Light diffusing sheet and backlight using same

A light diffusing sheet comprising a diffusion layer, wherein the diffusion layer has a surface profile that satisfies the following conditions 1 and 2 and/or the following condition 3:

• Condition 1:
• a condition under which when the kurtosis (JIS B0601, 2001) of a roughness curve as determined by two-dimensional surface profile measurement is represented by Rku, Rku is not less than 3.0,
• Condition 2:
• a condition under which when the arithmetic mean roughness (JIS B0601, 2001) as determined by two-dimensional surface profile measurement is represented by Ra, Ra is not more than 1.5 μm, and
• Condition 3:
• a condition under which when the mean height (JIS B0601, 2001) of roughness curve elements as determined by two-dimensional surface profile measurement is represented by Rc and the mean length (JIS B0601, 2001) of roughness curve elements as determined by two-dimensional surface profile measurement is represented by RSm, the ratio of RSm to Rc (RSm/Rc) is not less than 7.0.