Abstract: A one-dimensional scanner system for two-dimensional image acquisition includes a flying spot scanner for scanning in a line at a first velocity in a first direction across an object which is moving at a second velocity in a second direction transverse to the first direction; the first and second velocities establish a first sample rate in the second direction for defining a pixel size in the second direction; a timing device for detecting the velocity of the object in the second direction and generating a sample rate in the first direction and a frame accumulator for reading and storing each line scanned, assembling a two-dimensional image of the object and reading out that image; the frame accumulator including a compensation device responsive to the second sample rate for normalizing the second sample rate with the first sample rate to eliminate distortions in the pixel size and two-dimensional image in the first direction.

Abstract: An intensity compensated scanning system includes laser means for providing a laser beam; scanner means for sweeping the laser beam in an arcuate path across a surface to be scanned; means for sensing the return laser beam reflected from the surface to be scanned; means for quantifying the decrease in the intensity of the return laser beam at the scan extremity portion relative to the intermediate scan portion; and means responsive to the means for quantifying for varying the power to the laser means at the scan extremity portion relative to that at the intermediate scan portion for balancing the intensity of the return laser beam reflected from the surface to the means for sensing.

Abstract: A bar code reader system for reading bar code labels with highly specular spaces and bars with low contrast. The bar code label is illuminated with radiation polarized in a first direction. The radiation polarized in a first direction reflected from the bar code label is received and blocked by means of cross polarization. This blocked radiation is representative of the spaces and other radiation passing through unblocked is representative of the bars. The resulting radiation pattern representative of the bars and spaces is consequently inverted from its initial state into a secondary state. The radiation image passed by the block is detected in order to generate a signal representative of the bars and spaces. The strength of the signal representing the spaces is substantially diminished in intensity. The widths of the areas representing the bars and spaces is determined, and the widths representing the bars and spaces are interpreted to obtain the information of the bar code.

Abstract: An improved bar code reading system for reading bar codes having a wide range of intensity of reflected radiation includes repeatedly scanning a beam of radiation across a bar code containing bar and space code elements; monitoring the number of scans of the beam across the bar code; sensing the radiation reflected from the bar code and providing a bar code signal representative thereof; the bar code signals are amplified at one of a number of different gains, and a different gain is selected for each scan. Also disclosed is an improved bar code reader system for reading bar codes of diffuse bar elements and specular spaced elements.