Diffraction properties studies of windshield-laminated photopolymer holograms

摘要

A windshield laminated hologram is an important application in automotive head-up displays. Properties of these holograms generally produce changes during processing. To predict changes accurately, the diffraction efficiency measurement etc. were apparently used to characterize their diffraction properties. This paper considers the actual structure of a windscreen which is composed of photopolymer hologram within the laminate. The photopolymer hologram, which was sandwiched between a polyvinylbutyral layer and glass ply, was treated at high temperature up to 140$DGR@C and about 12.5 kg/cm$+2$/ pressure; as used in a standard windscreen production process. The fringe planes of laminated hologram are generally sensitive to external parameters during process, such as pressure effects. In this paper, the pressure effect on diffraction properties is investigated to characterize windshield laminated photopolymer holograms. A theoretical model was proposed to approach the pressure effect in fringe plane of laminated hologram. A comparison of nonslanted and slanted holograms are analyzed with experimental data.