Electrooptical filter cartridge and a method for manufacturing the same
US5854667A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 4, 1997 |
| Grant date | Dec 29, 1998 |
| Priority date | — |
| Expiry date | Apr 4, 2017 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F9/023
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
In the invention, an active electrooptical filter cartridge comprises a flat housing (10, 12, 16) forming a closed cavity, which is completely filled with an optical transmissive resin (44, 52, 56, 60, 62) and an active device (14). The active device (14) is completely surrounded and fixed by the resin and comprises as components an LC panel (30, 32) positioned between light-transmissive portions (24, 28) of opposite main walls (10, 16) of the housing, a sensor means (34, 36) for detecting incident light on the filter cartridge, a circuit means (38) for controlling the LC panel (30, 32) in response to an output from the sensor means (34, 36), and a power supply means (40, 42) for operating the active device (14). The filter cartridge can be manufactured with the same dimensions as a passive, darkened filter glass, e.g. for use in welding helmets.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.