Heated ferroelectric liquid crystal spatial light modulator with improved contrast, improved grayscale resolution, and decreased pixel sticking when operated in a non-DC balanced mode
US6157432A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 29, 1999 |
| Grant date | Dec 5, 2000 |
| Priority date | — |
| Expiry date | Jan 29, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2320/041
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A heated ferroelectric liquid crystal-based spatial light modulator (SLM) that minimizes pixel sticking when operated in a non-DC-balanced mode with spiking and method for using same. The SLM comprises a transparent electrode, a pixellated electrode, ferroelectric liquid crystal material, and a heater. The ferroelectric liquid crystal material is sandwiched between the transparent electrode and the pixellated electrode. The heater is capable of heating the ferroelectric material to at least 40.degree. C. and preferably to between 50 and 60.degree. C. The invention may also provide a temperature sensor for detecting the temperature of the SLM and a temperature control circuit that is electrically connected to both the temperature sensor and the heater. The temperature sensor may be a diode located proximate to the pixellated electrode or a photo-diode located remote from the spatial light modulator. The heater may be integrated into and encapsulated by a substrate supporting the pixellated electrode or it may be supported on a second major surface of the substrate. The method according to the invention includes providing a SLM, preheating the SLM, and operating the SLM in a non-DC-b…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.