Illumination system with white level calibration for hand-held scanner

An illumination system for illuminating a scan region on an object and for providing a white level reference for a detector, comprising:

• a light source for producing a plurality of light rays;
• an elongate lens member having a first end and a second end, said elongate lens member being positioned between said light source and the scan region, said elongate lens member collecting some of the light rays from said light source and directing the collected light rays onto the scan region;
• a first spot lens positioned adjacent the first end of said elongate lens member and said light source so that some of the plurality of light rays from said light source are collected by said first spot lens and directed onto the scan region;
• a second spot lens positioned adjacent the second end of said elongate lens member and said light source so that some of the plurality of light rays from said light source are collected by said second spot lens and directed onto the scan region;
• a first white level reference mark positioned adjacent said first spot lens and said light source so that some of the plurality of light rays from said light source are reflected by said first white level reference mark to the detector.

Scanner apparatus for scanning a scan region on an object, comprising:

• a light source for producing a plurality of light rays;
• an elongate lens having a first end and a second end, said elongate lens being positioned adjacent said light source, said elongate lens collecting some of the light rays from said light source and directing them onto the scan region, wherein the scan region comprises an elongate scan line having a first end and a second end;
• a first spot lens positioned adjacent the first end of said elongate lens member;
• a second spot lens positioned adjacent the second end of said elongate lens member, said first and second spot lenses also being positioned adjacent said light source so that some of the light rays from said light source are directed toward the first and second ends of the elongate scan line by said first and second spot lenses, respectively;
• a detector for producing output signals relating to light incident thereon;
• an optical system for collecting image light reflected by the scan region and focusing the image light onto said detector;
• a first white level reference mark positioned adjacent said lens and said light source so that some of the plurality of light rays from said light source are reflected by said first white level reference mark to said optical system, said optical system collecting the reflected light rays from said first white level reference mark and focusing the reflected light rays from said first white level reference mark onto said detector;
• and
• image processing apparatus connected to said detector and responsive to the output signals produced by said detector, said image processing apparatus producing image data signals.

An illumination system for illuminating a scan region on an object and for providing a white level reference for a detector, comprising:

• a light source for producing a plurality of light rays;
• an elongate lens having a first end and a second end, said elongate lens being positioned between said light source and the scan region, said lens collecting some of the light rays from said light source and directing the collected light rays onto the scan region;
• a first white level reference mark positioned adjacent the first end of said lens;
• and
• a second white level reference mark positioned adjacent the second end of said lens, said first and second white level reference marks reflecting to the detector some of the light rays from said light source.