The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 01, 2012
Filed:
Jun. 23, 2010
Mark Weitzner, Plainview, NY (US);
James Giebel, Centerport, NY (US);
Mark Weitzner, Plainview, NY (US);
James Giebel, Centerport, NY (US);
Symbol Technologies, Inc., Holtsville, NY (US);
Abstract
In an electro-optical reader, an aiming or a scanning laser has an internal laser chip and a monitor photodiode. A controller deenergizes the chip in a deenergized state, and energizes the chip to emit a laser beam with an output power in an energized state. A positive voltage power supply forward biases and maintains the photodiode at a substantially constant positive voltage below a threshold voltage, to support a substantially constant photodiode leakage current in both states. A signal processor supports a total current comprised of a main photodiode current indicative of the output power of the laser beam in the energized state and of the leakage current which flows opposite to the main current, and removes the leakage current from the total current to output only the main current in the energized state.