Method and apparatus for verifying a hologram and a credit card

• US 20050129282A1
• Filed: 10/19/2004
• Published: 06/16/2005
• Est. Priority Date: 12/11/2003
• Status: Active Grant

• Current Assignee: Fraudhalt Limited
• Original Assignee: Fraudhalt Limited
• Inventors: Smith, Patrick J., Luna, Carlos, McCarthy, Sean D., O'Doherty, Phelim A.
• Granted Patent: US 7,672,475 B2
• Time in Patent Office: Days
• US Class Current: 382/112
• CPC Class Codes: G07D 7/0032 using holograms
• CPC Class Codes: G07D 7/121 Apparatus characterised by sensor details

Abstract

A method for verifying a hologram, comprising the steps of reading at least two images of the hologram, the images being representative of images derived at respective different viewing angles, comparing a characteristic derived from the respective images with a reference characteristic to establish if the hologram is authentic, and outputting a signal indicative of the authenticity or otherwise of the hologram.

Claims

1. A method for verifying a hologram, the method comprising the steps of:

reading at least two images of the hologram, the images being representative of images derived at respective different viewing angles;

comparing a characteristic derived from the respective images with a reference characteristic to establish if the hologram is authentic; and

outputting a signal indicative of the authenticity or otherwise of the hologram.

2. The method of claim 1 wherein the respective images are derived by illuminating the hologram with light directed towards the hologram at respective different angles.

3. The method of claim 1 wherein the hologram is illuminated by monochromatic light.

4. The method of claim 1 wherein the hologram is illuminated by parallel monochromatic light.

5. The method of claim 1 wherein the images are derived from light diffracted from the hologram.

6. The method of claim 2 wherein illuminating is effected by providing at least one light source for illuminating the hologram, the at least one light source being located for directing the light therefrom to the hologram.

7. The method of claim 6 wherein the at least one light source is a plurality of first light sources and light is directed at respective different angles to the hologram.

8. The method of claim 7 wherein the first light sources are located in a common first plane which extends at an angle greater than zero to a plane of a sheet on which the hologram is provided.

9. The method of claim 8 wherein the common first plane containing the respective first light sources extends at an angle in a range of 60°

to 120°

to the plane of the sheet on which the hologram is provided.

10. The method of claim 8 wherein the common first plane containing the first light sources extends at an angle of approximately 90°

to the plane of the sheet on which the hologram is provided.

11. The method of claim 8 wherein the common first plane in which the first light sources are contained is a plane that when the hologram is sequentially illuminated by the first light sources respective two dimensional images of the hologram are obtained.

12. The method of claim 8 wherein the common first plane is selected to be matched to a wavelength of the monochromatic light so that the hologram is responsive to the monochromatic light directed in the common first plane incident on the hologram for diffracting the light to form the two dimensional image.

15. The method of claim 1 further including the step of forming a bitmap of at least two images of the hologram, and further including computing a value of a characteristic of at least some pixels of the bitmap of each image and wherein the computed values of the characteristic are compared with corresponding reference values, and if the computed values compare favourably with the reference values, the hologram is verified as being a valid hologram.

13. The method of 1 wherein at least two images of the hologram are electronically read, and at least two images are formed in an image plane in at least one electronic camera.

14. The method of claim 13 wherein the at least one camera is located in a second plane at an angle to a plane of a sheet on which the hologram is provided, and at angles to a common first plane in which at least one light source is located for illuminating the hologram.

16. A method for verifying a credit card, said method comprising the steps of:

determining a location of a hologram on the credit card for verification thereof, by

illuminating the hologram with diffused light for defining an outline of the hologram, and

illuminating the credit card from the rear for defining at least one edge of the credit card, and

determining at least one dimension between an edge of the credit card and a corresponding edge of the hologram for determining the location of the hologram on the credit card.

17. The method of claim 16 wherein the at least one dimension of the edge of the hologram from the corresponding edge of the credit card is compared with a corresponding reference dimension.

18. An apparatus for verifying a hologram on a document, the apparatus comprising;

a reading means for reading at least two images of the hologram, the images being representative of images derived at respective different viewing angles,

a comparing means for comparing a characteristic derived from the respective images with a reference characteristic to establish if the hologram is authentic, and

an output means responsive to the comparing means for outputting a signal indicative of the authenticity or otherwise of the hologram.

19. The apparatus of claim 18 further including a first illuminating means for illuminating the hologram with light, the first illuminating means being arranged for directing light at respective different angles towards the hologram for simulating images derived from different viewing angles.

20. The apparatus of claim 19 wherein the first illuminating means comprises a plurality of first light sources provided for directing light at the respective different angles towards the hologram, and each of said illuminating means is a monochromatic light located in a common first plane extending at an angle greater than zero to the plane of the sheet on which the hologram is provided.