Influence of Light Source and Cathodoluminescence on the Color Parameters of Ruby Red

Abstract:

According to different light sources and cathodoluminescence (CL) intensity, the performance of color parameters (lightness L^*, chromaticity a^* and b^*, chroma C^*, hue angle h_o) and chromophore contents (Cr³⁺, åFe) are studied to analyze the impact of all these elements on ruby red color. Ruby red under the standard light source D65 (a^*=5.65 ~ 26.97, b^*= -5.43~3.98) is similar with the color under natural sun-light. Purplish red h_o Î (354.14°, 0.7°) with medium-low lightness (L^* = 32 ~ 40) under D65 displays the best visual appearance, showing a relatively high value. Comparing with D65, standard light source A reveals ruby a deep red hue (a^* = 10.61 ~ 37.39, b^* = -6.59 ~ 7.50). Because of the strongest spectrum power distribution in the orange range and fluorescence of light source U30, the hue of orangish tone is mixed in ruby red (a^* = 6.92 ~ 31.23, b^* = 0.31 ~ 9.34). It is illustrated that åFe can inhibit the intensity of CL which is compared in different voltages. Low lightness purplish red is easy to be influenced by CL and always shows strong luminescence correspondingly. It is concluded that ruby purplish red has strong luminescence of CL which is usually supported by a few of åFe and medium-low lightness under D65, which has an excellent visual perception.

• Periodical: Key Engineering Materials (Volume 492)
• Pages: 379-383
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.492.379
• Online since: September 2011
• Authors: Xiang Li, Ying Guo
• Keywords: Cathodoluminescence, Light Source, Ruby Red

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