Patent ID: RE41665

Claim:
An object observation apparatus comprising: a drivable stage on which a sample is placed; an irradiation optical system which is arranged to face the sample on said stage, and emits an electron beam as a primary beam; an electron detector which is arranged to face the sample, has a detection surface on which at least one of a secondary electron, a reflected electron, and a back-scattering electron generated by the sample upon irradiation of the electron beam is projected as a secondary beam, and generates image information of the sample; a stage driver which is adjacent to said stage to drive said stage; and a deflector arranged between the sample and said electron detector to deflect the secondary beam, said electron detector having: a converter arranged on the detection surface to convert the secondary beam into light; an array image sensor which is adjacent to said converter, has pixels of a plurality of lines each including a plurality of pixels, sequentially transfers charges of pixels of each line generated upon reception of light of an optical image obtained via said converter to corresponding pixels of an adjacent line at a predetermined timing, adds, every transfer, charges generated upon reception of light after the transfer at the pixels which received the charges, and sequentially outputs charges added up to a line corresponding to an end; and a controller connected to said array image sensor to output a transfer signal for sequentially transferring charges of pixels of each line to an adjacent line, and said controller having: a stage scanning mode in which said array image sensor is controlled in accordance with a variation in projection position of the secondary beam projected on said electron detector that is generated by movement of said stage device; and a deflector operation mode in which said array image sensor is controlled in accordance with a variation in projection position of the secondary beam projected on said detector that is generated by operation of said deflector.