<title>Laser-resisting holographic protective film</title>

Abstract

ABSTRACT In this paper, the structure design of laser-resisting holographic protective film is introduced; the effect of thethickness and coefficient of the holographic recording medium on diffraction efficiency, on protective bandwidth, and onprotective angle is analyzed: the testing results on the optical density, the protective angle, the effect of biologicalprotection for rabbits' eyes are presented. 1. BASIC PRINCIPLE Tactical laser weapons have become a threat to eyes and optoelectronic sensors. Laser resistance of holographicprotective film is achieved by the application of the principle of Bragg diffraction. This holographic film can effectivelyprotect against laser of specially designated wavelength, with little influence on the brightness of viewing field. It can bepasted on various optoelectronic devices, or used in making laser protective eye wears.The holographic protective film is obtained as a three-dimensional reflection phase grating with high transparentpolyester fiber as basic and dichromate gelatin as recording medium, in the method of laser hologram. When the entranceangle of laser satisfies the Bragg condition, powerful first order diffraction light can appear. According to requirement,by controlling the distance between neighboring interference fringes, the laser of specially designed wavelength can bereflected, but other light can pass this protective film with little attenuation.In the recording process of hologram, the Ar+ laser is used as recording optical source, the wavelength(. ) of therecording optical wave equals 0.5l4nm, and the angles of object light and reference light in medium are separately e,