Patent ID: 8143573

Claim:
A charged particle beam apparatus having a charged particle beam source producing a primary charged particle beam, a charged particle optical system including plural lenses and acting to focus the primary charged particle beam and to scan the beam over a specimen, detection means for detecting secondary charged particles produced from the specimen in response to the scanning of the primary charged particle beam and producing a detection signal indicating the secondary charged particles, and a control unit for controlling the lenses, the charged particle beam apparatus being adapted to acquire an image of the specimen using said detection signal from the detection means, wherein said control unit has: parallactic angle scanning control means for setting, via the charged particle optical system, a left tilt angle and a right tilt angle corresponding to a parallactic angle for the primary charged particle beam impinging on the specimen and controlling scanning of the primary charged particle beam such that the left tilt angle and the right tilt angle are given to the beam alternately for each one scanning line over the specimen; and parallax image formation means for acquiring left and right parallax images based on the detection signal produced from the detection means under the control of the scanning of the beam.