Patent ID: 8345149

Claim:
An imaging apparatus for reading information, comprising: an iris for limiting the light-receptive range of the light from an object to be shot; a density filter arranged at an aperture of the iris or near the aperture and having the varying transmittance with the position; a lens; and an image sensor, wherein a distance between the lens and the image sensor is adjusted so that an image forming position of the lens can be set in front of or backward a light-receptive surface of the image sensor, thereby causing light from one point of the object to be shot to enter a plurality of pixels adjacent to a corresponding pixel of the image sensor with a light power distribution depending on a transmittance characteristic of the filter and causing light entering and centering on the plurality of pixels to partly enter the corresponding pixel of the image sensor spreading; wherein the distance between the lens and the image sensor is adjusted so that spread of an image on the light-receptive surface of the image sensor can be a length of three pixels or more in diameter when the image forming position is set in front or backward the light-receptive surface of the image sensor.