Study on colorimetric properties of LED array sources for color vision application

Abstract

Color vision is based on a three-color colorimeter of colorimetric principle, and the colorimetric properties of illumination is the key factor for color imaging. Therefore based on the principle of colorimetry, in this paper we analyse and calculate the colorimetric properties of LED array sources for color vision application. By comparison with the standard D65 light source, the adjustment principle and range of correlated color temperature are studied for LED array sources. Chromaticity coordinates and relevant color temperature of white balance are also studied. The LED array source has a large range for adjusting the correlated color temperature and has a better ability of color display. Chromaticity coordinates and relevant color temperature of white balance R:G:B=254:237:90 are closer to those of the standard chromaticity. The ability of color reproduction reaches a better result of color reproduction. Therefore, the colorimetric properties of LED array sources are more appropriate for color vision application.

Mini-review of rare charmonium decays at BESIII

“…By using unitarity considerations, limits on CLFV μ and τ branching fractions [33] have been used to place indirect limits on CLFV J/ψ branching fractions [48][49][50]. In Ref.…”

“…As suggested by Zhang in Ref. [49], searching for the CLFV J/ψ decays with a huge sample at the BES remains a worthwhile experimental challenge. With a 58 M J/ψ event sample at BESII, the following upper limits have been established [51]: BR(J/ψ → τ ± e ∓ ) < 8.3 × 10 −6 ;…”

“…In particular, it may imply a nontrivial mechanism of self cancellation as discussed in Refs. [48][49][50], which are considered as unnatural.…”