Portable data collection device including imaging assembly with modular high density dataform reader assembly

• US 5,920,061 A
• Filed: 05/29/1997
• Issued: 07/06/1999
• Est. Priority Date: 05/29/1997
• Status: Expired due to Term

• Current Assignee: Symbol Technologies, LLC (Zebra Technologies Corporation)
• Original Assignee: Metanetics Corporation
• Inventors: Feng, Chen
• Primary Examiner(s): Hajec, Donald
• Assistant Examiner(s): Lee, Diane I.
• Application Number:
  US08/865,115
• Time in Patent Office: 768 Days
• Field of Search: 235/472.01, 235/462.42, 235/470, 235/454
• US Class Current: 235/472.01
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning

Abstract

A portable data collection device adapted to read high density bar code and matrix dataforms. The device includes an imaging assembly including a modular camera housing supporting a two dimensional (2D) photosensor array. The imaging assembly is selectively actuatable with a first trigger for reading a target dataform in the imaging assembly'"'"'s target area and actuatable with a second trigger for capturing a image of the target object in the target area. The modular camera housing precisely positions an optic assembly such that the sharpest image of the target dataform is focused at a center point of the photosensor array. The optic assembly includes a plurality of lenses supported in a shroud assembly. The shroud assembly is adjustable to permit precise positioning of the lens assembly with respect to the photosensor array along a longitudinal optical axis of the lens assembly. The shroud assembly is supported within the modular camera housing such that the optical axis of the lens assembly is perpendicular with respect to the photosensor array.

Claims

1. A portable data collection device comprising:

a) a modular camera assembly including a photosensor array having an array of photosensor elements generating a signal representative of an image of a target area;

b) a modular camera assembly housing for supporting components of the modular camera assembly;

c) an optic assembly including lens assembly supported within a shroud assembly and positioned to focus illumination reflected from a generally rectangular target area onto said photosensor elements, the optic assembly having a best focus position at a predetermined distance from an outwardly facing optic surface of an outermost lens which results in a clearest image of the target area being focused onto the photosensor elements;

d) an illumination assembly directing illumination towards the target area and including a lens array having a plurality of optic surfaces for directing illumination generated by illumination sources toward an area substantially congruent with the target area, the lens array forming an outer surface of the modular housing;

e) the shroud assembly supported within the housing and having an outwardly facing end adjacent the lens array; and

f) wherein the predetermined distance corresponding to the best focus position is less than four inches.

2. The portable data collection device of claim 1 wherein the outwardly facing end of the shroud assembly extends through an opening in the lens array.

3. The portable data collection device of claim 1 wherein the modular camera assembly housing is comprised of mating upper and lower portions which are identical in configuration, the modular camera housing defining an interior region and comprising an upper wall, a substantially parallel, spaced apart lower wall and a side wall between the upper and lower surfaces, the side wall including an opening in which the lens array is disposed.

4. The portable data collection device of claim 3 wherein the lens array is a thin, rectangular member is supported in a first narrow slot defined in interior surfaces of the upper wall, the lower wall and the side wall adjacent the side wall opening.

5. The portable data collection device of claim 4 wherein the illumination assembly includes a thin, rectangular illumination panel supporting the illumination sources and the panel is supported in a second narrow slot defined in the interior surfaces of the upper wall, the lower wall and the side wall, the second narrow slot being spaced from and substantially parallel to the first narrow slot.

6. The portable data collection device of claim 5 wherein the illumination panel includes an opening through which the shroud assembly extends.

7. The portable data collection device of claim 1 wherein the image of the target area includes a dataform in the target area and the device further includes image processing and decoder circuitry receiving the signal and generating decoded data representative of the dataform.

8. The portable data collection device of claim 7 wherein the dataform is a high density dataform.

9. A portable data collection device comprising:

a) a modular camera assembly including a photosensor array having an array of photosensor elements read out after an exposure period to generate a signal representative of an image of a target area;

b) a modular camera assembly housing for supporting components of the modular camera assembly;

c) an optic assembly including lens assembly supported within a shroud assembly and positioned to focus illumination reflected from a target area onto said photosensor elements, the optic assembly having a best focus position at a predetermined distance from an outwardly facing optic surface of an outermost lens which results in a clearest image of the target area being focused onto the photosensor elements;

d) an illumination assembly directing illumination towards the target area and including a lens array having a plurality of optic surfaces for directing illumination generated by illumination sources toward the target area, the lens array forming an outer surface of the modular housing;

e) the shroud assembly supported within the housing and having an outwardly facing end adjacent the lens array; and

f) wherein the shroud assembly includes an inner member and an outer member, the lens assembly being disposed within the inner member and the inner member being affixed to the outer member, the outer member supported on a support adapted to receive an end of the shroud outer member and align the lens assembly such that an optical axis of the lens assembly is substantially perpendicular to a light receiving surface of the photosensor array.

10. The portable data collection device of claim 9 wherein the photosensor array is mounted on a circuit board and the board is positioned in a slot defined in the housing inner surface and abuts the support.

11. The portable data collection device of claim 9 wherein the support encircles the end of the shroud outer member, the support and shroud outer member and support shielding the photosensor array from ambient light and permitting only light focused through the lens assembly to be directed onto the light receiving surface of the photosensor array.

12. The portable data collection device of claim 9 wherein the inner member is moveable with respect to the outer member along the optical axis of the lens assembly.

13. The portable data collection device of claim 12 herein an outer surface of the inner member threads into an inner surface of the outer member and the shroud assembly further includes a lock nut which threadedly engages the inner member as is positioned to precisely position the lens assembly a predetermined distance from the light receiving surface of the photosensor array.

14. A modular camera assembly for a portable data collection device for imaging a dataform in a target area of the camera assembly, the modular camera assembly comprising:

a) a modular camera housing defining an interior region in which components of the modular camera assembly are disposed and including a support extending into the interior region;

b) a board camera assembly including a two dimensional photosensor array comprising an array of photosensor elements which generate a signal representative of the target area, the photosensor array supported in a predetermined orientation within the housing;

c) an illumination assembly directing illumination towards the target area of the modular camera assembly and including a lens array having a plurality of optic surfaces for directing illumination generated by illumination sources toward an area substantially congruent with the target area, the lens array forming an outer surface of the modular housing;

d) an optic assembly including a lens assembly supported in a shroud assembly having an outwardly facing end directed toward the target area, the shroud assembly being at least partially supported by the support and oriented such that an optical axis of the lens assembly is substantially perpendicular to a light receiving surface of the photosensor array; and

e) wherein the optic assembly has a best focus position at a predetermined distance from an outwardly facing optic surface of an outermost lens of the lens assembly which results in a clearest image of the target area being focused onto the photosensor array photosensor elements, the predetermined distance corresponding to the best focus position being less than four inches.

15. The modular camera assembly of claim 14 wherein the outwardly facing end of the shroud assembly extends through an opening in the lens array.

16. The modular camera assembly of claim 14 wherein the modular camera assembly housing is comprised of mating upper and lower portions which are identical in configuration, the modular camera housing defining an interior region and comprising an upper wall, a substantially parallel, spaced apart lower wall and a side wall between the upper and lower surfaces, the side wall including an opening in which the lens array is disposed.

17. The modular camera assembly of claim 16 wherein the lens array is a thin, rectangular member is supported in a first narrow slot defined in interior surfaces of the upper wall, the lower wall and the side wall adjacent the side wall opening.

18. The modular camera assembly of claim 17 wherein the illumination assembly includes a thin, rectangular illumination panel supporting the illumination sources and the panel is supported in a second narrow slot defined in the interior surfaces of the upper wall, the lower wall and the side wall, the second narrow slot being spaced from and substantially parallel to the first narrow slot.

19. The modular camera assembly of claim 18 wherein the illumination panel includes an opening through which the shroud assembly extends.

20. The modular camera assembly of claim 14 wherein the dataform is a high density dataform.

21. A modular camera assembly for a portable data collection device for imaging a dataform in a target area of the camera assembly, the modular camera assembly comprising:

a) a modular camera housing defining an interior region in which components of the modular camera assembly are disposed;

b) a board camera assembly including a two dimensional photosensor array comprising an array of photosensor elements generating a signal representative of the target area, the photosensor array supported in a predetermined orientation within the housing;

c) an illumination assembly directing illumination towards the target area of the modular camera assembly and including a lens array having a plurality of optic surfaces for directing illumination generated by illumination sources toward the target area, the lens array forming an outer surface of the modular housing;

d) an optic assembly including a lens assembly supported in a shroud assembly, the shroud assembly being oriented such that an optical axis of the lens assembly is substantially perpendicular to a light receiving surface of the photosensor array; and

e) wherein the shroud assembly includes an inner member and an outer member, the lens assembly being disposed within the inner member and the inner member being affixed to the outer member, the outer member supported on a support extending into the interior region of the housing.

22. The modular camera assembly of claim 21 wherein the photosensor array is mounted on a circuit board and the board is positioned in a slot defined in the housing inner surface and abuts the support.

23. The modular camera assembly of claim 21 wherein the support encircles the end of the shroud outer member, the support and shroud outer member and support shielding the photosensor array from ambient light and permitting only light focused through the lens assembly to be directed onto the light receiving surface of the photosensor array.

24. The modular camera assembly of claim 21 wherein the shroud assembly inner member is moveable with respect to the outer member along the optical axis of the lens assembly.

25. The modular camera assembly of claim 24 wherein an outer surface of the inner member threads into an inner surface of the outer member and the shroud assembly further includes a lock nut which threadedly engages the inner member as is positioned to precisely position the lens assembly a predetermined distance from the light receiving surface of the photosensor array.