LIQUID CRYSTAL DISPLAY DEVICE AND BACK-LIGHT DEVICE

摘要

In a backlight unit provided with a plurality of optical sheets, a first optical sheet is characterized b y having different coefficients of linear expansion in two different directions (a first direction and a second direction) with the coefficient of linear expansion in the first direction larger than that in the second direction. A second optical sheet is arranged adjacently to the first optical sheet. The coefficient of linear expansion of the second optical sheet in approximately the same direction as the first direction of the first optical sheet is approximated to the coefficient of linear expansion of the first optical sheet in the first direction.