System and method for determining light source current
US7308375B2 · kind B2 · utility
35Cited by
16References
20Claims
0Family size
Inventors
Key dates
| Filing date | May 14, 2001 |
| Grant date | Dec 11, 2007 |
| Priority date | — |
| Expiry date | Oct 14, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/193
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system and method are provided for determining a light output of a light emitting diode (LED) in a scanner. The system includes a processor circuit to execute current control logic to obtain an optimum light output from the LED. The current control logic repeatedly applies increasing or decreasing currents to the LED until a saturation point is identified. This may be accomplished, for example, by comparing two measures of the light output of the LED for two different currents applied to the LED. When a difference equaling a predetermined threshold between the two measures is detected, then the saturation point is identified.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.