There is provided a screen, which, with a simple configuration, is capable
of effectively utilizing light projected thereon and realizing an even luminance
distribution on the screen. This screen has a diffusion layer whose diffusion characteristic
expressed as a luminance distribution with respect to a scattering angle of incident
light incident at an angle of 0 is varied such that the peak position of
the luminance distribution is shifted towards a greater value of scattering angle
in the direction of the central portion of the screen the greater the distance
from the central portion of the screen is. The present invention also provides
an optical film suitable for use in such a screen, and a manufacturing method therefor.