摘要:
A laser scanning bar code symbol reading system for scanning and reading poor quality or damaged bar code symbols. The system includes a housing having a light transmission window; an extremely-elongated laser beam production module for producing an extremely-elongated laser beam having (i) a direction of propagation extending along a z reference direction, (ii) a height dimension being indicated by the y reference direction, and (iii) a width dimension being indicated by the x reference direction, where x, y and z directions are orthogonal to each other. Each extremely-elongated laser beam is characterized by an elongation ratio (ER) that is defined as Y/X>4.5 for any point within the working range of the laser scanning bar code symbol reading system, extending along the z direction; where (i) Y indicates the beam height of the extremely-elongated laser beam measured in the Y reference direction, and X indicates the beam width of the extremely-elongated laser beam measured in the X reference direction, and (iii) the beam height (Y) and the laser beam width (X) are measured at 1/e2 intensity clip level. A laser scanning mechanism is provided for scanning the extremely-elongated laser beam out the light transmission window and across a scanning field defined external to the housing, in which a bar code symbol is present for scanning by the extremely-elongated laser scanning beam.
摘要:
The system includes a housing having a light transmission window and produces an extremely-elongated laser beam having an elongation ratio (ER) that is defined as greater than 4.5 for any point within the working range of the laser scanning bar code symbol reading system. A laser scanning mechanism is provided for scanning the extremely-elongated laser beam out the light transmission window and across a scanning field defined external to the housing, in which a bar code symbol is present for scanning by the extremely-elongated laser scanning beam.
摘要:
A method of selectively generating one or more scan lines from a multi-scan line scanner involves measuring the pulse widths of the pulses in a signal output of a motor driving the polygon mirror of the scanner wherein the signal relates to the position of the polygon's mirror facets. By measuring and distinguishing each of the pulses in the signal, the illumination of the scan beam can be synchronized with the rotation of the polygon mirror to only generate a desired number of scan line patterns that is less than the full complement of the scan line patterns capable of being generated by the multi-scan line scanner.
摘要:
A method of selectively generating one or more scan lines from a multi-scan line scanner involves measuring the pulse widths of the pulses in a signal output of a motor driving the polygon mirror of the scanner wherein the signal relates to the position of the polygon's mirror facets. By measuring and distinguishing each of the pulses in the signal, the illumination of the scan beam can be synchronized with the rotation of the polygon mirror to only generate a desired number of scan line patterns that is less than the full complement of the scan line patterns capable of being generated by the multi-scan line scanner.