Patent ID: 7796215

Claim:
A liquid crystal display device, comprising: a first liquid crystal display panel and a second liquid crystal display panel located back to back, wherein: the first liquid crystal display panel includes a first substrate, a second substrate located opposite from the second liquid crystal display panel with respect to the first substrate, a first liquid crystal layer provided between the first substrate and the second substrate, and a first polarizing element located opposite from the first substrate with respect to the first liquid crystal layer; and the second liquid crystal display panel includes a third substrate, a fourth substrate located opposite from the first liquid crystal display panel with respect to the third substrate, a second liquid crystal layer provided between the third substrate and the fourth substrate, and a second polarizing element located opposite from the third substrate with respect to the second liquid crystal layer; the liquid crystal display device further comprising: a first light source, provided to a side of the first substrate of the first liquid crystal display panel, and arranged to emit light toward a side surface of the first substrate; a second light source, provided to a side of the third substrate of the second liquid crystal display panel, and arranged to emit light toward a side surface of the third substrate; and a third polarizing element provided between the first liquid crystal display panel and the second liquid crystal display panel; wherein the first substrate includes a first light guide layer arranged to direct light, which is incident on the first substrate from the first light source and propagating inside the first substrate, toward the second liquid crystal display panel; and the third substrate includes a second light guide layer arranged to direct light, which is incident on the third substrate from the second light source and propagating inside the third substrate, toward the first liquid crystal display panel.