Method and System for Filtering an Optical Lens

• US 20080296381A1
• Filed: 05/30/2007
• Published: 12/04/2008
• Est. Priority Date: 05/30/2007
• Status: Abandoned Application

• Current Assignee: Symbol Technologies, Inc. (Zebra Technologies Corporation)
• Original Assignee: Symbol Technologies, Inc. (Zebra Technologies Corporation)
• Inventors: Shi, David Tsi, YU, Ming
• Application Number:
  US11/755,541
• Publication Number:
  US 20080296381A1
• Time in Patent Office: Days
• US Class Current: 235/462.01
• CPC Class Codes: G06K 7/10544 by scanning of the records by radiation in the optical part of the electromagnetic spectrum
• CPC Class Codes: G06K 7/10831 Arrangement of optical elements, e.g. lenses, mirrors, prisms optical elements per se G02B
• CPC Class Codes: G06K 7/12 using a selected wavelength, e.g. to sense red marks and ignore blue marks

Abstract

Described are a method and system for filtering an optical lens. The system includes an imager providing an image of a target based on light from the target; an optical lens having a light-filtering coating blocking ambient light, the optical lens focusing at least a portion of the light from the target onto the imager; and a processing device decoding the image of the target.

Claims

1. A system, comprising:

an imager providing an image of a target based on light from the target;

an optical lens having a light-filtering coating blocking ambient light, the optical lens focusing at least a portion of the light from the target onto the imager; and

a processing device decoding the image of the target.

2. The system according to claim 1, further comprising:

an illumination element transmitting light to the target, the target including light-activated ink activated by the illumination element.

3. The system according to claim 1, wherein the illumination element is an ultra-violet (“

UV”

) light emitting diode (“

LED”

).

4. The system according to claim 1, wherein the target is a barcode symbol printed using a fluorescent ink, the target emitting a fluorescent light upon being activated, the fluorescent light having a wavelength within a predetermined range.

5. The system according to claim 1, wherein the light-filtering coating is located on a surface of the optical lens producing the smallest incident angle relative to surface normal for a worst ray.

6. The system according to claim 1, wherein the light-filtering coating is located on a surface of the optical lens.

7. The system according to claim 1, wherein the system is operable on an image-based barcode scanner.

8. The system according to claim 4, wherein the light-filtering coating allows the fluorescent light emitted from the target within the predetermined range to pass through to the imager while blocking light having a wavelength outside of the predetermined range.

9. The system according to claim 1, wherein an anti-reflective coating is applied to a surface of the optical lens.

10. A method, comprising:

receiving light from a target;

blocking, by a light-filtering coating on an optical lens, ambient light from entering an imager while allowing light having a wavelength within a predetermined range to enter the imager;

creating an image of the target via the imager based on the light received by the imager; and

decoding the image.

11. The method according to claim 10, further comprising:

projecting activating light onto the target, the target including light-activated ink activated by the illumination element.

12. The method according to claim 11, wherein the activating light is projected by an ultra-violet (“

UV”

) light emitting diode (“

LED”

).

13. The method according to claim 10, wherein the light-filtering coating is located on a surface of the optical lens.

14. The method according to claim 11, wherein the target is a barcode symbol printed in fluorescent ink, and the light received from the target is a fluorescent light.

15. The method according to claim 10, wherein the target is a barcode symbol printed in fluorescent ink, and the light received from the target is a fluorescent light.

16. The method according to claim 15, wherein the fluorescent light is within the predetermined range, the light-filtering coating allows the fluorescent light received from the target within the predetermined range to pass through to the imager while blocking light having a wavelength outside of the predetermined range.

17. The method according to claim 10, wherein the method is performed by an image-based barcode scanner.

18. The method according to claim 10, wherein an anti-reflective coating is applied to a surface of the optical lens.

19. An optical lens, comprising:

a body having a plurality of surface; and

a light-filtering coating applied to a surface of the surface producing a smallest incident angle relative to a surface normal for a worst ray.

20. The optical lens according to claim 19, wherein the light filtering coating blocks ambient light from passing out of the body while allowing light having a wavelength within a predetermined range to pass through the body.

21. The optical lens according to claim 19, further comprising:

an anti-reflective coating applied to a further surface of the surfaces.

22. A system, comprising:

imaging means for providing an image of a target based on light from the target;

optical means having a light-filtering coating blocking ambient light, the optical means focusing at least a portion of the light from the target onto the imaging means; and

processing means for decoding the image of the target.