Method and device for controlling voltage provided to a suspended particle device
US6804040B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 2003 |
| Grant date | Oct 12, 2004 |
| Priority date | — |
| Expiry date | Feb 13, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B26/004
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A voltage controlling device includes an AC terminal receiving an AC voltage signal, a voltage dividing device adapted to divide the AC voltage signal into a plurality of distinct voltage signals within a predetermined range, a controller adapted to control the voltage dividing device to provide a selected voltage level based on voltage level information and an SPD terminal for providing the selected voltage level to a suspended particle device. Voltage level information may be provided via an input device and/or from a photocell that monitors a light level at the suspended particle device. A separate AC power supply may also be provided. The controller may also monitor an SPD load voltage to control the voltage level provided to the SPD terminal in order to prevent shocking of a user.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.