Patent ID: 6950155

Claim:
A liquid-crystal display device comprising: a transmission type liquid-crystal display panel including a liquid-crystal cell, said liquid-crystal cell including a back-side substrate, a visual-side substrate, and a liquid crystal, said back-side substrate including a back-side transparent substrate, a low-refractive-index transparent layer which is lower in refractive index than the back-side transparent substrate, and a back-side transparent electrode, said visual-side substrate including a visual-side transparent substrate, and a visual-side transparent electrode, said liquid crystal being held between said back-side and visual-side substrates so that respective electrode sides of said back-side and visual-side substrates are disposed opposite to each other; at least one light source disposed on a side surface of said back-side transparent substrate; and an optical path control layer having a repetitive structure of optical path changing slopes disposed on a back side surface of said back-side substrate and being higher in refractive index than said low-refractive-index transparent layer, each of said optical path changing slopes being inclined at an inclination angle with respect to a reference plane of said back-side substrate, wherein said low-refractive-index transparent layer is disposed on a visual side of said back-side transparent substrate between said back-side transparent substrate and said back-side transparent electrode.