PURPOSE: To obtain the liquid crystal display device which has no interference fringe and is bright and high in display quality by combining a light diffusion sheet laminated on plural lens plates which are laminated on a light-transmissive flat plate and arranged so that lens ridge lines cross one another.

CONSTITUTION: The light-transmissive flat plate 21, the lens plates 22 which are laminated on the flat plate 21 and arranged so that the lens ridge lines cross one another, and the light diffusion plate 23 laminated on the lens plates 22 are used as a light guide diffusing means 2 which is arranged on the back of a liquid crystal panel 1. The light guide diffusing means 2 for the liquid crystal panel 1 which has plural electrodes arranged in parallel is constituted by forming striped lenses so that the pitch of the lens ridge lines of the lens plates 22 is narrower than the pitch of the electrodes of the liquid crystal panel 1 and laminating the light diffusion sheet 23 on the lens plates 22. Consequently, even when the flat plate 21 is made thin, light is spread almost equally and made uniform in luminance by the diffusion sheet 23 before it reaches the liquid crystal panel 1, so neither interference nor a large decrease in luminance is caused.