Electro-optical scanner having stationary, multi-surface mirror having surfaces with aplanar profiles

Abstract

An optical scanner for reading indicia having areas of different light reflectivity, such as bar code symbols includes a stationary, multi-surface, fold mirror having a first surface of a first aplanar profile and a second surface of a second, different aplanar profile.

1. An optical scanner for scanning indicia having areas of different light reflectivity, comprising:
 a light source for producing a light beam; and  
 a scanning optical element for receiving the light beam and producing a scanning light beam therefrom, and a stationary, beam-shaping fold mirror comprising a cylindrical mirror for shaping the light beam.  
 
     
     
       2. An optical scanner for scanning indicia, the scanner comprising:
 a light source producing a light beam that converges in both x and y directions so that the light beam has a waist in both the x and y directions, where x and y are orthogonal directions; and  
 a scanning element positioned to receive the light beam and reflect the light beam in a scanning motion along the x direction across the indicia, and a stationary fold mirror including a convex beam-shaping surface shaped to diverge light in the y direction to at least reduce convergence of the light beam in the y direction.  
 
     
     
       3. The optical scanner of  claim 2 , wherein the convex surface is substantially cylindrical about an axis extending in the x direction so as to produce divergence of light in the y direction. 
     
     
       4. In an optical scanner for reading indicia having parts of different light reflectivity, the scanner having a laser light source, a reciprocally oscillatable scanning mirror for reflecting light from the light source to the indicia in a scan across the indicia thereby reflecting light of variable light intensity off the indicia, and a light sensor for detecting at least a portion of the light reflected off the indicia and generating an electrical signal indicative of the detected light intensity, an optical component comprising:
 a stationary mirror having a generally concave first surface portion for collecting at least a portion of the light reflected off the indicia, and for directing the collected portion of light to the light sensor, and a generally aplanar second surface portion for directing the light from the light source to the scanning mirror.  
 
     
     
       5. An optical scanner for scanning indicia such as bar code symbols, comprising:
 a laser source comprising a laser diode for producing a light beam along a path, the light beam having a profile that converges in both x and y directions so that the beam has a waist in each of the respective x and y directions, where x and y are orthogonal directions in a plane substantially orthogonal to the path of the light beam;  
 a convex mirror disposed in the path of the light beam from the laser source and shaped to diverge light in the y direction; and  
 a scanning element positioned to receive the light beam and functioning to move the light beam in a scanning motion along the x direction across the indicia.  
 
     
     
       6. In an optical scanner for scanning indicia, the scanner including a photodetector for detecting light of variable intensity reflected from the indicia and for generating an electrical signal indicative of the detected light intensity, an arrangement comprising:
 a light source for emitting a laser beam;  
 a scanning element disposed in a path of the emitted laser beam and operative to reflect the laser beam in a scanning path for scanning indicia; and  
 a stationary multi-surface fold mirror having a first surface with a concave curvature positioned for collecting and reflecting the light reflected from the indicia for receipt by the photodetector, and at least a second beam shaping surface located substantially in a central region of the fold mirror and having a convex curvature for shaping the emitted laser beam, wherein the second beam shaping surface is positioned to reflect the emitted laser beam either as the beam passes from the light source to the scanning element or from the s g element to the indicia.  
 
     
     
       7. The arrangement of  claim 6 , wherein the light source is a laser diode. 
     
     
       8. The arrangement of  claim 6 , wherein the second beam shaping surface is larger in area than the first surface. 
     
     
       9. The arrangement of  claim 6 , wherein the convex curvature of the second beam shaping surface is cylindrical. 
     
     
       10. The arrangement of  claim 6 , wherein the second beam shaping surface is positioned to reflect the emitted laser beam as the beam passes from the light source to the scanning element. 
     
     
       11. The arrangement of  claim 6 , wherein the second beam shaping surface is positioned to reflect the emitted laser beam as the beam passes from the scanning element to the indicia.