Battery Powered Light Source for Compartment Illumination

摘要

A battery powered LED light source is described for illuminating the inside of a dark enclosure when the enclosure is opened in an environment with ambient illumination. Drive circuitry adapted to the LED light source turns on the LEDs when levels of ambient light above a threshold are detected, which may occur if the light source is placed in a dark enclosure that is opened in a lit room. After being opened, the drive circuitry periodically strobes off the LED light source to take ambient light measurements without the contribution of its own LED light for determining if the enclosure has been closed and the LED light source should again be shut off.

主权项

1. A light source comprising:
a light emitting diode LED; an ambient light detector detecting an illumination in a volume proximate the LED; and a controller receiving an output from the ambient light detector and automatically turning on power to the LED when the output from the ambient light detector indicates a first change in the illumination above a first threshold, the controller also interrupting power to the LED for a predetermined period to allow the ambient light detector to detect a second change in the illumination level below a second threshold.