US 6,981,642 B2
Non-parallax optical auto-focusing system and method
Mark Krichever, Hauppauge, N.Y. (US)
Assigned to Symbol Technologies, Inc., Holtsville, N.Y. (US)
Filed on Jul. 17, 2003, as Appl. No. 10/621,283.
Prior Publication US 2005/0011952 A1, Jan. 20, 2005
Int. Cl. G06K 7/10 (2006.01)
U.S. Cl. 235—454 22 Claims
OG exemplary drawing
 
1. A non-parallax optical auto-focusing system comprising:
a moveable lens;
an actuator coupled to the lens for moving the moveable lens along an optical axis;
a first beam splitter positioned in the optical axis on a first side of the moveable lens for directing at least a portion of an aiming beam along the optical axis and toward an externally located optical target for generating a reflected aiming beam;
a second beam splitter positioned in the optical axis on a second side of the moveable lens for redirecting at least a portion of the reflected aiming beam at an angle perpendicular to the optical axis, wherein the first and second sides in the optical axis are substantially opposite with respect to each other;
a sensor assembly having a photodetector adapted to receive the redirected reflected aiming beam, and determine a parameter of the redirected reflected aiming beam, and having means for generating an output signal based on the determined parameter; and
an image sensor wherein said output signal is used for focusing an image of the optical target onto the image sensor.