Patent ID: 7880843

Claim:
A liquid crystal display device comprising a backlight, a liquid crystal display panel and a viewing angle control panel for switching a viewing angle of the liquid crystal display panel over between a first viewing angle and a second viewing angle which is within the first viewing angle and narrower than the first viewing angle, wherein: the viewing angle control panel comprises a first polarizing plate, a liquid crystal layer and a second polarizing plate stacked in this order, the viewing angle control panel comprises at least one phase difference plate at least one of between the first polarizing plate and the liquid crystal layer and between the second polarizing plate and the liquid crystal layer, when the viewing angle of the liquid crystal display panel is the first viewing angle, the liquid crystal display panel has a retardation value Re 1 of nλ/2−λ/4<Re 1 <nλ/2+λ/4 (n is an integer of 1 or more) at a white display portion, when the viewing angle of the liquid crystal display panel is the second viewing angle, the liquid crystal display panel has a retardation value Re 2 of nλ/2−λ/4<Re 2 <nλ/2+λ/4 (n is an integer of 1 or more) at a white display portion, and when the viewing angle of the liquid crystal display panel is the second viewing angle, the liquid crystal display panel has a retardation value Re 3 of nλ−λ/4<Re 3 <nλ+λ/4 (n is an integer of 1 or more) at a black display portion.