| Light reflection is a common phenomenon in everyday life. Disturbing reflection does not only impair the clearity of optical components, but also blemish image quality. In some cases, it can pose safety hazards. Therefore, antireflection coatings (AR) have been developed to eliminate or reduce such unwanted reflections. The AR structures play an important role in a variety of optical technology. Aample work, theoretical and experimental, has been done and a variety of methods have been developed. However, a method that is not only able to produce perfect and broadband antireflection coatings, but also simple, robust, low cost and suitable for massive production is still in search. With such idea in mind, we are, in this work, pursuing the methods suitable for preparing high performance and large area AR coatings.A novel double-layered (DB) AR coating composed of inorganic inner layer and polymeric outer layer was prepared by draining the coating solution while holding the glass slide still in solution tank. The reflective index (nD) of SiO2/TiO2 hybrid sol-gel and the copolymers were studied. nd of the inner and outer layers were adjustable in the range of 1.45～2.0 and 1.49～1.60, respectively. Photo treating of the inorganic layer with UV light decreased the thickness and increased nD. Transmittance of the coated slides in 420～600 nm were greatly increased to the maximum value of 99.5%. The wavelength of highest transmittance was adjustable by controlling the thickness of films.In another way, antireflective structures were prepared by controlled assembling of nanoparticles to form a nanoporous monolayer. The antireflective coatings on glass slides were prepared at first time by spin casting polymer latex. Optical transmittances, at 550nm, of 95.7% for single sided and 99.5% for double sided coating were achieved. Structure investigations with AFM, SEM, revealed that the antireflective coatings were highly porous and affected by spin speed, the concentration and particle size of PMMA latex. Small amount of additives such as PEG, PVA were used to improve the adhesion of nanocoating. When SiO2 sol was used as additive, the composite nanocoating was calcined to remove organic particles, and the resultant SiO2 coating possessed both high transmission (95.7% for single side coating) and good adhension to the glass substrate. AR properties of dip coated particle films were also studied. Comparing to spin method, transmission of dip coated film was suboptimal due to the close packing of nano particles. The spin coating may be a better method for mass production, due to its conveniences, low cost and good reproducibility.
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