An image analysis device 1 is equipped with the photoreceptive means 11
that optically acquires diffraction pattern A that appears on the
fluorescent screen 24 in order to obtain the diffraction pattern resulting
from reflection high-energy electron diffraction, and the
halation-prevention filter 12 provided so as to transmit the visible light
emitted from the diffraction pattern A of the fluorescent screen 24, along
the light path connecting the photoreceptive means 11 and the fluorescent
screen 24. Also, the filter 12 is varied so that the transmittance of the
visible light transmitted through the filter 12 is minimum at the filter
center and increases with the distance from the center.
