Liquid crystal display device including multiple ambient light illumination modes with switchable holographic optical element
US5745203A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1996 |
| Grant date | Apr 28, 1998 |
| Priority date | — |
| Expiry date | Mar 28, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/32
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A liquid crystal display device (10) for forming a display includes a liquid crystal panel (12), a switchable holographic optical element (14), and a reflective holographic optical element (16). Ambient light illuminates a front polarizer (18), which polarizes the ambient light and transmits the polarized light to the liquid crystal cell (20). The liquid crystal cell (20) receives the polarized light and transmits polarized light derived from the incident polarized light to a back polarizer (22). The back polarizer (22) polarizes the light and transmits the light to the switchable holographic optical element (14). While in a first mode, the switchable holographic optical element (14) redirects the light back toward the liquid crystal panel (12) within a first viewing cone (34) to form the display. In a second mode, the switchable holographic optical element (14) is transparent and transmits the light to the reflective holographic optical element (16). The reflective holographic optical element (16) redirects the light back toward the liquid crystal panel (12) in a second viewing cone (36) to form the display. The second viewing cone (36) is preferably narrower than the first viewin…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.