Curve-generating device for visual display of symbols on a cathode-ray screen
US4314351A · kind A · utility
9Cited by
5References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 28, 1980 |
| Grant date | Feb 2, 1982 |
| Priority date | — |
| Expiry date | Jan 28, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G1/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The curve-generating device serves in particular to produce signals relating to a circular line from simple algorithms. The device comprises means for computing a parameter .DELTA.L defined by ##EQU1## where U is an elementary vector, .theta. is the angle at the center of a polygon of side U+.DELTA.L circumscribed about the circle R, and processing logic circuits for determining the polar direction P.sub.n of the plotted line according to the relation: ##EQU2## where EQU .DELTA..sub.n-1 =1 in respect of x.sub.n-1 .gtoreq.U and EQU x.sub.n =x.sub.n-1 +.DELTA.L.multidot..DELTA..sub.n-1 -U.multidot..DELTA..sub.n-1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.