Lighting device with color control, and method of lighting
View Patent ↗A lighting device comprising a group of one of more illumination solid state light emitters, a reference solid state light emitter and a reference sensor which detects an intensity of the reference solid state light emitter. Each of the emitters (1) has an illumination which is spaced from a first point by a delta u′, v′ distance on a 1976 CIR diagram of not more than 0.015, and/or (2) has a forward voltage temperature dependence which is within 5% of a first forward voltage temperature dependence. In addition, a lighting device comprising one or more illumination solid state light emitters, a reference solid state light emitter and a sensor which comprises at least two areas of individual sensors. Also, methods of lighting.
1. A lighting device comprising:
a first group of solid state light emitters, said first group of solid state light emitters comprising at least one solid state light emitter, said first group of solid state light emitters (1) having an illumination which corresponds to a point on a 1976 CIE diagram which is spaced from a first group point by a distance such that delta u′, v′ relative to the first group point is not more than 0.015 on said 1976 CIE diagram, and/or (2) having a forward voltage temperature dependence which is within 5% of a first group forward voltage temperature dependence;
at least one first group reference solid state light emitter, said first group reference solid state light emitter (1) having an illumination which corresponds to a point on said 1976 CIE diagram which is spaced from said first group point by a distance such that delta u′, v′ relative to said first group point is not more than 0.015 on said 1976 CIE diagram, and/or (2) having a forward voltage temperature dependence which is within 5% of said first group forward voltage temperature dependence; and
a first reference sensor which detects an intensity of said first group reference solid state light emitter.
2. A device as recited in claim 1 , further comprising at least one other light emitter.
3. A method of lighting, comprising:
supplying current of a first magnitude to a first group of solid state light emitters, said first group of solid state light emitters comprising at least one solid state light emitter, each of said first group of solid state light emitters (1) having an illumination which corresponds to a point on a 1976 CIE diagram which is spaced from a first group point by a distance such that delta u′, v′ relative to the first group point is not more than 0.015 on said 1976 CIE diagram, and/or (2) having a forward voltage temperature dependence which is within 5% of a first group forward voltage temperature dependence;
supplying current of substantially said first magnitude to a first group reference solid state light emitter, said first group reference solid state light emitter (1) having an illumination which corresponds to a point on said 1976 CIE diagram which is spaced from said first group point by a distance such that delta u′, v′ relative to said first group point is not more than 0.015 on said 1976 CIE diagram, and/or (2) having a forward voltage temperature dependence which is within 5% of said first group forward voltage temperature dependence; and
detecting an intensity of light from said first group reference solid state light emitter.
4. A method as recited in claim 3 , further comprising adjusting current supplied to said first group of solid state light emitters and to said first group reference solid state light emitter to a second magnitude.
5. A method as recited in claim 4 , further comprising sensing said second magnitude.
6. A method as recited in claim 3 , further comprising supplying current of a second magnitude to a second group of solid state light emitters, said second group of solid state light emitters comprising at least one solid state light emitter, each of said second group of solid state light emitters (1) having an illumination which corresponds to a point on said 1976 CIE diagram which is spaced from a second group point by a distance such that delta u′, v′ relative to said second group point is not more than 0.015 on said 1976 CIE diagram, and/or (2) having a forward voltage temperature dependence which is within 5% of a second group forward voltage temperature dependence;
supplying current of substantially said second magnitude to a second group reference solid state light emitter, said second group reference solid state light emitter (1) having an illumination which corresponds to a point on said 1976 CIE diagram which is spaced from said second group point by a distance such that delta u′, v′ relative to said second group point is not more than 0.015 on said 1976 CIE diagram, and/or (2) having a forward voltage temperature dependence which is within 5% of said second group forward voltage temperature dependence.
7. A method as recited in claim 3 , further comprising reducing an intensity of UV light reaching a first reference sensor from said first group reference solid state light emitter.