New applications of modulated digital images in document security

Robert A. Lee; Patrick W. Leech; Lawry D McCarthy; Gerhard F. Swiegers

doi:10.1117/12.642440

9 February 2006 New applications of modulated digital images in document security

Robert A. Lee, Patrick W. Leech, Lawry D McCarthy, Gerhard F. Swiegers

Proceedings Volume 6075, Optical Security and Counterfeit Deterrence Techniques VI; 60750C (2006) https://doi.org/10.1117/12.642440
Event: Electronic Imaging 2006, 2006, San Jose, California, United States

Abstract

In previous work we have demonstrated that selective masking, or modulation, of digital images can be used to create documents and transparent media containing covert or optically variable, overt images. In the present work we describe new applications and techniques of such "modulated digital images" (MDI's) in document security. In particular, we demonstrate that multiple hidden images can be imperceptibly concealed within visible, host images by incorporating them as a new, half-tone, printing screen. Half-toned hidden images of this type may contain a variety of novel features that hinder unauthorized copying, including concealed multiple images, and microprinted-, color-, and various fadeeffects. Black-and-white or full color images may be readily used in this respect. We also report a new technique for the embossing of multiple, covert- or optically variable, overt-images into transparent substrates. This method employs an embossing tool that is prepared using a combination of electron beam and greytone lithography. Two approaches may be used: (i) a double-sided "soft" emboss into curable, transparent, lacquer layers, and (ii) a single-sided "hot" emboss in which multiple, dithered images consisting of distinctly-sloped microprisms are impressed into the substrate. Technique (ii) requires a novel, electron-beam-originated master dye.

Citation Download Citation

Robert A. Lee, Patrick W. Leech, Lawry D McCarthy, and Gerhard F. Swiegers "New applications of modulated digital images in document security", Proc. SPIE 6075, Optical Security and Counterfeit Deterrence Techniques VI, 60750C (9 February 2006); https://doi.org/10.1117/12.642440

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
13 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Printing

Modulation

Digital watermarking

Micromirrors

Photography

Polymers

Data hiding

Show All Keywords

Keywords/Phrases

Search In:

Publication Years