Incandescent bulb luminance matching LED circuit
US5929568A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 8, 1997 |
| Grant date | Jul 27, 1999 |
| Priority date | — |
| Expiry date | Jul 8, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An incandescent bulb luminance matching LED circuit for causing the luminance of an LED to match the luminance of an incandescent bulb is disclosed. The incandescent bulb luminance matching LED circuit includes an input port (26, 56 or 82), an output port (28, 58 or 98), one or more light emitting diodes (22, 24, . . . or 88, 90 . . .), and a voltage (20 or 89) and/or current (50 or 86) compensation block. The compensation block(s) is connected in circuit with the light emitting diode(s) between the input port and the output port and compensates for voltage and/or current changes in the power applied to the input port such that the luminance of the LED is approximately the same as that of an incandescent bulb. In one embodiment, the compensation block comprises a zener diode (30) connected in series with the light emitting diode(s) (22, 24, . . .) between the input port (26) and the output port (28). In an alternate embodiment, the compensation block comprises one or more current diode(s) (60, 62, . . .) connected in parallel with the light emitting diode(s) (52, 54, . . .) between the input port (56) and the output port (58). In yet another embodiment, the compensation block compr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.