Accurate control of chromaticity and spectra by feedback phosphor-coating

Accurate control of chromaticity and spectra by feedback phosphor-coating

2015/4 Mei-Tan Wang and Jung-Min Huang

Abstract: The chromaticity coordinates and spectra of phosphor-converted LEDs are demonstrated to be well controlled in this study. Through the feedback coating method of stacked yellow, green, and red phosphor layers, the color rendering index (CRI), correlated color temperature (CCT), and spectra are determined to match precisely the desired target. In addition, the reabsorption effect is strongly influenced by the order of stacked phosphor layers and the selected excitation wavelength of phosphors. The degree of reabsorption will modify the original spectra and cause a mismatch between the experimental measurement and the simulation based on the linear superposition of blue light and phosphor-emitted light. This feedback coating method offers an easy approach towards optimized spectra, which can offer the highest luminous efficacy of radiation with excellent colorrendering properties.

•  Link:

http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-23-9-11576

• International Journals (國際期刊):

Mei-Tan Wang and Jung-Min Huang , Accurate control of chromaticity and spectra by feedback phosphor-coating, Optics Express, Vol. 23, Issue 9, pp. 11576-11585 (2015)

• download:

https://drive.google.com/file/d/0B-Jg2ZDReoWubWtEOGF0R3hXSk0/view?usp=sharing