Cathode-ray tube picture projection apparatus
US3980405A · kind A · utility
8Cited by
5References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1974 |
| Grant date | Sep 14, 1976 |
| Priority date | — |
| Expiry date | Sep 13, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B31/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
To prevent a picture of cathode-ray tube, which picture is projected through an optical lens system from being imaged with a deformed shape on a flat plane because of the curved phosphor screen of cathode-ray tube, an optical lens system is provided having imaging characteristics such that the central portion of an image formed thereby is convex toward the optical lens system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.