Study on Antireflection Film Based on Nano Pore

Abstract

Optical anti-reflection film is an important branch of thin film optics, and its application spreads throughout all fields of optics. Generally, the materials for preparing optical anti-reflection films are magnesium fluoride, calcium fluoride and some fluorinated polymer polymers with good thermal stability so that the equivalent refractive index of the substrate and the film is reduced, and then the substrate refractive index matches the air refractive index to achieve the purpose of increasing anti-reflection. The characteristics of these materials are that they all have a relatively low refractive index. Among these materials, its application is most common due to the low refractive index of magnesium fluoride (MgF2, refractive index 1.38). However, if a magnesium fluoride film is coated with glass as a substrate, it still has a reflection loss of about 1.5%. Polymer nanoporous films can achieve a relatively low refractive index, thereby achieving the refractive index requirements of high transmittance anti-reflection films on the refractive index of materials; The spin coating film preparation process adopted is simple and the preparation cost is low; In terms of optical properties, the anti-reflection effect of polymer nanoporous films is also far superior to that of traditional anti-reflection films. In addition, its most prominent advantage is that the refractive index specified nanoporous polymer film can be obtained through the control of porosity, which will make the nanoporous polymer film widely used in optical films and optoelectronic devices and other fields. In this paper, a low refractive index thin film material with adjustable refractive index is prepared by using nanophase separation technology of polymer materials to meet the needs of various substrate pairs of anti-reflection films. This paper introduces the principle of increasing anti-reflection, the preparation of thin films and their optical performance tests.