Patent ID: 6382509
Filing Date: 2002-05-07
Classification: G06K

Abstract:
A signal control method for a barcode scanner to accurately read a barcode on an object, comprising the steps of:a. using a laser element to generate light for detecting the object and indicating the correct address of the barcode, and not activating the scanner structure when the button key of the barcode scanner being pressed; b. applying a constant frequency oscillation wave on a laser diode which emits photo points at an oscillation fashion with same optical path of the barcode scanner, and receiving reflecting signal of a frequency same as the one applied on the photo points by a light detect sensor of the barcode scanner when the object entering in a readable range, and amplifying and processing the signal to obtain a correct reflection signal at an output pin, and confirming signal frequency being same as the emitting frequency from the laser diode to confirm the object having entered in the readable range; and c. converting the laser diode to constant current driving by the barcode scanner when the object has entered in the readable range and the laser photo points have projected on the scanning barcode for activating the scanner structure to change the laser photo points to a scanning line for reading the barcode.