Axially invariant pattern scanning apparatus

In a scanning system having a spin axis along which light beams are projected for scanning coded indicia and then reflected from the scanned coded indicia, means for generating a scan pattern comprising;

• means for projecting scanning light along said spin axis;
• a deflector element mounted in said spin axis including a first reflecting surface for deflecting the light beams projected along said spin axis in a direction generally perpendicular to the spin axis and a second reflecting surface for deflecting the scanning light beams in a direction parallel to a spin axis;
• and
• a plurality of reflecting elements mounted around said deflector means, said reflecting elements deflecting the light beams reflected from the first reflecting surface towards the second reflecting surface whereby the second deflecting surface will deflect the scanning light beams in a direction along said spin axis for forming a scan pattern whose center will remain constant as the distance between the second deflecting surface and the bar code label changes.

In a scanning system having a spin axis along which light beams are projected for scanning a coded indicia, means for forming a scan pattern comprising:

• a rotating hollow drive shaft mounted on said spin axis;
• a source of scanning light beams positioned at one end of said shaft for projecting the light beams along said spin axis;
• deflector means secured to the other end of said drive shaft;
• said deflector means including a first reflecting surface extending across the spin axis for deflecting the scanning light beams along a first light path extending in an outward direction from said spin axis and a second reflecting surface extending across said spin axis and positioned downstream of said first reflecting surface;
• and
• a ring of reflecting mirror members mounted around said deflector means and in said first light path for deflecting the received scanning light beams along a second light path towards the second reflecting surface which reflects the scanning light beams along said spin axis in the form of a scan pattern whose center will remain the same as the distance between the second reflecting surface and the bar code label changes.