CRT picture display apparatus
US4638308A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1984 |
| Grant date | Jan 20, 1987 |
| Priority date | — |
| Expiry date | Sep 26, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K4/026
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A CRT picture display apparatus of the raster scan type comprises a cathode ray tube for raster scanning, a horizontal deflection circuit for supplying a horizontal deflection current to a horizontal deflection coil of the CRT, a vertical deflection circuit for supplying a vertical deflection current to a vertical deflection coil of the CRT, and a display data generator for supplying data to be displayed to the CRT. The horizontal deflection circuit produces as the horizontal deflection current a triangular current having one period which is twice a horizontal scanning period, and the triangular current has a first portion which increases in response to a horizontal sync signal at a predetermined inclination and a second portion which decreases in response to the next horizontal sync signal at the predetermined inclination and continues until the further next horizontal sync signal, whereby the period for a scanning line to proceed from lefthand end to righthand end of a raster on a screen of the CRT is made substantially equal to the period for the next scanning line to proceed from righthand end to lefthand end, and data is displayed during both the periods.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.