PURPOSE: To make a scanning image during observation so as not to come out of sight, by storing a state of things on an X-Y transfer mechanism and a turning mechanism just before sample turning operation in memory as an initial signal in advance, while driving these mechanisms in the reverse direction to a transition signal indicating variations.

CONSTITUTION: Driving control for each of motors 15 and 16 for X-Y direction transferring is performed by operations of an X transfer knob 20, a Y transfer knob 21, a tilt knob 22 and a turning knob 23 all connected to a central control circuit 19. As for the turning knob 23, there is provided with a select circuit 24 between this knob and the central control unit 19, while this select circuit 24 is so constituted as to cause a turning signal on the sight turning control given by the turning knob 23 to be impressed on a luminescent line display circuit 25 or the central control circuit 19 according to an input signal out of a set circuit 26. The central control circuit 19 controls so as to perform a sight shift in the reverse direction to the sample movement based on sample rotation whereby a sight slippage in a cathode-ray tube picture screen is prevented from occurring.