| 摘要 |
[OBJECTIVE] The objective of the present invention is to provide a light guide film for an ultra-thin liquid crystal backlight which can be made thin and can prevent the deterioration of luminance and uniformity. Also, the objective of the present invention is to provide an ultra-thin liquid crystal backlight unit and a portable computer. The ultra-thin liquid crystal backlight unit prevents the luminance variations by preventing the deterioration of luminance and uniformity of a beam emitted from a light guide film, and also is made thin. [SOLUTION] A light guide film according to the present invention is a light guide film for an ultra-thin liquid crystal backlight unit with an average thickness of 600 μm or less. The retardation value (Re) is 50 nm or less. An average residual stress is 8 × 10^5 Pa. |
