect to the funnel axis, whereby said funnel can be aligned and conjoined with said face panel to define a selected tilt angle with respect to the axis of said window.

6. The article of manufacture defined by claim 5 wherein the angle defined by said skirt edge is substantially equal to the angle defined by said funnel edge.

7. The article of manufacture defined by claim 5 wherein each cant angle is approximately equal to one-half of said tilt angle.

8. For use in a projection television system, a cathode ray picture tube whose projection optical axis is displaced from the axis of a remotely located viewing screen by a non-zero acute angle A, and with a cathodoluminescent imaging screen whose axis is substantially coincident with said projection optical axis and normally coincident with the electron-optical axis of said tube, said imaging screen providing an electron-formed visible image for projection on said viewing screen, said cathode ray picture tube having a conjoinable face panel with a rearwardly extending skirt and a funnel which mate along interfacing seal edges, said funnel seal edge being formed to define a plane whose normal makes an angle with respect to the funnel axis substantially equal to one-half said angle A, and with said face panel seal edge formed to define a plane whose normal makes an angle with respect to the imaging screen axis substantially equal to one-half said angle A, said funnel being aligned with respect to said face panel to tilt said electron-optical axis with respect to said projection optical axis by an angle B substantially equal to said angle A, such that when said seal edges are conjoined, the value of said angle B and the orientation of said electron-optical axis causes said electron-formed visible image to have an orientation oand non-linear magnification distortion effective to substantially compensate for the off-axis-induced, non-linear magnification distortion of the light image projected thereby on said viewing screen.

9. The cathode ray tube defined by claim 8 wherein said face panel is circular.

10. The cathode ray tube defined by claim 8 wherein said face panel is rectangular.