Barcode scanners are well known for their usefulness in retail checkout and inventory control. They typically include a laser diode, a mirrored spinner, a plurality of pattern mirrors, a collector, and a detector. In particular, the function of the pattern mirrors is to direct scanning beams from the mirrored spinner out of the scanner to form a scan pattern. Furthermore, the pattern mirrors direct light reflected from an item bearing a barcode label to the mirrored spinner.
In some applications, it is important to reduce size of barcode scanners without decreasing performance.
A barcode scanner including a multi-tasking pattern mirror is provided.
The bar code scanner includes a laser for producing a laser beam, a mirrored spinner for reflecting the laser beam, and a plurality of pattern mirrors for directing the laser beam from the mirrored spinner to produce a scan pattern and for directing light reflected from an item to the mirrored spinner. One of the pattern mirrors is located between the laser and the mirrored spinner and includes an aperture for allowing the laser beam to pass through. The one pattern mirror may also serve to direct the reflected light from the mirrored spinner to the collector.
Referring now to
Laser 12 produces a laser beam 36. Laser 12 directs laser beam 36 towards mirrored spinner 16.
Pattern mirrors 14 direct laser beam 36 from mirrored spinner 16 to produce scan lines for scanning barcode 42 on item 40. Pattern mirrors 14 also direct light reflected from item 40 to mirrored spinner 16.
Pattern mirrors 14 include primary pattern mirrors 24 and secondary pattern mirrors 26. Primary pattern mirrors 24 direct the light beam from mirrored spinner 16 to secondary pattern mirrors 24. Secondary pattern mirrors 26 direct the light beam from primary pattern mirror 24 to scan item 40, and direct light reflected from item 40 to primary pattern mirrors 24. Primary pattern mirrors 24 further direct the reflected light to mirrored spinner 16.
Primary pattern mirrors 24 include multi-tasking pattern mirror 28. Multi-tasking pattern mirror 28 includes aperture 30. Laser beam 36 from laser 12 passes through aperture 30 on its way to mirrored spinner 16.
Multi-tasking pattern mirror 28 also functions to direct light reflected from item 40 from spinner 16 towards collector 18.
Mirrored spinner 16 sweeps laser beam 36 across primary pattern mirrors 24. Mirrored spinner 16 also receives the reflected light from primary pattern mirrors 14. Mirrored spinner 16 directs the reflected light towards multi-tasking pattern mirror 28. Mirrored spinner 16 is rotated by motor 34.
Collector 18 collects light reflected from item 40 from multi-tasking pattern mirror 28. Collector 18 directs the reflected light towards detector 20.
Detector 20 converts the reflected light into electrical signals containing information representative of barcode label 42.
Turning now to
In addition to multi-tasking pattern mirror 28, primary pattern mirrors 24 include pattern mirrors 60a and 62a to one side of multi-tasking pattern mirror 28, and pattern mirrors 60b and 62b to the other side of multi-tasking pattern 28.
With reference to
The optical design of scanner 10, including the use of multi-tasking pattern mirror 28, facilitates a reduction in size of housing 50 from conventional designs, particularly a reduction in depth D and length L. The reduction may be as much as 50% in depth D and length L.
A further advantage is that optical scanner 10 produces 50% more lines and line length compared to other single window scanners.
Laser beam 36 passes from one side of multi-tasking pattern mirror 28 to another through aperture 30 and strikes mirrored spinner 16. Without aperture 30, primary pattern mirrors 24 would have to be located farther from mirrored spinner 16 to avoid obstructing laser beam 36 on its way to mirrored spinner 16, thereby increasing the depth D and length L of scanner 10.
Mirrored spinner 16 sweeps laser beam 36 across primary pattern mirrors 60a, 62a, 28, 62b, and 60b. In an example embodiment, mirrored spinner 16 includes five facets 38. Each facet 38 is oriented at a slightly different angle in order to shift each scan line between five different positions in the scan volume above window 52.
Secondary pattern mirror 64a receives laser beam 36 from multi-tasking pattern mirror 28 and pattern mirrors 60a and 62a. Secondary pattern mirror 64b receives laser beam 36 from multi-tasking pattern mirror 28 and pattern mirrors 60b and 62b.
With reference to
Primary pattern mirrors 60a, 62a, 28, 62b, and 60b direct the reflected light to mirrored spinner 16. Mirrored spinner directs the reflected light towards laser 12 where multi-tasking pattern mirror 28 intercepts the reflected light and directs it towards collector 18.
Collector 18 directs the reflected light towards detector 20. Collector 18 is located in a position to collect the reflected light without interfering with outgoing laser beam 36.
With reference to
Although particular reference has been made to certain embodiments, variations and modifications are also envisioned within the spirit and scope of the following claims.