LIQUID CRYSTAL DISPLAY DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a liquid crystal display device which is improved in the luminance of a display screen of a liquid crystal display panel than heretofore. SOLUTION: The liquid crystal display device is furnished with the liquid crystal display panel having liquid crystals held between a pair of substrates and a back light arranged on the side opposite to the display surface of the liquid crystal display panel, in which the back light has a light source for irradiating irradiation light to the liquid crystal display panel and first and second optical elements for condensing the irradiation light from the light source. The first optical element has a multiplicity of first prism elements formed at specified intervals on a first main surface and the second optical element has a plurality of second prism elements which are formed at random intervals on the first main surface and intersect with the ridge line direction of the first prism elements. The second prism elements have the zigzag ridge lines and are so arranged that the ridge line direction parallels to the extension direction of the light source.