Self-inspecting convergence measuring apparatus
US5077600A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 1, 1990 |
| Grant date | Dec 31, 1991 |
| Priority date | — |
| Expiry date | Oct 1, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/28
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A convergence measurement apparatus for a color CRT comprising a light sensor which is placed on the face of a CRT to be tested, a CPU, and a pattern generator which causes a plurality of luminescent lines of a primary color to be displayed on one area of the CRT screen and a plane area comprised of a composite of the two other primary colors to be displayed on another area of the screen. The plurality of lines are shifted at a given rate along the designated area of the screen, the color of the displayed lines successively changing to show each primary color. The light sensor receives light intensity information from the generated pattern and the CPU calculates a mis-convergence value based on the light intensity data. The apparatus further includes a self-inspection feature by which the processing is executed for successive measurement of the same primary color. If the values for each measurement are identical the system is assumed to be operating normally and if there is variation, abnormal operation can be diagnosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.