Arrangement for and method of reducing vertical parallax between an aiming pattern and an imaging field of view in a linear imaging reader

• US 8,534,556 B2
• Filed: 10/26/2010
• Issued: 09/17/2013
• Est. Priority Date: 10/26/2010
• Status: Active Grant

• Current Assignee: Symbol Technologies, LLC (Zebra Technologies Corporation)
• Original Assignee: Symbol Technologies, Inc. (Zebra Technologies Corporation)
• Inventors: Drzymala, Mark, Barkan, Edward
• Primary Examiner(s): MARSHALL, CHRISTLE I
• Application Number:
  US12/911,974
• Publication Number:
  US 20120097744A1
• Time in Patent Office: 1,057 Days
• Field of Search: None
• US Class Current: 235/454
• CPC Class Codes: G06K 2207/1011 Aiming
• CPC Class Codes: G06K 7/10732 Light sources
• CPC Class Codes: G06K 7/10831 Arrangement of optical elements, e.g. lenses, mirrors, prisms optical elements per se G02B

Abstract

Vertical parallax between an imaging linear field of view (FOV) and an aiming light pattern is reduced in a reader for electro-optically reading symbols to be read by image capture by an arrangement that includes an imaging assembly having a solid-state imager with a linear array of image sensors, and an imaging lens for capturing return light over the imaging linear FOV from a symbol and for projecting the captured return light onto the linear array, an aiming light assembly spaced vertically away from the imaging assembly for generating the aiming light pattern on the symbol prior to reading, and an optical assembly for intercepting the aiming light pattern and for vertically aligning the aiming light pattern with the imaging linear FOV to reduce the vertical parallax.

Claims

1. In a reader for electro-optically reading symbols to be read by image capture, an arrangement for reducing vertical parallax between an imaging linear field of view (FOV) and an aiming light pattern, the arrangement comprising:

an imaging assembly mounted on a tilted printed circuit board (PCB) within a tilted handle of the reader including a solid-state imager having a linear array of image sensors, and an imaging lens system for capturing return light over the imaging linear FOV from a symbol and for projecting the captured return light onto the linear array, the imaging linear FOV extending predominantly in a horizontal direction, wherein the PCB and the handle are tilted relative to the vertical;

an aiming light assembly spaced vertically away from the imaging assembly on the tilted PCB within the tilted handle of the reader, for generating the aiming light pattern on the symbol prior to reading; and

an optical assembly for intercepting the aiming light pattern and for vertically aligning the aiming light pattern with the imaging linear FOV substantially on a same horizontal plane that is parallel to both the horizontal direction and a principle propagation direction of the aiming light pattern to reduce the vertical parallax.

2. The arrangement of claim 1, wherein the imager is one of a one-dimensional charge coupled device and a one-dimensional complementary metal oxide silicon device.

3. The arrangement of claim 1, wherein the aiming light assembly includes an aiming light source for emitting an aiming light beam, and an aiming lens for optically modifying the aiming light beam to project the aiming pattern on the symbol.

4. The arrangement of claim 3, wherein the aiming light source is a laser for emitting an aiming laser beam, and wherein the aiming lens is operative for optically modifying the aiming laser beam to project the aiming pattern on the symbol as one of a generally circular aiming spot, a cross-hairs, a plurality of generally circular aiming spots, and an aiming line.

5. The arrangement of claim 1, wherein the imager is mounted at a lower elevation on the tilted PCB, and wherein the aiming light assembly is located above the imager and is mounted at least in part at a higher elevation on the same PCB.

6. The arrangement of claim 5, wherein the optical assembly includes an upper fold mirror at the higher elevation, and a lower fold mirror at the lower elevation, and wherein the upper fold mirror redirects the intercepted aiming light pattern to the lower fold mirror.

7. The arrangement of claim 1, and further comprising a handheld housing in which the assemblies are mounted.

8. The arrangement of claim 1, and further comprising an illumination light assembly for illuminating the symbol, and including a pair of illumination light emitting diodes (LEDs) spaced apart from each other, and a pair of illumination lenses, one for each illumination LED.

9. The arrangement of claim 8, wherein the illumination LEDs are located at opposite sides of the imager on the same PCB.

10. An imaging reader for electro-optically reading symbols by image capture, comprising:

a housing with a tilted handle;

a tilted printed circuit board (PCB) mounted in the tilted handle of the housing, wherein the PCB and the handle are tilted relative to the vertical; and

an imaging module mounted on the tilted PCB within the tilted handle including

an imaging assembly having a solid-state imager with a linear array of image sensors mounted on the PCB, and an imaging lens for capturing return light over an imaging linear field of view (FOV) from a symbol and for projecting the captured return light onto the linear array, the imaging linear FOV extending predominantly in a horizontal direction,

an aiming light assembly mounted at least in part on the PCB and spaced vertically away from the imaging assembly on the tilted PCB within the tilted handle, for generating an aiming light pattern on the symbol prior to reading, and

an optical assembly for intercepting the aiming light pattern and for vertically aligning the aiming light pattern with the imaging linear FOV substantially on a same horizontal plane that is parallel to both the horizontal direction and a principle propagation direction of the aiming light pattern to reduce vertical parallax between the aiming light pattern and the imaging linear FOV.

11. A method of reducing vertical parallax between an imaging linear field of view (FOV) and an aiming light pattern in a reader for electro-optically reading symbols to be read by image capture, comprising the steps of:

capturing return light over the imaging linear FOV from a symbol, and projecting the captured return light onto a linear array of image sensors of a solid-state imager mounted on a tilted printed circuit board within a tilted handle of the reader, the imaging linear FOV extending predominantly in a horizontal direction, wherein the PCB and the handle are tilted relative to the vertical;

generating the aiming light pattern on the symbol prior to reading with an aiming light assembly spaced vertically away from the imager on the tilted PCB within the tilted handle of the reader; and

intercepting the aiming light pattern, and vertically aligning the aiming light pattern with the imaging linear FOV substantially on a same horizontal plane that is parallel to both the horizontal direction and a principle propagation direction of the aiming light pattern to reduce the vertical parallax.

12. The method of claim 11, and further comprising the step of configuring the imager as one of a one-dimensional charge coupled device and a one-dimensional complementary metal oxide silicon device.

13. The method of claim 11, wherein the generating step is performed by an aiming light source that emits an aiming light beam, and by an aiming lens that optically modifies the aiming light beam to project the aiming pattern on the symbol.

14. The method of claim 13, and further comprising the step of configuring the aiming light source as a laser that emits an aiming laser beam, and wherein the aiming lens optically modifies the aiming laser beam to project the aiming pattern on the symbol as one of a generally circular aiming spot, a cross-hairs, a plurality of generally circular aiming spots, and an aiming line.

15. The method of claim 11, and further comprising the step of mounting the imager at a lower elevation on the tilted PCB, and mounting the aiming light assembly at least in part above the imager at a higher elevation on the same PCB.

16. The method of claim 15, wherein the intercepting and aligning steps are performed by an upper fold mirror at the higher elevation, and by a lower fold mirror at the lower elevation, and wherein the upper fold mirror redirects the intercepted aiming light pattern to the lower fold mirror.

17. The method of claim 11, and further comprising the step of illuminating the symbol with a pair of illumination light emitting diodes (LEDs) spaced apart from each other, and with a pair of illumination lenses, one for each illumination LED.

18. The method of claim 17, and further comprising the step of mounting the illumination LEDs at opposite sides of the imager on the same PCB.