Method and apparatus for monitoring the condition of LEDs

摘要

The invention relates to a method and apparatus for monitoring the condition of a LED illuminator comprising one or more light emitting diodes. The invention comprises the steps of: controlling the LEDs by means of pulsed current, measuring the light outputs of the LEDs or the LED illuminator by means of one or more light sensors separately during a minimum and maximum level of the pulsed control current. On the basis of the light outputs measured separately during the minimum and maximum levels of the pulsed control current, two separate measurement signals are generated to compare the light output signals corresponding to the minimum and maximum levels with each other and to thereby make conclusions on the operating condition of the LEDs or the LED illuminator. <IMAGE>