An electronic beam transmitting through a mask is detected by a detector in which a plurality of elements is aligned in a plurality of lines while an image signal is transferred by the detector synchronously with movement of the mask, and high resolution due to a short wavelength of the electronic beam can be effectively utilized as well as an image signal is transferred at right angles to a line of the detector synchronously with same time detection of pixels in a direction of the line, so that an inspection of a mask with high resolution at high speed would be achieved, and furthermore, it would be achieved to produce an image scanned in a straight line with the extremely high accuracy without zigzag scan when a stage with an easy structure is used.