Patent ID: 6654110
Filing Date: 2003-11-25
Classification: G01N

Abstract:
An image pickup apparatus, comprising:a sample stage configured to move at a moving speed a sample whose image is to be taken in a first direction; a light source configured to emit a light beam; a diffraction grating configured to generate mÃ—n number of sub beams at predetermined intervals along a direction corresponding to the first direction and a second direction perpendicular to the first direction from said light beam, wherein said mÃ—n number of sub beams include a reflected light or a transmitted light configured to scan a surface of said sample; a beam deflection device configured to deflect said mÃ—n number of sub beams in the first direction; an image sensor configured to receive a transmitted light or a reflected light from said sample, having a plurality of light receiving elements arranged in a two-dimensional array along the first and second directions, to successively transfer at a charge transfer speed charges stored in a line of each of said plurality of light receiving elements arranged in the first direction, line by line, at a predetermined line transfer speed, and to successively output the charges stored in said plurality of light receiving elements; a spatial filter arranged between said sample stage and said image sensor, and having a plurality of slits formed at a predetermined pitch along the second direction and extending in the first direction, said reflected light and said transmitted light entering into said image sensor through each of said plurality of slits, and a first time interval being defined by the time necessary for said sample to move at said moving speed from a first position into which an i-th line of said mÃ—n number of sub beams enters, to a second position into which an i+1-th line of said mÃ—n number of sub beams adjacent to the second direction enters, and a second time interval is defined by the time necessary for said image sensor to transfer at said charge transfer speed the charge stored in the line of said plurality of light receiving elements into which a light having passed through an i-th slit of said plurality of slits of said spatial filter enters, to the line of said plurality of light receiving elements into which an illumination light having passed through an adjoining i+1th slit of said plurality of slits enters; and a drive control circuit configured to control a driving of said image sensor and said beam deflection device, said image sensor being controlled such that said first and second time intervals are equal, and said beam deflection device being controlled such that a movement of said mÃ—n number of sub beams forms irradiation areas that are continuous in the first direction.