Illumination and light gate utilization methods and apparatus
US4316196A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 27, 1979 |
| Grant date | Feb 16, 1982 |
| Priority date | — |
| Expiry date | Mar 27, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/055
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Methods and apparatus for recording varying electric signals with a plurality of electrically actuable light gates illuminate the light gates with light of a first intensity above zero light intensity and provide a light-sensitive recording medium sensitive to illumination levels at light intensities including the mentioned first light intensity and starting at a second light intensity below such first intensity and above zero light intensity. These methods and apparatus precondition the light gates to subsequent opening in response to varying electric signals by electrically biasing the light gates to an initially open condition wherein the gates pass light from the mentioned illumination at an intensity below the second light intensity. The recording medium is thus exposed to light passed by the preconditioned gates at below the second intensity. Thereafter, the preconditioned light gates are selectively energized and further opened in response to varying electric signals to pass light at at least the second light intensity for a recording of such electric signals on the recording medium. The same principle may be employed for reading information with the aid of electrically cont…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.