Scanning display apparatus
US4127850A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 14, 1977 |
| Grant date | Nov 28, 1978 |
| Priority date | — |
| Expiry date | Feb 14, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/42
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A head-up display involving display of pitch-bar symbols in the line of sight of an aircraft pilot is generated using raster scanning of a cathode-ray-tube screen and bright-up in accordance with stored information relating to the wings-level or other datum attitude of the aircraft. Variation of the pitch-bar mapping in the display area to follow change of attitude of the aircraft is made through transformation in accordance with pitch and bank angles applied to the point-by-point progression of the raster scan, and the visual staircase effect of symbols inclined to the line-scan is reduced by controlled variation in brightness from point to point. Each point (x.sub.d, y.sub.d) in the progression of the scan through the display area is mapped back incrementally into the corresponding point (x.sub.p, y.sub.p) of the stored datum-attitude map, through a transformation in rotation dependent on the bank angle .phi.. Computation of x.sub.p involves summation of discrete signals representative of x.sub.d cos.phi. and y.sub.d sin.phi., and of y.sub.p involves summation of discrete signals representative of -x.sub.d sin.phi. and y.sub.d cos.phi.. The eight most-significant bits of the elev…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.