Abstract:
A method of and a system for generating a dense pattern of scan lines. In a preferred configuration, a laser beam is directed into an inline beam dithering mechanism which dithers the beam over an angle parallel to the axis of rotation of the rotating facet wheel. The combination of the dithering mechanism and the scanning motion of the rotating facet wheel creates a dense scan pattern. Return light is retrodirectively collected by a collection element such as a collection lens onto a detector. A beam redirector such as a cone-shaped device having openings on both ends and a reflecting internal surface is disposed between the collection lens and the detector to redirect off-axis spot onto the detector. The system and method is applicable to both single and multiple beam systems and single and multiple window scanners.
Abstract:
Methods are disclosed for triggering a source of visible light in connection with a data reader in response to a sensed proximity of an item. In one configuration, a data reader includes an imaging reader, such as a CMOS imager, that is sensitive to both infrared illumination and visible light. The imaging reader may be operable to read a symbol, such as a barcode or other optical code, via reflected infrared illumination, reflected visible light, or both. When characteristics of reflected illumination received by the imaging reader indicate the presence or movement of an item in the visible scan zone, the visible light source may be triggered to illuminate the item and thereby facilitate reading of the symbol using the same imaging reader as is used to sense the presence of the item. The visible light source may also be triggered to provide visual feedback.