Optoelectronic device and process for acquiring symbols, such as bar codes, using a two-dimensional sensor

A method of operating an optoelectronic device to acquire bichromatic machine-readable symbols, the optoelectronic device including a two-dimensional sensor having a plurality of pixels each capable of transmitting electrical signals representing a quantity of light incident on the respective pixel, the pixels arranged in a plurality of rows, the pixels in each of the rows extending in a scanning direction, and the plurality of rows arranged in a direction perpendicular to the scanning direction with respect to one another, the method comprising:

• receiving electrical signals from successive sets of the pixels along the rows in the scanning direction in at least a first pass along the rows, where the sets of the pixels extend across at least one row in the direction perpendicular to the scanning direction and each set of pixels has a first height in the direction perpendicular to the scanning direction during the first pass;
• and
• receiving electrical signals from successive sets of the pixels along the rows in the scanning direction in at least a second pass along the rows, the second pass successively following the first pass, where the sets of the pixels extend across at least one row in the direction perpendicular to the scanning direction and each set of pixels has a second height in the direction perpendicular to the scanning direction during the second pass, the second height different from the first height.

An optoelectronic device for acquiring bichromatic bar codes comprising:

• a reading window,
• sensor means with electronic scanning comprising a two-dimensional sensor comprising a plurality of individual detectors, known as pixels, transmitting electrical signals representing the quantity of light which they receive, the sensor means being adapted to carry out electronic scanning of at least a portion, known as scanned portion, of this two-dimensional sensor in a direction, known as scanning direction XX′, the pixels of the two-dimensional sensor being ordered in a plurality of h rows juxtaposed in a direction, known as direction YY′, perpendicular to the scanning direction XX′, the two-dimensional sensor extending in the direction YY′ over a height greater than a pixel, the scanned portion having a dimension in the direction YY′, known as height Hy, which is constant during each scanning operation, from one side to the other of the two-dimensional sensor in the scanning direction XX′, optical means adapted to form, at least on the scanned portion of the two-dimensional sensor, an image of a code to be acquired located opposite the reading window,
• wherein, in order to acquire a code placed opposite the reading window, the sensor means are adapted to carry out at least two scanning operations and to modify, between at least two successive scanning operations, the height Hy of the scanned portion of the two-dimensional sensor.

In an optoelectronic device for acquiring bichromatic bar codes comprising:

• a reading window,
• sensor means with electronic scanning in a global direction, known as scanning direction XX′ comprising a plurality of individual light detectors, known as pixels, transmitting electrical signals representing the quantity of light which they receive, these sensor means comprising a two-dimensional sensor of which the pixels are ordered in a plurality of h rows juxtaposed in a direction, known as direction YY′, perpendicular to the scanning direction XX′, this two-dimensional sensor extending perpendicularly to the scanning direction XX′ over a height greater than a pixel, the sensor means being adapted to carry out electronic scanning of at least a portion, known as scanned portion, of this two-dimensional sensor having a dimension in the direction YY′, known as height Hy, which is constant during each scanning operation, from one side to the other of the two-dimensional sensor in the scanning direction XX′,
• optical means adapted to form, on the sensor means, an image of a code to be acquired located opposite the reading window,
• a process for acquiring bichromatic bar codes, wherein, in order to acquire a code placed opposite the reading window, at least two scanning operations are carried out and, between at least two successive scanning operations, the height Hy of the scanned portion of the two-dimensional sensor is modified.