Temperature responsive device
US4279152A · kind A · utility
42Cited by
10References
8Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Feb 22, 1979 |
| Grant date | Jul 21, 1981 |
| Priority date | — |
| Expiry date | Feb 22, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S252/962
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A liquid crystal temperature indicator that gives a visual indication of whether the device is at a temperature above or below one or more threshold values has a homeotropically aligned nematic or smectic layer incorporating a pleochroic dye. The color of the cell changes as the dye will only absorb normally incident light when the temperature causes the liquid to go isotropic. Electrodes may be provided to provide electronic detection of the passage of the liquid through the threshold temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.