Tunable LED modules based on CSP-COB

Research has indicated the correlation between color of light sources and human circadian cycle. Color tuning to environmental needs has become more and more important in high quality lighting applications. A perfect spectrum of light should exhibit qualities closest to sunlight with high CRI, but is ideally attuned to human sensitivity. A human centric light (HCL) needs to be engineered according to change environment such as multi-use facilities, classrooms, health care, and to create ambience and aesthetics. Tunable LED Modules were developed by combining chip scale packages (CSP) and chip on board (COB) technology. CSPsare integrated on a COB board to achieve high power density and color uniformity, while adding new function of color tunability. The resulting light source can be continuously tuned from bright, cooler colored lighting during the day to dimmer, warmer lighting in the evening, This paper details the design, process, and performance of the LED modules and its application in warm-dimming LED down light and pendant light.