Method and apparatus for generating elliptical images on a raster-type video display
US4388620A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 5, 1981 |
| Grant date | Jun 14, 1983 |
| Priority date | — |
| Expiry date | Jan 5, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/42
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus provides for the generation of a number of elliptical images on a raster scan video display screen by storing information indicative of a predetermined model image, and for each elliptical image to be displayed, storing data indicative of the vertical and horizontal eccentricity of each image, and its display location. During display time, the vertical eccentricity, horizontal eccentricity, and display location binary information for each elliptical is accessed and used to sequentially read selected portions of the model image information to produce therefrom address signals indicative of the location of individual horizontal display elements that make up the desired elliptical image. The address signals are applied to a random access memory to store marker information indicative of the elliptical image at memory locations corresponding to the position on the display screen that the image will take. The random access memory is sequentially scanned in synchronism with the scan of the electron beam used to form the raster, converted to video information and displayed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.