IMAGE READER COMPRISING CMOS BASED IMAGE SENSOR ARRAY

摘要

The invention features an image reader and a corresponding method for capturing a sharp distortion free image of a target, such as a one or two-dimensional bar code. In one embodiment, the image reader comprises a two-dimensional CMOS based image sensor array, a timing module, an illumination module, and a control module. The time during which the target is illuminated is referred to as the illumination period. The capture of the image by the image sensor array is driven by the timing module that, in one embodiment, is able to simultaneously expose substantially all of the pixels in the array. The time during which the pixels are collectively activated to photo-convert incident light into charge defines the exposure period for the sensor array. In one embodiment, at least a portion of the exposure period occurs during the illumination period.

主权项

1. A an image reader for collecting image data from a target, the image reader comprising:
a CMOS based image sensor array, the CMOS based image sensor array comprising a plurality of rows of pixels, each of the pixels of the CMOS based image sensor array being an active pixel comprising a pixel amplifier, a photosensitive region and an opaque shielded data storage region; a housing encapsulating said image sensor array; wherein the image reader includes a first user selectable mode of operation and a second user selectable mode of operation; an illumination module configured to illuminate the target during an illumination period; wherein the image reader is operative so that with the second user selectable mode of operation active, exposure of pixels of a plurality of different rows of said CMOS based image sensor array is initiated sequentially responsively to an initiation of a decode attempt; wherein the image reader is operative so that with the second user selectable mode of operation active, exposure of pixels of a plurality of different rows of said CMOS based image sensor array is initiated simultaneously responsively to an initiation of a decode attempt.