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Abstract

A microcomputer software package was written to calculate the tranmission and reflection characteristics of multilayer thin films on a substrate. The program was written to be as "user-friendly", versatile and modular as possible. To test the program, a transparent oxide-type heat-mirror film capped with an antireflection coating was studied for greenhouse applications. Si0₂ and ZnO were considered as representative antireflection and heat-mirror materials respectively. The results of calculations of heat transfer coefficient and transmittance of the glazing construction polyethylene/air gap/Si0₂/ZnO/polyethylene are presented. The resulting structure is shown to give a visible light transmission spectrum which closely matches the plant sensitivity curve for plant growth and has higher thermal insulation compared to uncoated polyethylene.