Patent ID: 8740074

Claim:
An imaging apparatus for reading information, comprising: an image sensor obtaining an image of an object; a lens system including a single lens or a plurality of lenses, the lens system receiving light from an object and guiding the light to the image sensor while focusing; an iris limiting an incident range of light from each of points on the object; a transmissive spatial light modulator arranged at an opening of the iris provided in the iris and assigning a transmittance characteristic varying with a position to each of incident light whose incident range is limited by the iris; and a control unit controlling the transmittance characteristic of the transmissive spatial light modulator; wherein by adjusting a distance between the lens system and the image sensor so that a focus position of the lens system can be set in front of or behind a light-receptive surface of the image sensor, each of the incident light spreads within a predetermined range on the light-receptive surface, and by assigning the transmittance characteristic varying with a position to each of the incident light by the transmissive spatial light modulator, identical intensity distributions of each of the incident light overlap one another, and as a result a desirable low-pass filter is optically implemented on the image.