Optical change-over switch utilizing ferroelectric liquid crystal material
US4836657A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 1986 |
| Grant date | Jun 6, 1989 |
| Priority date | — |
| Expiry date | Dec 10, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/141
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The liquid crystal cell (30) for the optical change-over switch comprises a pair of transparent substrates (1), a pair of transparent flat electrodes (2) provided on the respective opposing surfaces of the substrates, orientation control films (3) provided on the flat electrodes (2), two pair of comb shaped electrodes (33) respectively provided on the orientation control films (3), and a ferroelectric liquid crystal layer (4) confined between the substrates (1). The optical incidence plane (31) to the cell (30) is so selected that the plane (31) is away from the helical axes (9) of the ferroelectric liquid crystal in the cell (30) in the order of somewhat greater than the tilt angle (.theta..sub.t) of the ferroelectric liquid crystal. The pair of flat electrodes (2) generate a first electric field (37a) perpendicular to the layer (32) and orient the long axes of the ferroelectric liquid crystal molecules into a first orientation (35a') parallel to the layer (32 ) to induce a first refractive index which causes simultaneous reflection of unpolarized light beam (7+8) with a predetermined incidence angle (.theta.). The two pair of comb shaped electrodes (33) generate a second electric…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.