SCANNING MICROSCOPE

摘要

PROBLEM TO BE SOLVED: To correct the orthogonality, distortion and aspect ratio of an image precisely and easily in response to a plurality of accelerating voltages and WD by inputting calculation results on rotation angle setting correction and other corrections into a plurality of four-quadrant multiplication DACs, and making these corrections with the multiplication DACs. SOLUTION: Sweep signals Xo(t), Yo(t) generated from a scanning signal generating circuit are inputted to multiplication DACs: DX, DY, and magnifying power, accelerating voltage interlock, and distance (WD) interlock between an objective lens top face and a sample are set, then part of them is inputted to four-quadrant multiplication DACs: DX-1X, DY-1X, DX-1Y, DY-1Y controlling upper scanning coils 1X, 1Y, and the other part is inputted to four-quadrant multiplication DACs: DX-2X, DY-2X, DX-2Y, DY-2Y controlling lower scanning coils 2X, 2Y. Rotation angle setting, orthogonality correction and aspect ratio correction are made, then desired scanning currents are fed to scanning coils.