Method and apparatus for non-contact reading of a relief pattern

A non-contact apparatus for reading a surface that has information encoded in a relief pattern thereon, the relief pattern having relatively raised and recessed portions and transitions therebetween, the recessed portions having bottom surfaces being aligned in a lengthwise direction, said apparatus comprising:

• optical transmitter means for projecting a line of light onto the raised portions of the relief pattern and onto the bottom surfaces of the recessed portions of the relief pattern at a first angle to a normal of the surface;
• optical receiver means for viewing said projected line of light on the relief pattern at a second angle to the normal of the surface and for producing signal data that is representative of an image of a reflection of said line of sight whereby said image includes a parallactic displacement of said projected line at a transition between a raised portion and the bottom surface of a recessed portion of the relief pattern therealong;
• means for culling, said signal data received by said receiver means so that only those pixels substantially constituting the image of the line of light are selected;
• means for decoding said culled signal data into electrical signals which represent decoded information contained in the relief pattern;
• said optical transmitter means, said optical receiver means, said means for culling and said means for decoding are contained within a portable handheld unit;
• and
• said optical transmitter means and said optical receiver means being at opposite ends of a hand grip of said hand held unit.

A non-contact apparatus for reading a surface that has information encoded in a relief pattern thereon, said relief pattern having a relatively raised portion and a relatively recessed portion and a transition therebetween, said recessed portion having a bottom surface aligned in a lengthwise direction, said apparatus comprising:

• an optical transmitter effective for projecting a line of light onto said raised portion of said relief pattern and onto said bottom surface of said recessed portion of said relief pattern at a first angle to a normal of said surface;
• an optical receiver effective for viewing said projected line of light on said relief pattern at a second angle to said normal of said surface;
• said optical receiver producing a plurality of pixels representative of an image of a reflection of said line of sight wherein said image includes a parallactic displacement of said projected line at a transition between said raised portion and said bottom surface of said recessed portion;
• a data culling circuit wherein only those pixels substantially constituting the image of the reflection of said line of light are selected, thereby producing culled signal data whereby said culling means culls within said line by detecting said pixels that exceeds an estimate of a level of background information;
• and
• a decoder effective for decoding said culled signal data into electrical signals which represent decoded information contained in said relief pattern.

A hand-held apparatus for reading a relief pattern on a surface, comprising:

• a hand-held housing having first and second ends separated by a hand grip;
• optical transmitter means, mounted in said first end, for projecting a line of light onto the surface;
• optical receiver means, mounted in said second end, for receiving an image reflected from said surface;
• said image including an image of said line of light;
• conversion means for converting said image to a plurality of pixels;
• culling means, mounted in said hand-held housing, for culling said plurality of pixels such that only those pixels substantially constituting said image of said line of light are selected;
• and
• means for decoding said culled plurality of pixels into electrical signals representing decoded information contained in the relief pattern.