| 摘要 |
PROBLEM TO BE SOLVED: To prevent the position of a restriction hole of a diaphragm plate from being displaced from the center line of an electron beam by the thermal expansion of a diaphragm plate holder. SOLUTION: This holder supporting device is provided with a holder support member 26 passing through a lens-barrel 2 and supported movably in an axial direction and turnably within an X-Y plane; a holder 28 connected to the inner end of the holder support member 26 through a piezoelectric material 27 expansible in a Y-axis direction; the diaphragm plate 29 provided at the inner end part of the holder 28 and having a charged particle beam irradiation part (the restriction hole) arranged in the passing position of charged particle beams; a Y-axis direction coarse adjusting mechanism U1 capable of coarsely adjusting the Y-axis direction position of the holder support member 26 and a Y-axis direction fine adjusting mechanism U2 capable of making fine adjustment; and a thermal expansion displacement preventing device for adjusting the Y-axis direction position of the diaphragm plate 29 by driving the piezoelectric material 27 according to the detected temperature of a temperature sensor 31 so as to cancel the Y-axis direction position change of the charged particle beam irradiation part caused by the thermal expansion of the holder 28.
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