Thermal emissivity ∊ of cholesteric liquid crystal films is measured as a function of the film thickness d. ∊ increases from 0.2 to 0.4 in parallel with the increase of d from 13 µm to 33 µm and arrives at a constant value as high as 0.87 in the case of d ~ 1 mm. Reflectance at the air-to-liquid crystal interface and the absorption coefficient of the liquid crystal layer are found to be 0.130 and 7.24 × 10-3 µm-1, respectively. The dependency of ∊ on d is interpretable on the basis of McMahon’s theory of radiant characteristics of semitransparent radiators.
© 1978 Optical Society of America
Nobuya Tamura and Seiji Takata, "Thermal emissivity of semitransparent and opaque films of cholesteric liquid crystal," Appl. Opt. 17, 3051-3053 (1978)