Digitally watermarking holograms

• US 20060039581A1
• Filed: 03/23/2005
• Published: 02/23/2006
• Est. Priority Date: 04/16/1998
• Status: Active Grant

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Rhoads, Geoffrey B., Brunk, Hugh L., Carr, J. Scott, Lofgren, Neil E., Decker, Stephen K.
• Granted Patent: US 8,355,526 B2
• Time in Patent Office: Days
• US Class Current: 382/100
• CPC Class Codes: G03H 1/0011 for security or authentication holograms on information-bearing cards B42D25/328; testing papers with holograms G07D7/0032
• CPC Class Codes: G03H 1/0244 Surface relief holograms replicating hologram without interference recording G03H1/0276
• CPC Class Codes: G03H 1/041 Optical element in the object space affecting the object beam, not otherwise provided for
• CPC Class Codes: G03H 1/08 Synthesising holograms, i.e. holograms synthesized from objects or objects from hologramsusing electric digital computers G06F; G06T
• CPC Class Codes: G03H 2001/0016 Covert holograms or holobjects requiring additional knowledge to be perceived, e.g. holobject reconstructed only under IR illumination microholograms G03H2230/10
• CPC Class Codes: G03H 2001/0022 Deciphering being performed with numerical or optical key, e.g. with the optical scrambler used during recording optical element in object beam G03H1/041
• CPC Class Codes: G03H 2210/40 Synthetic representation, i.e. digital or optical object decomposition
• CPC Class Codes: G03H 2210/441 Numerical processing applied to the object data other than numerical propagation synthesizing propagation G03H1/0808
• CPC Class Codes: G06K 19/16 the marking being a hologram or diffraction grating
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G06T 1/0021 Image watermarking
• CPC Class Codes: G07D 7/0032 using holograms
• CPC Class Codes: G07D 7/0034 using watermarks
• CPC Class Codes: G07F 7/08 by coded identity card or credit card or other personal identification means without personal verification means G07F7/02
• CPC Class Codes: G07F 7/086 by passive credit-cards adapted therefor, e.g. constructive particularities to avoid counterfeiting, e.g. by inclusion of a physical or chemical security-layer for security documents G07D7/00; for the reading of record-carriers in general G06K7/00; for the design of coded credit-cards G06K19/10
• CPC Class Codes: G07F 7/12 Card verification
• CPC Class Codes: H04N 1/00249 with a photographic apparatus, e.g. a photographic printer or a projector photographic apparatus per se G03B, G03D
• CPC Class Codes: H04N 2201/3215 of a time or duration
• CPC Class Codes: H04N 2201/3233 of authentication information, e.g. digital signature, watermark
• CPC Class Codes: H04N 2201/3281 Encryption; Ciphering

Abstract

The present invention relates to digital watermarks integrated into holograms, watermarked hologram structures, and related applications as an authentication technique. One method creates a watermark image, and then embeds the watermark image into a holographic structure. The holographic structure is carried by a smart card. The smart card includes additional information. In one embodiment, the digital watermark includes information bits, and these information bits are used to authenticate the hologram, or the smart card. In another embodiment, the watermark'"'"'s information bits are compared with the additional information carried by the smart card. The result of the comparison is used to authenticate the smart card or the hologram.

Claims

1. A method comprising:

providing a halftone digital watermarked image;

providing a mask of the digital watermarked image;

applying the mask to a hologram surface; and

demetalizing the hologram surface.

2. A method comprising:

receiving optical scan data representing at least a portion of a hologram, wherein the hologram comprises a digital watermark including a plural-bit message, wherein the plural-bit message comprises error-correction coding;

analyzing the optical scan data to decode a digital watermark and obtain the plural-bit message; and

carrying out an action based on at least the plural-bit message.

3. The method of claim 2, wherein the hologram is carried by an identification document including electronic memory, wherein the electronic memory carries a clue as to whether the identification document should include digital watermarking, said method further comprising:

checking the clue prior to carrying out said analyzing.

4. A method comprising:

creating a computer model;

executing a transform domain iterative method to convert the computer model into a holographic structure;

combining a digital watermark with the holographic structure; and

conveying the combined digital watermark and holographic structure to a surface.