US Patent 7932971 Liquid-crystal display

In a liquid-crystal display, unpolarized light from a light source passes through a linear polarization separation layer and strikes a liquid-crystal cell. The liquid-crystal cell, in response to an applied electrical field, changes the direction of a director, so as to change the direction of the electrical field oscillation vector of the incident linearly polarized light by substantially 0 to 90°, this light then striking a dichroic linear polarization layer on the surface, whereby only a component coincident with the polarization transmission axis thereof is allowed to exit to the outside. The dichroic linear polarization layer transmits 50% of this incident light, and absorbs the remaining 50%.