Techniques for lumen maintenance and color shift compensation
US9335210B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 1, 2014 |
| Grant date | May 10, 2016 |
| Priority date | — |
| Expiry date | Sep 30, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2001/1673
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Techniques are disclosed for maintaining consistent lumen output of a lighting assembly over time. By maintaining a consistent lumen output, it is possible to maintain acceptable color stability where color mixing of multiple outputs is used. The lighting assembly may be any lighting configuration that might suffer from lumen depreciation and/or color drift over time, and may include any type(s) of light source(s) that may be monitored and driven accordingly. The lighting assembly, in addition to light source(s), includes a photo detector and a directed light source, such as a laser. The directed light source provides a golden sample for use in calibrating the photo detector, which in turn monitors lumen output of the light source(s). Drive signals are adjusted to account for lumen depreciation of the monitored light source(s).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.