The fading rates of plastic plates dyed with a quinoline derivative (quinophthalone) have been measured under exposure to light of 366-, 404.7-, and 435.8-nm wavelengths and to a high pressure Xe arc. The initial quantum yield of fading is 2 × 10-5 and is independent of incident wavelengths. The correlation between the fading by lamp exposure and that by solar exposure is obtained using a filtered 1000-W Xe arc, a simulated solar radiation source. The fading plates provide simple and inexpensive means to measure the integrated lamp output and solar energy.
Hideo Okabe, "Fading of quinoline dye by light: application to the measurement of the integrated lamp output and solar energy," Appl. Opt. 20, 4054-4058 (1981)