LCD device

A liquid crystal display device comprises an upper substrate, a liquid crystal layer, a lower substrate, an optics membrane and a light guiding plate which are in sandwich arrangement in turn. The invention further comprises a flexible circuit board and a light source, wherein, the flexible circuit board is arranged on the lower substrate; the light source is arranged at one side of the flexible circuit board adjacent to the light guiding plate; the light guiding plate comprises a top surface, the part of the top surface corresponding to the light source is defined as a light input zone, while the rest part of the top surface is defined as a light output zone. The light source of the liquid crystal display device is arranged on the flexible circuit board, and the part of the top surface corresponding to the light source is defined as the light input zone, thereby the area of the light input zone is enlarged, and consequently light usage factor of the liquid crystal display device is improved.