Proceedings Volume 6075

Optical Security and Counterfeit Deterrence Techniques VI

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Proceedings Volume 6075

Optical Security and Counterfeit Deterrence Techniques VI

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Volume Details

Date Published: 8 February 2006
Contents: 9 Sessions, 37 Papers, 0 Presentations
Conference: Electronic Imaging 2006 2006
Volume Number: 6075

Table of Contents

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Table of Contents

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  • Currency I
  • Currency II
  • Security Image Technology I
  • Security Image Technology II
  • Security Ink Technology
  • Optically Variable Devices I
  • Optically Variable Devices II
  • Authentication, Identification, and Biometrics I
  • Authentication, Identification, and Biometrics II
Currency I
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Public feedback for better banknote design
The euro banknotes recently celebrated their 4th year anniversary (2002 − 2006)! DNB has monitored the Dutch public's acceptance of the euro banknotes through surveys in 2002, 2003 and 2005, contrasting its findings with those for the former guilder notes as well as the results of other recent consumer surveys conducted by the US Treasury (2002), Bank of Canada (2003) and several others. A unique time line is presented of the public's knowledge of security features in the Netherlands over the years 1983 − 2005.
Robust and reliable banknote authentification and print flaw detection with opto-acoustical sensor fusion methods
The authenticity checking and inspection of bank notes is a high labour intensive process where traditionally every note on every sheet is inspected manually. However with the advent of more and more sophisticated security features, both visible and invisible, and the requirement of cost reduction in the printing process, it is clear that automation is required. As more and more print techniques and new security features will be established, total quality security, authenticity and bank note printing must be assured. Therefore, this factor necessitates amplification of a sensorial concept in general. We propose a concept for both authenticity checking and inspection methods for pattern recognition and classification for securities and banknotes, which is based on the concept of sensor fusion and fuzzy interpretation of data measures. In the approach different methods of authenticity analysis and print flaw detection are combined, which can be used for vending or sorting machines, as well as for printing machines. Usually only the existence or appearance of colours and their textures are checked by cameras. Our method combines the visible camera images with IR-spectral sensitive sensors, acoustical and other measurements like temperature and pressure of printing machines.
The implication of direct laser engraved intaglio plates on banknote security
Harald Deinhammer, Daniel Schwarzbach, Rudolf Kefeder, et al.
Intaglio printing remains the key security element in banknote printing until today, providing the characteristic feel and tactility recognized by the public. Traditionally, platemaking for this very specific process was done by an electroforming process that involved multiple production steps and manual retouching. We have developed a machine to manufacture these printing plates by direct laser engraving into a metallic substrate. The first machine has recently been put into live banknote production at our premises. We describe the changeover to this novel technology and give a comparison of our findings on print-quality, plate stability and the workflow with conventional platemaking. Results include - Mechanical analysis of the new plate material before and after printing, - Measurements of plate elongation during the printing - Investigations on print-quality We conclude with actual data on engraving time and platemaking lead-times and an overview of the design possibilities using this new approach.
Public education by central banks on the Internet
The Internet is the most powerful information providing medium today and it has great potential in conveying pictorial information in the form of still images, video clips and applets. Obviously, central banks can make use of the Internet to efficiently provide information for the public on the anti-counterfeiting features of their currency. An investigation was carried out of the information provided by 133 Central Banks on the public security features of their currency. Many central banks appear to provide no information at all, many only provide written information and many indeed provide illustrations. An overview is presented of the various errors that central banks make when presenting illustrated information and illustrated examples are given. It appears that even illustrated information often lacks the most elementary requirements: obviousness, clarity and adequate visual representation of the relevant optical effects. As a result, the information made available on the internet by many banknote issuing authorities remains largely ineffective and − on occasion − even assumes silly proportions.
Currency II
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Circulation simulator method for evaluating bank note and optical feature durability
William J. Bartz, Timothy T. Crane
Effective long-term authentication of optical security features on bank notes requires a sound substrate that can withstand the rigors of circulation. Crane & Co. has developed a test method that simulates the deterioration observed in actual circulated bank notes: soiling, creasing, tearing, edge tatteredness and limpness. The method relies on the physical degradation of note specimens that are weighted on each corner and tumbled in a medium of glass beads, metal discs and synthetic soil. Durability is judged by how well a note retains its initial optical and physical properties after being subjected to the conditions of the Circulation Simulator. Much of our early research was directed at improving the paper substrate, and evaluating surface treatments that resist soiling since excessive soiling is often the primary reason bank notes are removed from circulation. Recent work has examined the correlation between Circulation Simulator results and the properties of actual bank notes culled from circulation. We also are using the Circulation Simulator method to qualitatively evaluate the potential durability and effectiveness of optical security features such as electrotypes, watermarks, windowed threads, foils and inks. This paper provides a description of the testing and analysis methods.
Visual and optical evaluation of bank notes in circulation
Sara Church, Martine Lacelle, Theodoros Garanzotis
A method for comparing quality of bank notes in circulation based on both a subjective visual sorting technique and on quantitative wear evaluations is described and applied to circulated Canadian bank notes. The sample notes, which were part of a $5 circulation trial, issued over a 4 to 6 week period, had been in circulation for roughly 6 months. Notes were first sorted visually into four defined substrate categories (No Edge Wear, Corner Folds, Minimal Edge Wear and Edge Wear) and four surface wear categories (None, Low, Medium and High). Samples of each category were tested at Crane and Co. using a range of physical and optical techniques: air resistance, air permeability, stiffness deflection, double folds, gray scale, brightness, perimeter length, and top/bottom mean and maximum deviations. The visual sort showed that neither soiling nor ink loss are the major wear problems for bank notes in Canada. However, the substrate does become tattered and worn. The mechanical and optical wear tests show that most of the parameters change logically as the soil level increases. The changes for other parameters are less clear as a function of wear categories, but are relatively consistent in distinguishing between the No Edge Wear and Edge Wear. Impact of wear on the effectiveness of security features will also be described.
The mechanisms of human recognition as a guideline for security feature development
Security features for automated processing and / or forensic identification of bank notes have proven to reliably recognize and select counterfeit bank notes in circulation. As a result of this development the decisive first line of defense is the public, where either the criminal fraternities or opportunity counterfeiters try to place their antisocial products. Therefore those security features, which fit into the range of subconscious recognition and habitual knowledge, are those of major importance in application and development. This paper tries to answer some questions how the human recognition, its well-developed functionality and how these through evolution-acquired capabilities may considerably influence the improvement of public security features in bank notes.
Security Image Technology I
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Qualification of security printing features
Steven J. Simske, Jason S. Aronoff, Jordi Arnabat
This paper describes the statistical and hardware processes involved in qualifying two related printing features for their deployment in product (e.g. document and package) security. The first is a multi-colored tiling feature that can also be combined with microtext to provide additional forms of security protection. The color information is authenticated automatically with a variety of handheld, desktop and production scanners. The microtext is authenticated either following magnification or manually by a field inspector. The second security feature can also be tile-based. It involves the use of two inks that provide the same visual color, but differ in their transparency to infrared (IR) wavelengths. One of the inks is effectively transparent to IR wavelengths, allowing emitted IR light to pass through. The other ink is effectively opaque to IR wavelengths. These inks allow the printing of a seemingly uniform, or spot, color over a (truly) uniform IR emitting ink layer. The combination converts a uniform covert ink and a spot color to a variable data region capable of encoding identification sequences with high density. Also, it allows the extension of variable data printing for security to ostensibly static printed regions, affording greater security protection while meeting branding and marketing specifications.
Potentiality of holographic technique in fragile watermarking
Fragile watermark is designed to detect slight changes to the watermarked image with high probability. In the security community, an integrity service is unambiguously defined as one, which insures that the sent and received data are identical. This binary definition can also be applicable to images; however it is too strict and not well adapted to this type of digital document. Indeed, in real life situations, images will be transformed. Their pixel values will therefore be modified but not the actual semantic meaning of the image. In order to provide an authentication service for still images, it is important to distinguish between malicious manipulations, which consist of changing the content of the original image such as captions or faces, and manipulations related to the use of an image, such as format conversion, compression, filtering, and so on. Unfortunately this distinction is not always clear; it partly depends on the type of image and its use. Scope of this paper is to present potentiality of Holographic technique in fragile watermarking for digital image authentication of medical or military images.
Secure graphical data storage by full spectrum image coding
Full Spectrum coding is a method of providing a picture with a machine readable code image. The transparency and robustness of the code can be influenced by the embedding parameters, according to the intended application (e.g. robust or fragile marking). The code image contains hidden information, identifying the document in some way. In principle, it can be any binary pattern or grey-scale picture. Alternatively, it may be desirable to encode (binary) data, e.g. ID numbers or (biometric) templates. Such data should be transformed into a code image suitable for the proposed kind of embedding. In the presented implementation, the code image contains a binary block structure, similar to a 2-dimensional (bar) code. Even in the presence of noise, this code can be extracted from the magnitude spectrum of the captured image by iterated down-sampling. Full Spectrum is well-suited for application to printed documents. It survives graphical processes (halftone screening, printing, digitizing) and the reconstructed code image is invariant to shifting and robust to cropping. A technique is presented to perform registration for rotation and scaling of the captured image with respect to the original. The approach is to embed a marking signal based on perfect correlation sequences in the radial-polar representation of the code image. In this domain, the rotation angle and (under certain conditions) the scale factor, can be determined by linear cross-correlation. Additionally, techniques are proposed to obtain resistance to more general distortions.
Sub-pixel analysis to support graphic security after scanning at low resolution
Whether in the domain of audio, video or finance, our world tends to become increasingly digital. However, for diverse reasons, the transition from analog to digital is often much extended in time, and proceeds by long steps (and sometimes never completes). One such step is the conversion of information on analog media to digital information. We focus in this paper on the conversion (scanning) of printed documents to digital images. Analog media have the advantage over digital channels that they can harbor much imperceptible information that can be used for fraud detection and forensic purposes. But this secondary information usually fails to be retrieved during the conversion step. This is particularly relevant since the Check-21 act (Check Clearing for the 21st Century act) became effective in 2004 and allows images of checks to be handled by banks as usual paper checks. We use here this situation of check scanning as our primary benchmark for graphic security features after scanning. We will first present a quick review of the most common graphic security features currently found on checks, with their specific purpose, qualities and disadvantages, and we demonstrate their poor survivability after scanning in the average scanning conditions expected from the Check-21 Act. We will then present a novel method of measurement of distances between and rotations of line elements in a scanned image: Based on an appropriate print model, we refine direct measurements to an accuracy beyond the size of a scanning pixel, so we can then determine expected distances, periodicity, sharpness and print quality of known characters, symbols and other graphic elements in a document image. Finally we will apply our method to fraud detection of documents after gray-scale scanning at 300dpi resolution. We show in particular that alterations on legitimate checks or copies of checks can be successfully detected by measuring with sub-pixel accuracy the irregularities inherently introduced by the illegitimate process.
New applications of modulated digital images in document security
Robert A. Lee, Patrick W. Leech, Lawry D McCarthy, et al.
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.
Security Image Technology II
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Black fluorescent ink and applications
Black fluorescent inks developed for postal applications exhibit contrast suitable for machine reading and fluorescence suitable for postal processing. The combination of black color and red fluorescence in one ink requires inhibition of fluorescence quenching. One way to inhibit quenching is by combining subtractive dyes and leaving an absorbance window for the emission of the red fluorescence. The absorbance and emission spectra of the ink confirm the model. Another approach is combining larger size colorants: fluorescent and non fluorescent in order to lower the collision probability and quenching by energy transfer. The covert nature of the fluorescence lends itself to security applications.
The Role of Optics in Secure Credentials
The global need for secure ID credentials has grown rapidly over the last few years. This is evident both in government and commercial sectors. Governmental programs include national ID card programs, permanent resident cards for noncitizens, biometric visas or border crossing cards, foreign worker ID programs and secure vehicle registration programs. The commercial need for secure credentials includes secure banking and financial services, security and access control systems and digital healthcare record cards. All of these programs necessitate the use of multiple tamper and counterfeit resistant features for credential authentication and cardholder verification. It is generally accepted that a secure credential should include a combination of overt, covert and forensic security features. The LaserCard optical memory card is a proven example of a secure credential that uses a variety of optical features to enhance its counterfeit resistance and reliability. This paper will review those features and how they interact to create a better credential.
Practical use of lens structures in ID documents
Polymer ID-documents mostly are made of plastic foils which are laminated to one massive card by applying heat and pressure. During this lamination process, some structures can be transferred from the metal laminating plate to the card surface. These structures can be shaped in the form of a lens. Both are possible, positive as well as negative lens structures, for example in the form of lines or (micro) text. Also lens arrays of cylinder lenses can be made. The lens structures can be combined with the security design which is printed on the document, resulting in optically variable effects of moire patterns. Also these lens structures can be combined with laser engraving during the personalization of the document. In this way it is even possible to personalize the document with a stereo photo, the so called stereogram. The tactility of the structures on the ID-document, combined with the optical effects, makes these structures a very strong first line security feature. This kind of security features are completely integrated into the card body and combined with the personalization, which make them hard to manipulate by counterfeiters. Because of the fact that the human eye can handle images with a lot of noise, the optical quality of the lenses as well as the focal point seems to be less important for the most applications. Some applications need a rather high optical quality.
Three-dimensional floating images as overt security features
Douglas S. Dunn, Travis L. Potts, Lynn E. Lorimor, et al.
3M has developed a proprietary laser process for creating three-dimensional images that appear to float above and/or below the plane of a substrate containing an array of microlenses. During the imaging process the laser records a microscopic image of the desired three-dimensional pattern in the material located at the focal point of each microlens in the array. The images exhibit motion parallax comparable to that seen from holograms and are easily visible in a wide range of ambient lighting conditions. The images are therefore similar, but not identical, to integral images, first proposed in 1908 by Lippmann. The fidelity of these floating images requires maintaining exact registration between the microlens array and the corresponding microimage array. In addition, the use of an ablative laser process for the production of the microimages enables the production of microimage features smaller than the diffraction limit (up to approximately 50,000 dpi). The images are therefore very difficult to simulate, counterfeit, or modify and are highly desirable as an overt security feature. 3M has scaled up the floating image process to produce images in ConfirmTM Retroreflective Security Laminate to authenticate passports and driver's licenses and in retroreflective license plate sheeting as the EnsureTM Virtual Security Thread to authenticate vehicle registration. This allows addition of features to a secure document that are easily verifiable, using only the human eye, by a large and widely disperse population to create an identity document that is easily identified as genuine.
Development of the random-retardation-encoding anti-counterfeiting technology
Wan-Jian Huang, Chao-Hsu Tsai, Ting-Ju Chen, et al.
The properties of periodicity and linear separation/combination of optical retardation are adopted to develop the Random-Retardation-Encoding anti-counterfeiting technology. In the experiments of this paper, the authentication pattern was divided into two parts with different random retardation distribution. The two parts of random retardation pattern were fabricated on two separate films. One of them can be used as the authentication tag, and the other is used for the identification of the authentication tag. Because the resolution of the random retardation pattern can be made very high, it's very hard to counterfeit the authentication tag without knowing the original design pattern. In addition, the transparency property of the retardation film makes it easy to be integrated with other anti-counterfeiting method, e.g. it can be laminated on a hologram without destroying the visual performance of the hologram while the authentication function of the retardation film is still maintained.
Security Ink Technology
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Advanced verification methods for OVI security ink
Paul G. Coombs, Shaun F. McCaffery, Tom Markantes
OVI security ink+, incorporating OVP security pigment* microflakes, enjoys a history of effective document protection. This security feature provides not only first-line recognition by the person on the street, but also facilitates machine-readability. This paper explores the evolution of OVI reader technology from proof-of-concept to miniaturization. Three different instruments have been built to advance the technology of OVI machine verification. A bench-top unit has been constructed which allows users to automatically verify a multitude of different banknotes and OVI images. In addition, high speed modules were fabricated and tested in a state of the art banknote sorting machine. Both units demonstrate the ability of modern optical components to illuminate and collect light reflected from the interference platelets within OVI ink. Electronic hardware and software convert and process the optical information in milliseconds to accurately determine the authenticity of the security feature. Most recently, OVI ink verification hardware has been miniaturized and simplified providing yet another platform for counterfeit protection. These latest devices provide a tool for store clerks and bank tellers to unambiguously determine the validity of banknotes in the time period it takes the cash drawer to be opened.
Overt security features through digital printing
Mark Hampden-Smith, Scott Haubrich, Ralph Kornbrekke, et al.
Digital printing technology represents a counterfeiting threat and a counterfeiting deterrence opportunity. Digital reproduction methods have been used to produce holographic and printed features similar to those on banknotes. As digital technology continues to improve, the quality of those features will become nearly indistinguishable from intaglio printing, offset printing and holograms. Optically active devices and inks have been useful to slow counterfeiters, but security document and feature designers need more tools. The toolbox for digital technologies is very large and being exploited by the counterfeiters, but their toolbox has been limited to commercially available digital technologies. Security designers also need to take advantage of this toolbox with the additional lever of secure materials. By leveraging digital technologies with secure materials, variable information and integration with other security features, security document designers can create new, attractive features that are hard to replicate. The high level of difficulty to create security materials in the sub-micron to nanometer size range with multiple functionalities is one barrier. Creating inks that are formulated to fit the stringent requirements for custom digital printing methods creates another barrier to unauthorized reproduction. All of the other valuable aspects of digital technology are therefore accessible only to those with access to these secure materials. Leveraging these digital materials to make optical effects make them useful for the end-user authentication. Furthermore, use of digital technologies allows the incorporation of variable data that can be authenticated visually or using proprietary algorithms and detection / sorting equipment.
Novel particulate production processes to create unique security materials
Mark Hampden-Smith, Toivo Kodas, Scott Haubrich, et al.
Particles are frequently used to impart security features to high value items. These particles are typically produced by traditional methods, and therefore the security must be derived from the chemical composition of the particles rather than the particle production process. Here, we present new and difficult-to-reproduce particle production processes based on spray pyrolysis that can produce unique particles and features that are dependent on the use of these new-to-the-world processes and process trade secrets. Specifically two examples of functional materials are described, luminescent materials and electrocatalytic materials.
Combining overt and covert anti-counterfeiting technologies for securities
The National Printing Bureau of Japan has been developing new anti-counterfeiting technologies as a banknote printer. Some of our technologies have already been effectively introduced into Japan's new banknote series. Anti-counterfeiting technologies can be applied not only to banknotes but also to other security documents depending on desired features. In this presentation, I will introduce three of our newly developed overt and covert security techniques, which are intended for document security and brand protection, as well as banknotes. "Metallic View" is mainly for offset printing. "Copy Check" (micro-structural lines involving luminescence) is for plate making technology. "ImageSwitch" is for a new security solution which has unlimited printing applications. All three techniques create "latent images" (some of which may be better known as "carrier screen images") that are useful in preventing counterfeiting. While each of the techniques is effective by itself, all are more effective when applied together. Combining these techniques could make all security documents harder to copy using IT scanners, and provide cost-effective anti-counterfeiting solutions for all security users.
Bacteriorhodopsin-based multilevel optical security features
N. Hampp, M. Neebe
Bacteriorhodopsin (BR) is a crystalline photochromic protein which shows an astonishing stability towards chemical and thermal degradation. This material is used in a variety of applications which have been developed, among them photochromic color-changes, optical data storage and molecular traceability of the material. Integration of all three security levels in a document will be shown. One year lasting field tests have proven the stability of the system in daily use. First applications of polarization encoded data storage and data encryption have been realized successfully. The development of BR-based security features will be reviewed and newer developments will be presented, among them individualized computer generated holograms and the development of ink-jet inks. The data-storage capabilities of the biomaterial BR have been further developed and now visual detectable as well as visual non-detectable storage processes are available. The molecular mechanisms of the data storage process will be presented.
Optical security in ink: an industry standard that continues to evolve
Mathieu Schmid
The level of security against counterfeiting and forgery that is provided by optically variable ink has led to this technology becoming the industry reference for the protection of high security documents. For this ink to be secure, it must obviously differentiate itself from inks used for purely decorative purposes. Hence, the inks used for protecting high security documents have intense, saturated colors that lie within a specified and restricted color range, a very wide color travel and can be identified with the naked eye or specific optical filters. These characteristics are achieved with sophisticated technologies that result in pronounced optical interference effects. For instance, vacuum deposition techniques are used to produce interference pigment flakes that create the distinctive colors and wide color travel. Another technology, based on liquid crystal pigments, displays rare and specific characteristics under a polarizing filter. Because the inks are ultimately applied to a substrate by a security printer, their chemistry and formulation provide the foundation for the security feature. Building on the proven basis of intense, saturated colors and wide color travel, optically variable inks offer the flexibility to combine the creativity of graphic artists with the know-how of security printers and breakthroughs in printing technology to create ever more secure features that can easily and readily be authenticated by the public.
Optically Variable Devices I
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Use and efficacy of DOVIDs and other optical security devices
Diffractive optically variable image devices (DOVIDs) have become the primary overt authentication or security feature on protected documents and products, apart from the substrate itself and the printed design − which are the oldest but still effective authentication features. But their efficacy is being compromised by false expectations and counterfeits. It is therefore necessary to establish a clear statement of the role of DOVIDs and their function in the inspection and protection of suspect items, which will also apply to other optical security devices (OSDs).
The security enhancement of diffractive optically variable image devices
It is well known that Diffractive Optically Variable Image Devices (DOVIDs) can be copied, duplicated or simulated by the counterfeiters. Some customers consider that such devices are no longer secure and will not use them to protect their product. To avoid counterfeiting, DOVIDs are being made more complicated with the introduction of a large number of simultaneous images, where recognition by customers is strongly compromised. Future trends appear to favor multiple technologies in one device while allowing the consumer to readily identify and remember the device. One approach calls for a combination of the diffractive foil interference found in DOVIDs with thin film interference to create new security devices called SecureShift ChromaGrams. A second approach calls for a combination of diffractive and thin film interference in the form of pigments combined with magnetic fields during the printing process to create another new security device called a "PrintaGramTM". Each type of enhanced DOVIDs will be discussed in terms of its optical performance, manufacturability, its counterfeit deterrence, and its application.
The Aztec structure: an improved replicable security device
Holograms that are predominantly in use today as visually identifiable security devices can generally be divided into two categories: either surface relief rainbow holograms or reflection type volume holograms. The Aztec structure is a special surface relief device that combines aspects of both of these types. It has unique identifying characteristics, with provision for great difficulty in counterfeiting, which make it more secure. Its fabrication by holographic means requires techniques of both surface and volume holograms, thus is technically more difficult to make than either separately. The structure is deeper than the standard surface relief hologram, and its profile has the characteristic of several well defined steps, such that, when viewed on edge, resemble a stepped pyramid. Thus, replication of the Aztec structure requires special high resolution techniques to faithfully record the submicron features of the stepped profile, and thus is more difficult to manufacture. The visual characteristics of the Aztec structure are similar to the volume hologram, in that single colors, rather than rainbow colors, can be viewed. Also, a combination of single colors can be encoded into a single master, yielding unique visual effects.
Use of metameric filters for future interference security image structures
In the present work, we describe innovative approaches and properties that can be added to the already popular thin film optically variable devices (OVD) used on banknotes. We show two practical examples of OVDs, namely (i) a pair of metameric filters offering a hidden image effect as a function of the angle of observation as well as a specific spectral property permitting automatic note readability, and (ii) multi-material filters offering a side-dependent color shift. We first describe the design approach of these new devices followed by their sensitivity to deposition errors especially in the case of the metameric filters where slight thickness variations have a significant effect on the obtained colors. The performance of prototype filters prepared by dual ion beam sputtering (DIBS) is shown.
Optically Variable Devices II
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Novel optically variable color devices
Martin Stalder, Frank Seils
The recently introduced ROLICURETM PEARL is a novel optically variable device (OVD) ideally suited for security applications. It may hold high resolution images, (micro-) text or graphical designs. Upon tilt or rotation high contrast positive/negative flips are observed. The optical effect of these devices is based on a proprietary technology of Rolic and includes light scattering at patterned anisotropic microstructures. Since these microstructures are non-periodic no rainbow colors are generated, making these devices easy to authenticate and clearly distinguishable from standard holograms. In this paper, we describe how to modify the optical appearance of our - a priori - colorless ROLICURETM PEARL feature by addition of distinct color-shift thus further increasing its level of protection and meeting design requirements. This is accomplished by optical interference at additional dielectric and metallic layers in combination with the ROLICURETM PEARL scattering microstructure. Various configurations are conceivable and have been realised in our labs. Depending on the nature of its dielectric layers red, green and blue colors are obtained and respective photospectra will be presented. While the optical appearance remains attractively bright, excellent color saturation is achievable. Independently from the color-shift which originates from changes of the optical path length under various viewing angles, the contrast inversion of the image is still present and is visualized when the device is tilted or rotated. In general, images of these security devices are easily recognizable within wide viewing angles without need of a point light source.
Diffractive moire features for optically variable devices
Andreas Schilling, Wayne R. Tompkin, René Staub, et al.
We present diffractive second-line security features based on the moiré phenomenon, that are designed for use in Optically Variable Devices (OVDs). After a short introduction of our 2D and 1D moire methods, we first present the integration of line-based, 1D animated moire patterns into OVDs. These covert features are verified using a printed, high-resolution screen, which causes the covert information to become visible. When the screen is moved back and forth, the covert information, for example a text, appears to move dynamically in a well defined way. We then present diffractive OVDs where specially designed 2D moire features have been integrated into graytone images. Such an integration has the advantage that the area in which the second-line security feature appears can be used simultaneously for a visually attractive first-line effect rather than just having a homogeneous background. The integrated diffractive moire features are verified with a 2D microlens array through which the OVD is viewed; as the verifier or the OVD together with the verifier is moved, one observes dynamic visual effects. A special form of integrating a diffractive moire-feature into an OVD is shown in the last part of the paper, where the 2D microlens verifier is used in a fixed combination together with the information layer that consists of diffractive microstructures. Such a diffractive moire magnifier feature is characterized by the unique visual impression that it creates where projected images appear to move as the sample is tilted.
Authentication, Identification, and Biometrics I
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Choosing the correct forensic marker(s) in currency, document, and product protection
The use of forensic markers (often known as 'tags' or taggants) as authenticity agents in currency, document and product provenance protection is gaining increased acceptance. There is now a wide choice to be made from a variety of technologies available from a number of suppliers. What criteria should be employed to aid the selection of the most appropriate technology? This paper will identify by type the range of technologies available. The use of tags and identification markers in all forms of authenticity test is highly dependent upon criteria such as the method used to deliver the marking component and the equipment needed to identify and extract the marking agent during the authorisation process. For instance, the type of marking system that can be effectively used in currency protection will require different attributes to that of a marker that identifies the authenticity of say a pharmaceutical product or the provenance of a precious stone. Such marking systems offer quality results to potential users, all of whom posses their own distinctive needs. However the correct choice will be driven by a decision making process that involves cost, speed of application, ease of recovery and low risk of compromise as well suitability for purpose. This paper will briefly identify the way forensic markers can be utilised in protecting users from various risks such as counterfeiting, dilution and refilling. This paper will also explore the technical aspects of each process with regard to characteristics and components involved in the system and then analyse the suitability of a range of available technologies to address risks on a sector by sector basis.
Optically variable threads and polarization effects
Friedrich Kretschmar, Theodor Burchard, Manfred Heim
Based on common criteria for efficient security elements for banknotes the set-up of a state-of-the-art holographic security thread is described - as first representative of window embedded OVD. We continue with new colour-shifting OVD-threads − based on physical vapour deposition thin-film and liquid crystal technology. These three then form the family of optically variable threads following the same set of requirements for efficiency, durability, service to all authentication levels and economics. In addition to this set of OVD threads we introduce how liquid crystal based phase retarding layer can be used to install new authentication channels for the public use up-to machine authentication. Also we show the perspective how those development can be used to install similar sets of OVD families of foil elements on banknotes.
Life recognition based on color variations in fingerprint images of live and artificial fingers
Katsuki Tai, Masashi Kurita, Ichiro Fujieda
Life-related signal detected from a finger-tip can be used to prevent frauds by finger-replicas. A finger deformation induces blood movement and the light scattered inside the finger carries this life-related information. We propose to look at the changes in color and luminance extracted from the central part of the fingerprint images. In experiments, we examined input actions taken by more than 30 participants as well as six replicas made of various materials. For the live fingers, chromaticity coordinates x and luminance Y showed a relatively large hysteresis as a function of the area of the fingerprint images. This hysteresis was smaller in case of the replicas. Based on this fact, we were able to define indices and criteria for life recognition so that all the replicas were rejected while the most live fingers were accepted. However, the recognition was not perfect due to the small hysteresis shown by some replicas. Improvements in the input hardware and the algorithms for life-related information extraction need to be addressed in future.
RFID identity theft and countermeasures
Alexander Herrigel, Jian Zhao
This paper reviews the ICAO security architecture for biometric passports. An attack enabling RFID identity theft for a later misuse is presented. Specific countermeasures against this attack are described. Furthermore, it is shown that robust high capacity digital watermarking for the embedding and retrieving of binary digital signature data can be applied as an effective mean against RFID identity theft. This approach requires only minimal modifications of the passport manufacturing process and is an enhancement of already proposed solutions. The approach may also be applied in combination with a RFID as a backup solution (damaged RFID chip) to verify with asymmetric cryptographic techniques the authenticity and the integrity of the passport data.
Recording of the optical identification marks on CD
Andriy A. Kryuchyn, Sergiy Al. Kostyukevych, Viacheslav V. Petrov, et al.
In present report the methods of the identification marks creation on the surface which are intended for the determination of licensability of CD production are considered. The main attention is devoted to the methods of the identification marks recording on master disks during the process of CD fabrication.
Authentication, Identification, and Biometrics II
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On the use of mobile imaging devices for the validation of first- and second-line security features
Tony Rodriguez, Matthew Weaver
The proliferation of mobile imaging devices combined with Moore's law has yielded a class of devices that are capable of imaging and/or validating many First- and Second-Line security features. Availability of these devices at little or no cost due to economic models and commoditization of constituent technologies will result in a broad infrastructure of devices capable of identifying fraud and counterfeiting. The presence of these devices has the potential to influence aspects of design, production, and usage models for value documents as both a validation tool and as a mechanism for attack. To maximize usability as a validation tool, a better understanding is needed about the imaging capabilities of these devices and which security features and design approaches favor them. As a first step in this direction, the authors investigated using a specific imaging-equipped cell phone as an inspection and validation tool for identity documents. The goal of the investigation was to assess the viability of the device to identify photo swapping, image alteration, data alteration, and counterfeiting of identity documents. To do so security printing techniques such as digital watermarking, microprinting and a Diffractive Optically Variable Image Device were used. Based on analysis of a representative imaging-equipped cell phone (Fujitsu 900i), the authors confirmed that within some geographies, deployed devices are capable of imaging value documents at sufficiently high resolution to enable inspection and validation usage models across a limited set of security features.
Facets of color laser marking in high-security ID documents
Frank Kappe, Matthias Schumacher, Klaus Schäfer, et al.
Our new true-color laser personalization system (CYMartTM) for ID cards and documents does not suffer from the disadvantage of producing only black and white images as it is known from state of the art personalization systems, which use Nd-YAG lasers. These well-established black-and-white laser marking systems are valued so highly because the marking is created inside the material. Therefore, it is protected from counterfeiting and tampering. In exactly the same manner CYMartTM features an embedded image. CYMartTM is based on a three-wavelength laser system, one for each primary color (red, green and blue). A deflection system is used to direct the focused beams onto the document. The wavelength-sensitive color forming process generates true-color images comprised of a combination of the 3 primary colors. The color of any image element can be determined by the intensity of each laser beam. Unlike conventional laser marking with CYMartTM we are able to mark square-shaped dots. Until now, due to the Gaussian beam of the laser source, the marking was done with a circular beam shape, which has a non-uniform intensity profile. However, this profile results in inhomogeneous gray level of each marked dot. By introducing an aspherical phase plate into the laser beam we have the ability to manipulate the light and achieve a square-shaped dot with a uniform intensity profile. This enables us to mark an area with seamless transitions and without any color deviation.
Protection of data carriers using secure optical codes
John A. Peters, Andreas Schilling, René Staub, et al.
Smartcard technologies, combined with biometric-enabled access control systems, are required for many high-security government ID card programs. However, recent field trials with some of the most secure biometric systems have indicated that smartcards are still vulnerable to well equipped and highly motivated counterfeiters. In this paper, we present the Kinegram Secure Memory Technology which not only provides a first-level visual verification procedure, but also reinforces the existing chip-based security measures. This security concept involves the use of securely-coded data (stored in an optically variable device) which communicates with the encoded hashed information stored in the chip memory via a smartcard reader device.