Hand-supported planar laser illumination and imaging (PLIIM) based systems with laser despeckling mechanisms integrated therein

• US 7,832,643 B2
• Filed: 10/30/2007
• Issued: 11/16/2010
• Est. Priority Date: 03/24/1998
• Status: Expired due to Fees

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: Schmidt, Mark C., Tassell, Jon Van, Zhu, Xiaoxun, Good, Timothy A., Knowles, C. Harry, Au, Ka Man, Ghosh, Sankar, Kolis, George, Colavito, Stephen J., Amundsen, Thomas, Vatan, Pirooz, Naylor, Charles A., Defoney, Shawn, Skypala, Edward, Schwartz, Barry E., Jankevics, Andrew, Schnee, Michael D., Wilz, David W. Sr., Blake, Robert, Tsikos, Constantine J., Giordano, Patrick A., Yorsz, Jeffery, Wirth, Allan, Kim, Steven Y., Dobbs, Russell Joseph, Svedas, William, Fisher, Dale
• Primary Examiner(s): LE, THIEN MINH
• Application Number:
  US11/980,081
• Publication Number:
  US 20080135621A1
• Time in Patent Office: 1,113 Days
• Field of Search: 23546201-46247, 235/472.01, 235/472.02, 235/472.03
• US Class Current: 235/462.25
• CPC Class Codes: G06K 7/10732 Light sources

Abstract

A hand-supportable planar laser illumination and imaging (PLIIM) based code symbol reader includes: a hand-supportable housing having light transmission aperture; a linear image formation and detection module having a linear image detection array; and a planar laser illumination beam (PLIB) producing device having at least one visible laser diode (VLD) for producing a planar light illumination beam (PLIB). The code symbol reader further includes image grabber for grabbing digital linear images formed and detected by the image formation and detection module, an image data buffer for buffering the digital linear images grabbed by the image grabber and constructing a two-dimensional image from a series of buffered linear digital images, and an image processing computer for processing the buffered two-dimensional digital image so as to read code symbols graphically represented in the two-dimensional digital linear image. During object illumination and imaging operations, a controller automatically controls the linear image formation and detection module, the PLIB producing device, the image frame grabber, and the image data buffer.

Claims

1. A hand-supportable planar laser illumination and imaging (PLIIM) based system comprising:

a hand-supportable housing having a light transmission aperture;

an image formation and detection module, disposed in said hand-supportable housing, and having an image detection array and image formation optics with a field of view (FOV) extending from said image detection array, through said light transmission aperture and onto an object moving relative to said hand-supportable housing during object illumination and imaging operations;

a planar laser illumination beam (PLIB) producing device, disposed in said hand-supportable housing, and having at least one visible laser illumination source arranged in relation to said image formation and detection module, for producing a planar laser illumination beam (PLIB), and projecting said PLIB through said light transmission aperture and oriented such that the plane of said PLIB is coplanar with the field of view of said image formation and detection module so that the object can be simultaneously illuminated by said PLIB and imaged within said field of view and onto said image detection array for detection as a digital linear image of the object;

a laser despeckling mechanism, disposed in said hand-supportable housing, for reducing the coherence of said PLIB during object illumination and imaging operations so that the power of speckle-pattern noise is substantially reduced in digital linear images detected on said image detection array;

an image grabber, disposed in said hand-supportable housing, for grabbing digital linear images formed and detected by said image formation and detection module;

an image data buffer, disposed in said hand-supportable housing, for buffering said digital linear images grabbed by said image grabber;

an image processor, disposed in said hand-supportable housing, and operably associated with said image data buffer, for processing said buffered digital linear images so as to read code symbols graphically represented in said digital linear images; and

a controller for automatically controlling one or more of said linear image formation and detection module, said PLIB producing device, said image frame grabber, said image data buffer and said image processor.

2. The hand-supportable PLIIM-based system of claim 1, wherein said PLIB producing device comprises beam forming optics disposed before each said visible laser illumination source so as to produce at least one PLIB component of said PLIB produced from said PLIB producing device.

3. The hand-supportable PLIIM-based system of claim 1, wherein said image forming optics have a fixed focal distance and a fixed focal length providing a fixed field of view.

4. The hand-supportable PLIIM-based system of claim 1, wherein said image forming optics have a variable focal distance and a fixed focal length providing a fixed field of view.

5. The hand-supportable PLIIM-based system of claim 1, wherein said image forming optics have a variable focal distance and a variable focal length providing a variable field of view.

6. The hand-supportable PLIIM-based system of claim 1, wherein code symbols are selected from the group consisting of bar code symbols.

7. The hand-supportable PLIIM-based system of claim 1, wherein said image formation and detection module, said PLIB producing device, said image frame grabber, said image data buffer and said controller are supported on a single platform within said hand-supportable housing.

8. The hand-supportable PLIIM-based system of claim 1, wherein said image data buffer comprises VRAM.

9. The hand-supportable PLIIM-based system of claim 1, wherein said image processor comprises a programmed microprocessor.

10. The hand-supportable PLIIM-based system of claim 1, wherein said controller comprises a programmed microprocessor.

11. The hand-supportable PLIIM-based system of claim 1, which further comprises a LCD display panel integrated with said hand-supportable housing, for displaying captured digital images of the object.

12. The hand-supportable PLIIM-based system of claim 11, which further comprises a manual data entry keypad integrated with said hand-supportable housing, for manually entering data into said hand-supportable PLIIM-based system during diverse types of information-related transactions supported by said hand-supportable PLIIM-based system.

13. The hand-supportable PLIIM-based system of claim 1, wherein said visible laser illumination source is a VLD.

14. The hand-supportable PLIIM-based system of claim 1, wherein said laser despeckling mechanism embodies an optical technique that effectively reduces the spatial and/or temporal coherence of said one or more laser illumination sources that are used to generate said PLIB.

15. The hand-supportable PLIIM-based system of claim 1, wherein said image detection array is a linear image detection array.

16. The hand-supportable PLIIM-based system of Claim 1, wherein code symbols are selected from the group consisting of 1D bar code symbols, 2D bar code symbols and matrix type bar code symbols.

17. The hand-supportable PLIIM-based system of claim 1, wherein said image detection array is a linear image detection array.

18. A hand-supportable planar laser illumination and imaging (PLIIM) based system comprising:

a hand-supportable housing having a light transmission aperture;

an image formation and detection module, disposed in said hand-supportable housing, and having an image detection array and image formation optics with a field of view (FOV) extending from said linear image detection array, through said light transmission aperture and onto an object moving relative to said hand-supportable housing during object illumination and imaging operations;

a planar laser illumination beam (PLIB) producing device, disposed in said hand-supportable housing, and having at least one visible laser illumination source arranged in relation to said linear image formation and detection module, for producing a planar laser illumination beam (PLIB), and projecting said PLIB through light transmission aperture and oriented such that the plane of said PLIB is coplanar with the field of view of said image formation and detection module so that the object can be simultaneously illuminated by said PLIB and imaged within said field of view and onto said linear image detection array for detection as a digital linear image of the imaged object;

a laser despeckling mechanism, disposed in said hand-supportable housing, for reducing the coherence of said PLIB during object illumination and imaging operations so that the power of speckle-pattern noise is substantially reduced in digital linear images detected on said linear image detection array;

an image grabber, disposed within said hand-supportable housing, for grabbing digital linear images formed and detected by said image formation and detection module;

an image data buffer, disposed en in said hand-supportable housing, for buffering said digital linear images grabbed by said image grabber, and constructing a two-dimensional image of the object from a series of buffered digital linear images thereof;

an image processor, disposed in said hand-supportable housing, and operably associated with said image data buffer, for processing said buffered digital linear images so as to read code symbols graphically represented in said two-dimensional digital image; and

a controller for automatically controlling one or more of said image formation and detection module, said PLIB producing device, said image frame grabber, and said image data buffer.

19. The hand-supportable PLIIM-based system of claim 18, wherein said PLIB producing device comprises beam forming optics disposed before each said visible illumination source so as to produce at least one PLIB component of said PLIB produced from said PLIB producing device.

20. The hand-supportable PLIIM-based system of claim 18, wherein said image forming optics have a fixed focal distance and a fixed focal length providing a fixed field of view.

21. The hand-supportable PLIIM-based system of claim 18, wherein said image forming optics have a variable focal distance and a fixed focal length providing a fixed field of view.

22. The hand-supportable PLIIM-based system of claim 18, wherein said image forming optics have a variable focal distance and a variable focal length providing a variable field of view.

23. The hand-supportable PLIIM-based system of claim 18, wherein said image formation and detection module, said PLIB producing device, said image frame grabber, said image data buffer and said controller are supported on a single platform within said hand-supportable housing.

24. The hand-supportable PLIIM-based system of claim 18, wherein said image data buffer comprises VRAM.

25. The hand-supportable PLIIM-based system of claim 18, wherein said image processor comprises a programmed microprocessor.

26. The hand-supportable PLIIM-based system of claim 18, wherein said controller comprises a programmed microprocessor.

27. The hand-supportable PLIIM-based system of claim 18, wherein said visible laser illumination source is a VLD.

28. The hand-supportable PLIIM-based system of claim 18, which further a manual data entry keypad integrated with said hand-supportable housing, for manually entering data into said hand-supportable PLIIM-based system during diverse types of information-related transactions supported by said hand-supportable PLIIM-based system.

29. The hand-supportable PLIIM-based system of claim 18, wherein said laser despeckling mechanism embodies an optical technique that effectively reduces the spatial and/or temporal coherence of said one or more laser illumination sources that are used to generate said PLIB.