Optical scanning apparatus for photolithography of a color cathode ray tube having an aperture mask
US4053905A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 23, 1976 |
| Grant date | Oct 11, 1977 |
| Priority date | — |
| Expiry date | Jun 23, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J9/2272
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In an optical scanning apparatus for photolithographic processing of faceplates intended for color cathode ray tubes, a light beam from a source is first deflected through an angle related to a predetermined angle of incidence that an electron beam in an operating tube has with respect to a defined faceplate location, and then the deflection point is imaged onto or in the vicinity of the faceplate. This angle of incidence adjustment is accomplished for each faceplate location as the light beam is scanned over the surface of the faceplate. The light source, which is preferably a laser light source, creates a light beam having a wavelength spectrum which exposes the photosensitive material. The beam is deflected by a pair of orthogonally aligned mirrors which are rotated by galvanometers. Each galvanometer is driven by a current from an electrical control, the current being related to the proper angle of incidence for each faceplate location. An optical focusing device images the point of deflection of the light beam substantially onto the faceplate. This image of the deflection source is then scanned over the surface of the faceplate in a predetermined pattern by a mirror which is r…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.