APPARATUS AND METHOD FOR MONITORING LED COLOUR MIX

摘要

An LED assembly (50) includes a plurality of LEDs including a first LED (52, 56, 60) of a first colour and a second LED (54, 58, 62) of a second colour. The assembly also includes a driver (53). The driver (53) includes a monitor (55) for monitoring a response of an LED, the absorption spectrum of which at least partially overlaps the emission spectrum of the first LED, and thereby obtaining an indication of the light output of the first LED. The assembly also includes a current supply (57). The driver (53) is configured to control the current supply to supply current to at least one LED of the plurality of LEDs in dependence upon the indication of the light output of the first LED whereby to maintain a desired colour mix of output light from the LED assembly (50).

主权项

1. A method of controlling the colour mix of output light from an LED assembly including a plurality of LEDs, wherein the LED assembly includes a first LED of a first colour and a second LED of a second colour; the method including:
illuminating an LED with light emitted from the first LED, wherein the absorption spectrum of the illuminated LED at least partially overlaps the emission spectrum of the first LED; determining a response of the illuminated LED to the absorption of light and thereby obtaining an indication of the light output of the first LED; and controlling a current supply to at least one LED of the plurality of LEDs in dependence upon the indication of the light output of the first LED whereby to maintain a desired colour mix of output light from the LED assembly.