Patent ID: 6715685
Filing Date: 2004-04-06
Classification: G06K

Abstract:
In an electro-optical reader for directing a light beam to, and for detecting light reflected from, a bar code symbol to be read, a retro-reflective scan module, comprising:a) a generally planar, rectangular support; b) a light source supported by the support, for generating and directing the light beam along a first optical path; c) a selectively activatable first scan assembly including a generally planar, reciprocally oscillatable first scan mirror mounted in the first optical path for oscillating movement on the support to reflect the light beam from the light source along a second optical path, and a first drive for reciprocally oscillating the first scan mirror to sweep the light beam in a first direction across the symbol; d) an optical assembly mounted on the support, and including an optical element having a light-collection portion for collecting and re-directing the light reflected from the symbol, and a light-passage portion for allowing the light beam along the second optical path to pass through the light-collection portion; e) a second scan assembly including a generally planar, reciprocally oscillatable second scan mirror mounted in the second optical path for oscillating movement on the support to reflect the light beam received from the light-passage portion to be directed to the symbol, and also for simultaneously directly receiving the light reflected from the symbol and for directing the received reflected light to the light-collection portion, the second scan assembly including a second drive for reciprocally oscillating the second scan mirror to sweep the light beam in a second direction orthogonal to the first direction across the symbol; f) a controller operatively connected to the drives, for actuating both of the drives to oscillate both scan mirrors to sweep the symbol with a multiple line scan pattern, and for selectively deactuating one of the drives to sweep the symbol with a single line scan pattern; g) a sensor supported by the support, for detecting the collected reflected light re-directed by the light-collection portion and for generating an electrical signal corresponding to the symbol.