Abstract: A liquid crystal display device includes a liquid crystal panel and an illumination device. The illumination device has a light guide plate and at least one spot light source on at least one side surface of the light guide plate. The light guide plate includes a large number of upper-surface arcuate cross-sectional grooves in a direction orthogonal to the one side surface on a surface thereof which faces the liquid crystal panel, and a large number of light-incident-surface arcuate cross-sectional grooves are formed in a thickness direction of the light guide plate on at least a portion of the one side surface which faces a position at which the spot light source is arranged. A relationship is provided between a contact angle Oa of the upper-surface arcuate cross-sectional grooves and a contact angle Ea of the light-incident-surface arcuate cross-sectional grooves.

Abstract: A liquid crystal display device formed as a both-side liquid crystal display device can suppress the generation of brightness irregularities generated on a main liquid crystal display panel thereof and can display an image with a uniform brightness over the whole screen to an extent that a uniform brightness is obtained in practical use. On a bottom surface of a first recessed portion formed in a casing, an optical sheet is arranged such that the optical sheet bridges over an opening, and a proper amount of color pigment is added to the casing on which the optical sheet is arranged in a contact state, thus making the reflectance wavelength characteristic of the surface substantially equal to the reflectance wavelength characteristic of a portion of the sub liquid crystal display panel.

Abstract: A liquid crystal display device includes a liquid crystal panel and an illumination device. The illumination device has a light guide plate and at least one spot light source on at least one side surface of the light guide plate. The light guide plate includes a large number of upper-surface arcuate cross-sectional grooves in a direction orthogonal to the one side surface on a surface thereof which faces the liquid crystal panel, and a large number of light-incident-surface arcuate cross-sectional grooves are formed in a thickness direction of the light guide plate on at least a portion of the one side surface which faces a position at which the spot light source is arranged. A relationship is provided between a contact angle Oa of the upper-surface arcuate cross-sectional grooves and a contact angle Ea of the light-incident-surface arcuate cross-sectional grooves.

Abstract: A liquid crystal display device formed as a both-side liquid crystal display device can suppress the generation of brightness irregularities generated on a main liquid crystal display panel thereof and can display an image with a uniform brightness over the whole screen to an extent that a uniform brightness is obtained in practical use. On a bottom surface of a first recessed portion formed in a casing, an optical sheet is arranged such that the optical sheet bridges over an opening, and a proper amount of color pigment is added to the casing on which the optical sheet is arranged in a contact state, thus making the reflectance wavelength characteristic of the surface substantially equal to the reflectance wavelength characteristic of a portion of the sub liquid crystal display panel.