摘要 |
Light source circuitry comprises a first group of one or more light emitting diodes operable to emit light of a first color, a second group of one or more light emitting diodes operable to emit light of a second color, and a third group of one or more light emitting diodes operable to emit light of a third color, wherein the first, second and third groups of light emitting diodes are arranged such that, when a fixed current arrives at the light source circuitry, the fixed current is shared between the first, second and third groups, and wherein the circuitry is configured such that a proportion of the fixed current that flows through each of the first and second groups is controllable in dependence on a received control signal and such that the remainder of the fixed current flows through the third group. |