PURPOSE: To regulate the spatial effect by composing a pair of reflection electron detecting elements to regulate the position as desired at the position on the same plane almost vertical to a charged particle beam.

CONSTITUTION: When an electron beam 1 is radiated on a sample 4 on a sample stage 3, signals of the secondary electrons, the reflecting electrons, and the like are generated from the surface of the sample 4. Of these signals, the reflecting electrons 5a and 5b are in the same directions separated from the scanning area of the incident electron beam 1, and they can be detected by a pair of semiconductor reflection electron detecting elements 6a and 6b which are provided on the same plane almost vertical to the incident electron beam 1. The detected signals include the composition signal and the unevenness signal of the sample 4 surface respectively at the same time, and since the detecting elements 6a and 6b are provided in the same direction to the incident electron beam 1, a stereoscopic picture image including the composition signal and the unevenness signal can be formed by adding and processing the signals detected by the detecting elements 6a and 6b.