Importance

Loading Importance Indicators...

Abstract

A bar code label is ready by automatically initiated scanning of the bar code symbol by a scanner on a stand. Light is reflected back to the scanner as from the bars of a code being scanned. Initially, the scanner is operated in a pulsed mode with low duty cycle (5%) pulses. These pulses are reflected from a reflective area unless an object is inserted and blocks the beam path. Then (because the beam is not scanning across the code) the reflected pulses (which are detected much like the bars and spaces of the code) are not detected. The ratio of the number of generated pulses to the reflected pulses is computed for a succession of pulses. If this ratio exceeds two (i.e., that the number of effective bars is less than the number of generated pulses during the succession), then the presence of the object is detected. The system, implemented in an application program in the microprocessor controller of the bar code scanner, initiates scanning of the bar code. Upon the detection of the code (a good read) or under conditions where the label is removed before a good read, or is not removed after a good read, the scanning mode is discontinued and the pulsing mode is again initiated. The pulsing mode is initiated continually to test for the presence of an object carrying a bar code label, when not scanning.

Loading the Abstract Image...

First Claim