Thin-film multilayer systems for use in a head-up display

#1. Field of the Invention

#The present invention relates to high color fidelity thin-film multilayer systems for use in head-up displays, and more particularly to a combiner of head-up displays, wherein the reflectance is independent of variance in wavelength throughout the visible light range.

#2. Description of Prior Art

#The following detailed description, given by way of example and not intended to limit the invention solely to the embodiments described herein, will best be understood in conjunction with the accompanying drawings in which:

#FIG. 1 is a diagram illustrating the structure of thin-film multilayer systems for use in head-up displays according to the present invention;

#FIG. 2 illustrates the relationship between the incident light wavelength and the s-polarized light reflectance with different incident angles in the first embodiment of this invention;

#Referring to FIG. 1, a thin-film system for use in ahead-up display according to the present invention comprises: A substrate 10 such as glass or plastic; a plurality of dielectric layers 20 having a high refractive index, such as TiO.sub.2, which has a refractive index of around 2.25, sequentially formed on the substrate 10; and a plurality of dielectric layers 30 having relatively a low refractive index, such as SiO.sub.2, which has a refractive index of around 1.45, alternately formed with the plurality of dielectric layers having a high refractive index 20.

#The first embodiment is a thin-film multilayer system for use in a head-up display with an anti-glare function. Table 1 lists the thickness and the material of each layer of the thin-film multilayer system, which is designed according to the interference theory for all-dielectric thin-film multilayers.

#TABLE 1 ______________________________________ Layer Material Thickness (nm) ______________________________________ Substrate Glass 1 TiO.sub.2 10.00 2 SiO.sub.2 41.12 3 TiO.sub.2 10.00 4 SiO.sub.2 28.32 5 TiO.sub.2 27.55 6 SiO.sub.2 42.64 7 TiO.sub.2 33.82 8 SiO.sub.2 64.53 9 TiO.sub.2 20.98 10 SiO.sub.2 76.61 11 TiO.sub.2 79.01 External Medium Air ______________________________________