Automatically controlling illuminating light color in the presence of ambient light

Nowadays, multi-color LEDs are widely used in our daily life. One popular application is adjusting LED light color according to different scenes, e.g. to enhance visual effect. However, there is inevitably other light from surrounding environment, e.g. daylight. If the LED light color is rendered without considering the influence of ambient light, the resulted light color can differ from the desired one. To tackle this issue, this paper presents an innovative way to achieve the desired color, by eliminating the influence of the ambient light. To this end, we first measure the chromaticity and the illuminance of the ambient light at a target point. Then we tune the color of the LED light in such a way that the mixture of the two light sources renders the desired color. Simulation studies will verify the effectiveness of the proposed method.