Scan line illumination system utilizing hollow reflector

• US 6,229,137 B1
• Filed: 09/14/1998
• Issued: 05/08/2001
• Est. Priority Date: 09/14/1998
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Bohn, David D.
• Primary Examiner(s): LEE, JOHN R
• Application Number:
  US09/152,966
• Time in Patent Office: 967 Days
• Field of Search: 250/234, 250/235, 250/236, 250/216, 250/228, 362/31, 362/558, 362/551, 362/291, 362/296, 362/304, 362/305, 362/307, 362/310, 362/311, 358/474, 358/475, 358/484, 358/509, 358/510
• US Class Current: 250/234
• CPC Class Codes: H04N 1/02815 Means for illuminating the original, not specific to a particular type of pick-up head
• CPC Class Codes: H04N 1/0285 in combination with at least one reflector which is in fixed relation to the light source
• CPC Class Codes: H04N 1/0286 in combination with a light integrating, concentrating or defusing cavity
• CPC Class Codes: H04N 1/02865 using an array of light sources or a combination of such arrays, e.g. an LED bar
• CPC Class Codes: H04N 1/0318 Integral pick-up heads, i.e. self-contained heads whose basic elements are a light-source, a lens array and a photodetector array which are supported by a single-piece frame
• CPC Class Codes: H04N 2201/03112 Light source
• CPC Class Codes: H04N 2201/03116 Light source lens
• CPC Class Codes: H04N 2201/03141 Photodetector lens
• CPC Class Codes: H04N 2201/03145 Photodetector

Abstract

An illumination system for illuminating a scan region on an object may comprise a hollow reflector having an interior reflective surface, an entrance aperture, and an exit aperture. A light source is positioned adjacent the entrance aperture of the hollow reflector so that some of the light rays produced by the light source pass through the entrance aperture and are reflected by the interior reflective surface of the hollow reflector before passing through the exit aperture.

Claims

1. An illumination system for illuminating a scan region on an object, comprising:

a hollow reflector having an interior reflective surface, an entrance aperture, and an exit aperture;

a light source for producing a plurality of light rays, said light source being positioned adjacent the entrance aperture of said hollow reflector so that some of the light rays produced by said light source pass through the entrance aperture and are reflected by the interior reflective surface of said hollow reflector before passing through the exit aperture, the light rays passing through the exit aperture illuminating the scan region on the object.

2. The illumination system of claim 1, further comprising a lens positioned adjacent the exit aperture of said hollow reflector for concentrating light rays passing through the exit aperture of said hollow reflector.

3. The illumination system of claim 2, wherein said hollow reflector comprises a generally cylindrically shaped member having a sidewall that defines the interior reflective surface and wherein the entrance aperture comprises a generally elongate axial opening in the sidewall located at a first radial position on the sidewall and wherein the exit aperture comprises a generally elongate axial opening in the sidewall located at a second radial position on the sidewall.

4. The illumination system of claim 3, wherein the interior reflective surface of the sidewall is coated with a diffusing reflecting material.

5. The illumination system of claim 4, wherein said lens comprises a cylindrical lens.

6. The illumination system of claim 5, wherein said light source comprises a plurality of light emitting diodes.

7. An illumination system for illuminating a scan region on an object, comprising:

a hollow reflector having an interior reflective surface, an entrance aperture, and an exit aperture;

a light source for producing a plurality of light rays, said light source being positioned within the entrance aperture of said hollow reflector so that substantially all of the light rays produced by said light source enter said hollow reflector and are reflected by the interior reflective surface of said hollow reflector before passing through the exit aperture, the light rays passing through the exit aperture illuminating the scan region on the object.

8. The illumination system of claim 7, further comprising a lens positioned adjacent the exit aperture of said hollow reflector for concentrating light rays passing through the exit aperture of said hollow reflector.

9. The illumination system of claim 8, wherein said hollow reflector comprises a generally cylindrically shaped member having a sidewall that defines the interior reflective surface and wherein the entrance aperture comprises a generally elongate axial opening in the sidewall located at a first radial position on the sidewall and wherein the exit aperture comprises a generally elongate axial opening in the sidewall located at a second radial position on the sidewall.

10. The illumination system of claim 9, wherein the interior reflective surface of the sidewall is coated with a diffusing reflecting material.

11. The illumination system of claim 10, wherein said lens comprises a cylindrical lens.

12. The illumination system of claim 11, wherein said light source comprises a plurality of light emitting diodes.

13. An illumination system for illuminating a scan region on an object, comprising:

an elongate, generally cylindrically shaped member having a side wall that defines an interior reflective surface, said sidewall having an entrance aperture therein comprising a first generally elongate axial opening located at a first radial position on the sidewall and an exit aperture therein comprising a second generally elongate axial opening located at a second radial position;

a light source for producing a plurality of light rays, said light source being positioned adjacent the first generally elongate opening so that some of the plurality of light rays produced by said light source pass through the entrance aperture; and

a lens positioned adjacent the second generally elongate opening, said lens concentrating light rays passing through the exit aperture.

14. An illumination system for illuminating a scan region on an object, comprising:

an elongate, generally cylindrically shaped member having a side wall that defines an interior reflective surface, said sidewall having an entrance aperture therein comprising a first generally elongate axial opening located at a first radial position on the sidewall and an exit aperture therein comprising a second generally elongate axial opening located at a second radial position;

a light source for producing a plurality of light rays, said light source being positioned within the first generally elongate opening so that substantially all of the plurality of light rays produced by said light source enter said elongate, generally cylindrically shaped member; and

a lens positioned adjacent the second generally elongate opening, said lens concentrating light rays passing through the exit aperture.

15. An illumination system for illuminating a scan region on an object, comprising:

hollow reflector means having an interior reflective surface, an entrance aperture, and an exit aperture;

light source means for producing a plurality of light rays, said light source means being positioned adjacent the entrance aperture of said hollow reflector means so that some of the light rays produced by said light source means pass through the entrance aperture and are reflected by the interior reflective surface of said hollow reflector means before passing through the exit aperture, the light rays passing through the exit aperture illuminating the scan region on the object.

16. A method for illuminating a scan region on an object, comprising:

providing a hollow reflector having an interior reflecting surface and an exit aperture; and

directing a plurality of light rays onto the interior reflecting surface of the hollow reflector, the interior reflecting surface reflecting some of the light rays through the exit aperture in the hollow reflector.

17. Scanner apparatus, comprising:

a main body;

an image sensing system mounted within said main body for sensing image light reflected by an illuminated scan region;

a hollow reflector mounted within said main body, said hollow reflector having an interior reflective surface, an entrance aperture, and an exit aperture;

a light source for producing a plurality of light rays, said light source being positioned within the entrance aperture of said hollow reflector so that substantially all of the light rays produced by said light source enter said hollow reflector and are reflected by the interior reflective surface of said hollow reflector before passing through the exit aperture, the light rays passing through the exit aperture illuminating the scan region.