Brightness control in an LED display device
US4099171A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 28, 1977 |
| Grant date | Jul 4, 1978 |
| Priority date | — |
| Expiry date | Jan 28, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G3/14
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The brightness of given LED segments of each digit section of an LED display device for providing illuminated displays of selected alphanumeric characters is controlled by controlling the amount of energy provided to each given digit section for illumination of the given LED segments in accordance with the selection of the character to be displayed by the given digit section. For example, when a character having only three illuminated segments, such as a "7" is displayed, less current is provided to the digit section than when a character having six illuminated segments, such as a "0" is displayed, thereby providing an apparent uniform brightness as to both characters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.