Liquid crystal welding glass shields having improved optical angular properties
US5825441A · kind A · utility
Inventors
Key dates
| Filing date | Dec 22, 1995 |
| Grant date | Oct 20, 1998 |
| Priority date | — |
| Expiry date | Dec 22, 2015 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F9/067
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A liquid crystal welding glass structure whose density increases when welding is commenced includes two liquid crystal cells which are mounted between polarization filters which have an extinguishing effect on one another. When mounting the filters, the filters are turned so that their respective angular dependencies on the optical density counteract one another. With the intention of improving this compensating effect, the brushing/rubbing of the mutually opposing limiting walls which determine the direction of the molecules is limited to at least one of the component cells whose relative angular displacement differs from 90.degree. and is smaller than or coincident with 85.degree.. The angle is preferably between 20.degree. and 85.degree..
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.