Liquid crystal display device

A liquid crystal display device, comprising:

• a rectangular-shaped optical sheet that is arranged on a back face side of a liquid crystal panel, a light guide plate that is provided on a back face side of the optical sheet and emits light from a light source to the liquid crystal panel, and a back-face chassis that is provided on a back face side of the light guide plate, wherein
• a resin-made chassis that is inserted between a peripheral part of the optical sheet and a peripheral part of the light guide plate and forms an air layer between the optical sheet and the light guide plate is included,
• a plurality of ribs for engaging with a plurality of holes formed in the peripheral part of the optical sheet are formed in the resin-made chassis,
• the plurality of holes include a first hole that is formed in a center of one long side of the optical sheet, a second hole that is formed in a center of the other long side of the optical sheet and third holes that are formed along both short sides of the optical sheet,
• the first hole is restricted to be immovable in directions that are parallel and perpendicular to the long sides of the optical sheet when being engaged with the rib, the second hole is restricted to be immovable in the direction that is parallel to the long sides of the optical sheet when being engaged with the rib, and the third holes are movable in directions that are parallel and perpendicular to the short sides of the optical sheet when being engaged with the ribs.