Method and apparatus for illumination and imaging of a surface using 2-D LED array

• US 5,408,084 A
• Filed: 02/18/1993
• Issued: 04/18/1995
• Est. Priority Date: 02/18/1993
• Status: Expired due to Term

• Current Assignee: Gn Nettest, United Parcel Service Of America Incorporated (United Parcel Service Incorporated)
• Original Assignee: United Parcel Service Of America Incorporated (United Parcel Service Incorporated)
• Inventors: Sussmeier, John W., Brandorff, Alexander
• Primary Examiner(s): Nelms, David C.
• Assistant Examiner(s): Allen, Stephone B.
• Application Number:
  US08/019,220
• Time in Patent Office: 789 Days
• Field of Search: 250/208.1, 250/227.13, 250/552, 250/553, 250/557, 250/559, 250/571, 250/566-568, 235/462, 235/472, 235/473, 358/473, 358/482
• US Class Current: 250/208.1
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10732 Light sources
• CPC Class Codes: G06K 7/1092 sensing by means of TV-scanning

Abstract

An apparatus for illuminating and imaging a surface includes a two-dimensional array of LEDs for providing uniform illumination to the surface, the LEDs being mounted on a planar surface with a centrally defined aperture, and a CCD-based camera with appropriate lensing for obtaining an image of the illuminated surface and providing a signal representative of that obtained image to a processing unit, the CCD-based camera lensing being disposed through the centrally defined aperture in the planar surface of the LED array, and the LED array and CCD-camera lensing being disposed inside an opaque shroud.

Claims

1. An illumination and imaging apparatus, comprising:

(a) a two-dimensional array of LEDs for illuminating a surface;

(b) means for obtaining an image of the illuminated surface and providing an output signal representative of said obtained image; and

(c) a handle, said LED array and said image obtaining means being mounted on said handle for positioning by hand;

wherein said array is supported on a planar surface, an aperture being defined centrally through said planar surface.

2. The apparatus of claim 1, wherein said image obtaining means is a CCD-based camera.

3. The apparatus of claim 1, wherein said image obtaining means is a CCD-based camera having lensing, said lensing being disposed through the aperture defined in said planar surface.

4. The apparatus of claim 1, wherein said LEDs are mounted on said planar surface in a series of horizontal rows, with equal spacing between said LEDs within each said horizontal row, and said horizontal rows being equally spaced from one another.

5. The apparatus of claim 4, wherein each said horizontal row is offset by half the center-to-center spacing of said LEDs in the preceding and succeeding horizontal rows.

6. An illumination and imaging apparatus, comprising:

(a) a two-dimensional array of LEDs for illuminating a surface;

(b) means for obtaining an image of the illuminated surface and providing an output signal representative of said obtained image, said image obtaining means comprising lensing;

(c) a generally sleeve-like shroud having a generally vertical opaque wall, defining a lower opening;

said array and said lensing being mounted inside an upper portion of said shroud.

7. The apparatus of claim 6, wherein said lower opening is defined by a lower edge of said vertical shroud wall, said edge lying substantially in a plane.

8. The apparatus of claim 6, wherein substantially all of the interior surface of said shroud below said array is reflective of light emitted by said array.

9. A method for illuminating and imaging a target surface, comprising the steps of:

(a) manually positioning a two-dimensional array of LEDs in a selected position with respect to the target surface, said array being supported on a planar surface with a centrally defined aperture disposed therethrough;

(b) illuminating the target surface by use of said two-dimensional array of LEDs; and

(c) obtaining an image of the illuminated target surface and providing an output signal representative of the obtained image.

10. The method of claim 9, wherein said step of image obtaining comprises using a CCD-based camera.

11. The method of claim 10, wherein said LEDs are mounted on said planar surface in a series of horizontal rows, with equal spacing between said LEDs within each said horizontal row, and said horizontal rows being equally spaced from one another.

12. The method of claim 11, wherein each said horizontal row is offset by half the center-to-center spacing of said LEDs in the preceding and succeeding horizontal rows.

13. The method of claim 9, wherein said step of image obtaining comprises using a CCD-based camera, and wherein said CCD-based camera has lensing, said lensing being disposed through said aperture in said planar surface to a predetermined position with respect to the surface.

14. A method for illuminating and imaging a target surface, comprising the steps of:

(a) providing a two-dimensional array of LEDs and camera lensing inside the upper portion of a generally sleeve-like shroud having a generally vertical opaque wall, the lower edge of said generally vertical opaque wall defining a lower opening, said edge lying substantially in a plane;

(b) illuminating the target surface by use of said LED array; and

(c) obtaining an image of the illuminated target surface, employing said lensing, and providing an output signal representative of the obtained image.

15. The method of claim 14, further comprising the step of manually placing said edge in contact with the target surface and maintaining said edge in contact with the target surface during said steps (b) and (c).