Design And Preparation Of Oil And Dust Proof Structures On The Surface Of Optical Instruments

Oil pollution and dust adhesion can be very harmful to optical instruments. Various kinds of oil pollution as well as dust adhere to the surface of optical systems, causing numerous troubles, such as vision unclear, material abrasion, mechanism blockage, results misreading, image contrast decreasing, luminous flux dropping, and so on. So much so that it is very necessary to protect the surface of optical instruments from oil pollution and dust.In this thesis, two different kinds of oil and dust prevention structures which could be used on optical instruments were prepared, one is SiO2-TiO2 double-layer nano-particle self-cleaning surface, and the other is electric curtain for removing dust on it. These two structures can effectively eliminate dust or oil adhering to the surface.For SiO2-TiO2 double-layer nano-particle self-cleaning surface, nano TiO2 and SiO2 particle layers were prepared by self-assembling method. First, the nano SiO2 particle layer was fabricated by spin-coating, with SiO2 nano-particles close-packed. Then the nano TiO2 particle layer was fabricated by dip-coating, with TiO2 nano-particles nonclose-packed. After that, we calculated the roughness of the as prepared nano SiO2 particle layer as well as that of nano SiO2-TiO2 particle layer. Also, the micro-structures of the as prepared self-cleaning structure were observed by SEM; In addition, the water contact angles of the as prepared self-cleaning array before and after UV light illuminating were determined by Drop Meter. Finally, the photo-induced catalytic ability was evaluated by taking use of methyl red and Spectrometer.For electric curtain, the parallel strip form electrodes were obtained by wet-etching, followed by a layer of insulation dielectric material prepared in the prevention of electrostatic breakdown. Then, the electrodes of the electric curtain were connected to an AC-voltage power supply, which provided power for the electric curtain to form standing wave on its surface. The performance of electric curtains was determined by comparing their performances when the gaps between electrodes, the amounts of dust covering on the curtain, and the voltages provided onto them were varied.