Armaly B F, Look D C
Appl Opt. 1973 Aug 1;12(8):1904-8. doi: 10.1364/AO.12.001904.
An expression for the directional transmittance of an absorbing thin film on anabsorbing substrate was developed by using the classical electromagnetic theory. This expression when combined with the wellstudied reflectance can yield absorptance values that are of utmost interest in heat transfer studies. The behavior of the normal and hemispherical reflectance, absorptance, and transmittance is exhibited for some selected values of film and substrate optical constants and is presented graphically as a function of film optical thickness. The results indicate that the imaginary part of the complex index of refraction for both film and substrate should be accounted for when calculating radiative transfer and properties of such films.
利用经典电磁理论推导了吸收性基底上吸收薄膜的定向透射率表达式。该表达式与已充分研究的反射率相结合，可得出在传热研究中极具意义的吸收率值。针对薄膜和基底光学常数的一些选定值，展示了法向和半球反射率、吸收率及透射率的特性，并以薄膜光学厚度的函数形式绘制成图。结果表明，在计算此类薄膜的辐射传递和特性时，应考虑薄膜和基底复折射率的虚部。
