High resolution continuously distributed silicon photodiode substrate
US4198647A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 17, 1979 |
| Grant date | Apr 15, 1980 |
| Priority date | — |
| Expiry date | Jan 17, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/1354
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
This invention is directed to a semiconductor structure that includes at least one wafer that is fully depleted of all mobile carriers and is used as a medium for the movement of spatially modulated signal represented by charge carriers through the wafer with a spatial resolution that is smaller than the thickness of the wafer. This may be used in the form of a continuous high resolution silicon photodiode substrate to serve as an image input means for an electro-optical display medium, such as a liquid crystal. Next to the photoactivated substrate is a liquid crystal and next to the crystal is a transparent electrode. The photodiode is reverse biased and both of its sides are depleted of all mobile charges throughout its entire thickness. Thus, charges generated in the substrate move to the display not by diffusion as in prior art devices (e.g. the solid state silicon vidicon) but by the influence of the electric field which tends to minimize their lateral spread and thereby achieves a high spatial resolution in spite of the continuous character of this silicon diode device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.