A displacement sensor comprising an imaging unit and an
image processing unit. The imaging unit comprises a
two dimensional imaging device and a drive
control unit. The
two dimensional imaging device includes a group of light receiving pixels arranged in a matrix so as to correspond to a
field of view of a standard imaging unit, a plurality of
vertical shift registers corresponding to different columns of the pixels, and a horizontal register for receiving the outputs of the
vertical shift registers from top stages thereof, a photosensitive pixel region being defined in a prescribed horizontal band having a sufficiently narrower width than that would be provided by the total number of horizontal lines and interposed between a front optically black pixel region and a back optically black pixel region. The drive
control unit controls, according to a commanded
electric charge transfer protocol, a feeding of
signal electric charges from each light receiving pixel to the
vertical shift register of a corresponding column, a
vertical transfer of
signal electric charges in the vertical
shift register of each column, and a horizontal transfer of
signal electric charges in the horizontal
shift register. The
image processing unit comprises
electric charge transfer protocol command means for giving an
electric charge transfer protocol to the drive
control unit of the imaging unit in dependence of a content of the image process.