Inventors:

Larry W. Fullerton

Mark D. Roberts

Robert Scott Evans

Field of the Invention

[0001] The present invention relates generally to a system and method for authentication.

More particularly, the present invention relates to a system and method for authentication of an optical pattern produced using a magnetic structure.

Background of the Invention

[0002] For counterfeiting prevention, systems and methods for authenticating of components are known. Counterfeiting of components may involve repurposing, remarking or recycling used components along a supply chain. As such, a counterfeit component may pass all production testing, but its reliability may be affected because the part may be near the end of its useful life when it is installed. For this reason, counterfeit components pose a very high risk especially when such components are used in sensitive applications, such as national defense, military or intelligence.

[0003] Known marking, authentication and anti-counterfeiting technologies use taggants comprising chemical or physical markers. Some taggants consist of microscopic particles built up in many layers, which are made of different materials. Other taggants can be engineered particles with unique structures, chemical signatures, photo emission characteristics or combinations of these that can be added to plastics or inks. Unique micro-structures can be read using microscopes. Chemicals or nano- structures that have spectral-shift characteristics can be illuminated and read by specially tuned readers. But readers that must be matched to specific taggants limit the variation that can be applied to components and the options for reading them.

[0004] For example, Authentix™ (www.authentix.com) has commercialized several taggant technologies and offers authentication and security solutions for food, pharmaceutical and manufactured goods. Authentix's taggant technology uses magnetic ink that includes magnetic particles that are applied to individual components. InkSure™ (www.inksure.com) has developed a unique chemical signature technology that is recognized by US courts as a viable, forensic method for identifying material sources. Applied DNA Sciences (www.adnas.com) offers marking and authentication solutions based on chemically modified (and inherently randomized) botanical DNA. This technology adds phosphors to marking solutions for low-level authentication and use well-developed DNA sequencing technologies to verify the authenticity of marked components. 3M offers a line of holographic authentication products that can be added to products or packaging.

[0005] One known authentication system and method described in United States Patent No.

8,286,551 uses pieces of magnetic material to produce magnetic fields for orienting pigments in ink. Under this prior art, a printing machine has a transfer system for conveying a substrate onto an impression cylinder. A screen of cylindrical or flat shape with a doctor blade, collaborates with the impression cylinder to print the substrate with an ink containing pigments that can be orientated by a magnetic field. An unloading system carries the substrate away. The impression cylinder has a magnetic element on its impression surface, that is positioned at a point corresponding to impression performed by the screen on the substrate.

[0006] Currently available authentication techniques, however, offer partial solutions and cannot be broadly deployed across complex supply chains. For example, the processes of creating complex chemical signatures such as DNA occur in centralized facilities in batches. This limits the number of changes that can be made to the marking other than varying concentrations of multiple batches during component marking. Use of magnetic pieces is cumbersome and not easily varied. Ideally, a complete authentication would be changeable more frequently and not require the synthesis of complex chemicals, micro-scale printing or fixed micro-scale structures or magnetic pieces. DNA-based authentication requires removing a sample of the DNA-bearing material to detect the presence of the correct code using laboratory sequencing machines. Further, authentication that requires laboratories limits the ability to increase inspection.

[0007] Ideally, a marking technology would contain enough information to provide

authentication and be expensive to copy, but not require laboratory analysis.

Holographic printing techniques are widely available, but can be mimicked and have costs that are well over 0.01 per component. [0008] Thus, there exists a need to inexpensively deliver secure authentication, rapid, automated screening throughout the supply chain and ultimately facilitate the elimination of purchases containing counterfeit components.

Summary of the Invention

[0009] In accordance with one embodiment of the invention, a system and method

authenticates an optical pattern created by exposing a magnetically sensitive material, for example a magnetically sensitive coating, to one or more magnetic field sources, such as permanent magnets, electromagnets or electro permanent magnets. The magnetically sensitive material can comprise flexible or rigid material. Magnetically sensitive coatings such as dichroic paint, a colloidal nanocrystal structure, or superparamagnetic photonic crystals may be used for creating the optical pattern by curing, fixing or setting the magnetically sensitive coating. The optical pattern is illuminated by one or more illumination sources to generate sensed optical characteristic data from one or more sensors such as photo-detectors, photocells, photodiodes, fiber optics, pyrometers, proximity detectors, or infrared sensors. A memory is configured to store reference optical data. The reference optical data is associated with a reference optical pattern created by exposing a reference magnetically sensitive material to one or more reference magnetic field sources, and corresponds to data generated by one or more reference sensors when the reference optical pattern is illuminated by one or more reference illumination sources. In order to authenticate the optical pattern, the reference optical data is compared to the sensed optical characteristic data by a processor that is configured to access the memory.

[0010] According to some of the more detailed features of the invention, the optical

characteristic data can correspond to physical attributes of the optical pattern, such as lattice structures of magnetically sensitive particles suspended in the magnetically sensitive material or a dichroic characteristic of the magnetically sensitive material. The optical characteristic data can also correspond to illumination attributes of the one or more illumination sources, such as intensity, propagation direction, frequency, wavelength, polarization or illumination angle. The optical characteristic data can also correspond to magnetic attributes of the one or more magnetic field sources such as position of the one or more magnetic field sources relative to a reference coordinate as well as size, shape, polarity or field strength of the one or more magnetic field sources. In one embodiment, the magnetic attributes of the one or more magnetic field sources can be varied over time for demodulating information conveyed by the optical pattern. The optical characteristic data can also correspond to orientation of the one or more illumination sources or the sensors.

[0011] According to other more detailed features of the invention, the optical pattern is

created on a surface area that comprises the one or more magnetic field sources. The magnetic field sources can be arranged in a pattern in accordance with a code, such as Barker code, Gold code, Kasami code, Costas code, or pseudorandom code. The surface area can comprise overlapping magnetic field sources or magnetic field sources separated by non-magnetized regions.

Brief Description of the Drawings

[0012] The present invention is described with reference to the accompanying drawings. In the drawings, like reference numbers indicate identical or functionally similar elements. Additionally, the left-most digit(s) of a reference number identifies the drawing in which the reference number first appears.

[0013] FIG. 1 depicts one embodiment of an authentication system for authenticating an optical pattern according to one aspect of the present invention.

[0014] FIG. 2 depicts a system for generating reference optical data used in the authentication system of Figure 1.

[0015] FIG. 3 depicts another embodiment of an authentication system for authenticating an optical pattern according to another aspect of the present invention.

[0016] FIG. 4 depicts still another embodiment of an authentication system for authenticating an optical pattern according to another aspect of the present invention.

[0017]

[0018] FIG. 5 depicts an embodiment of one exemplary process for creating an optical pattern on a magnetically sensitive material.

[0019] FIG. 6 depicts another embodiment of an exemplary process for creating an optical pattern on a magnetically sensitive material.

[0020] FIG. 7 depicts a flow chart of a method for authenticating an optical pattern according to one aspect of the invention. Detailed Description of the Invention

[0021] The present invention will now be described more fully in detail with reference to the accompanying drawings, in which the preferred embodiments of the invention are shown. This invention should not, however, be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those skilled in the art.

[0022] Certain described embodiments may relate, by way of example but not limitation, to systems and/or apparatuses comprising magnetic structures, methods for using magnetic structures, magnetic structures produced via magnetic printing, magnetic structures comprising arrays of discrete magnetic elements, combinations thereof, and so forth. Material presented herein may relate to and/or be implemented in conjunction with systems and methods described in U.S. Patent Nos. 7,681,256 issued March 23, 2010, 7,750,781 issued July 6, 2010, 7,755,462 issued July 13, 2010, 7,800,471 issued on September 21, 2010, 7,812,698 issued October 12, 2010, 8, 115,581 issued on February 14, 2012, 7,817,002, 7,817,003, 7,817,004, 7,817,005, and 7,817,006 issued October 19, 2010, 7,821,367 issued October 26, 2010, 7,823,300 and 7,824,083 issued November 2, 2011, 7,834,729 issued November 16, 201 1, 7,839,247 issued November 23, 2010, 7,843,295, 7,843,296, and 7,843,297 issued November 30, 2010, No. 7,868,721 issued on January 1 1, 201 1, 7,893,803 issued February 22, 201 1, 7,956,71 1 and 7,956,712 issued June 7, 201 1, 7,958,575, 7,961,068 and 7,961 ,069 issued June 14, 2011, 7,963,818 issued June 21, 201 1, 7,982,568 issued July 19, 201 1, 8,015,752 and 8,016,330 issued September 13, 2011, 8,035,260 issued October 1 1, 201 1, and 8,222,986 issued on July 17, 2012, which are all incorporated by reference herein in their entirety.

[0023] The present invention uses an optical pattern created on magnetically sensitive material for marking components that is impractical, if not virtually impossible, for a counterfeiter to copy. The coating inexpensively withstands normal component handling and usage without significant deterioration while offering a verification process that is not cost or time prohibitive. One such coating system and method is disclosed in US Application No. 13/240,335, filed September 22, 201 1 , titled Magnetic Structure Production, which is hereby incorporated by reference in its entirety. As disclosed, a magnetizable material that is non-magnetized is brought into proximity with a magnetic-field-sensitive solution or other substance (e.g., an iron oxide solution of superparamagnetic photonic crystals). Proximity may be achieved by, for example, suspending particles in a liquid or applying a solution to a surface of the panel using, for instance, a paint having photonic crystals. Objects having magnetic paint may be magnetized with a pattern that may then be optically recognized by a camera or other optical recognition device. Light sources may be controlled to cause different magnetic field attributes to appear or be enhanced.

[0024] Figure 1 shows an embodiment of an authentication system 100 for authenticating an optical pattern 102 according to one aspect of the present invention. The optical pattern 102 is created by exposing a magnetically sensitive coating 104 to one or more magnetic field sources 105. The magnetically sensitive coating 104 may include, for example, a dichroic paint, Colloidal Nanocrystal Clusters such as COLR™ Technology, superparamagnetic photonic crystals, or the like. Exposing the magnetically sensitive coating 104 to the one or more magnetic field sources 105, for example, comprising permanent magnets, electromagnets or electro permanent magnets, can affect physical attributes of the optical pattern 102. In one embodiment, the physical attributes of optical pattern 102 can be associated with one or more lattice structures of magnetically sensitive particles suspended in magnetically sensitive coating 104. For example, when a magnetic field is applied to COLR™ Technology, individual particles self-assemble to form a microscopic, lattice-like structure which diffracts specific wavelengths of light. Adjusting the strength of the magnetic field tunes the color to display brilliant, iridescent colors across the entire visible spectrum and beyond. The particles used in COLR™ Technology are iron oxide superparamagnetic Colloidal Nanocrystal Clusters (CNC) created using a wet synthesis process.

[0025] In another embodiment, the physical attributes of the optical pattern 102 are associated with dichroic characteristics of magnetically sensitive coating 104. Such dichroic characteristics act as a very accurate color filter used to selectively pass light of a small range of colors while reflecting other colors. When light strikes the coating at an angle, some of the light is reflected from the top surface of the coating, and some is reflected from the bottom surface where it is in contact with a surface. Because the light reflecting from the bottom travels a slightly longer path, some light wavelengths are reinforced by this delay, while others tend to be canceled, producing visible colors [0026] The system 100 operates under the control of one more processors 112 having access to one or more memory devices 110 that store programs for operating the system as well as data used for authenticating the optical pattern. The system 100 further comprises one or more illumination sources 106, which are configured to illuminate the optical pattern 102. Illumination sources 106 can be located at any location relative to a reference coordinate system, and can be configured to have a particular orientation relative to such reference coordinate system. The illumination sources can be associated with illumination characteristics such as intensity, propagation direction, frequency or wavelength spectrum, illumination angle, and polarization, where one or more illumination characteristics of a given illumination source 106 may or may not be varied. Under one embodiment shown in Figure 1, the illumination characteristics may be varied under the control of the processor 112.

[0027] One or more sensors 108 sense optical characteristics resulting from reflection of light rays on the optical pattern 102 to generate sensed optical characteristic data. Such data is provided to the processor 112 when the optical pattern is illuminated by illumination sources 106. The sensors 108 may comprise photodetectors (e.g., photocells, photodiodes, transistors, etc.), fiber optic, pyrometer, proximity detector, infrared sensor, or any other optical sensor technology. The sensors 108 can be located at any location relative to the reference coordinate system, and can be and configured to have a particular orientation relative to the reference coordinate system. The sensors 108 may collect information at specific measurement times that may be at regular time intervals, random times, or at times determined using any other data sampling scheme.

[0028] The sensed optical characteristic data can correspond to, for example, physical attributes of the optical pattern 102 created on the magnetically sensitive coating 104, illumination attributes of one or more illumination sources 106, magnetic attributes of the one or more magnetic field sources 105, an orientation of at least one of the one or more illumination sources 106 or an orientation of at least one of the one or more sensors 108 relative to the reference coordinates.

[0029] According to one embodiment, the memory 110 is configured to store a reference optical data associated with a reference optical pattern 202. As shown in Figure 2, the reference optical pattern 202 is created by exposing a reference magnetically sensitive coating 204 to one or more reference magnetic field sources 205. The reference magnetically sensitive coating 204 has coating properties that are used as a reference for authentication purposes. Similarly, the one or more reference magnetic field sources 205 has reference magnetic field properties that impact or otherwise influence the physical attributes of the reference optical pattern. The reference optical data corresponds to data generated by one or more reference sensors 208. The reference sensors have reference sensing properties for sensing optical attributes associated with the physical attributes of the reference optical pattern 202 when the reference optical pattern is illuminated by one or more reference illumination sources 206. The one or more reference illumination sources 206 and sensors 208 have sensing and illumination properties used as reference for generating the reference optical data.

[0030] Referring back to Figure 1, the processor 112 compares the reference optical data stored in the memory 110 to the sensed optical characteristic data after the illumination in order to authenticate the optical pattern 102. The optical pattern 102 may be a one-dimensional pattern, a two-dimensional pattern, or three- dimensional pattern. In one embodiment, the magnetic field sources comprise at least one electromagnet or electro permanent magnet for which at least one characteristic may vary over time. Varying over time may correspond to a repetition rate, a period or periods of time when one or more magnetic field sources are present, a period or periods of time when a magnetic source is not present (i.e., power to an electromagnet is off), where such varying in time of the at least one characteristic can be measured and optionally demodulated to convey information.

[0031] In some embodiments, the optical pattern 102 can convey such information as an identification code, a bar code, a Quick Response (QR) code, a logo, a number, a letter, or any other identifying symbol or symbols. The information can be used for identification and for other purposes comprising a serial number, a date of manufacturing, a location of manufacturing, etc. Such information could even identify, for example, devices used to create the optical pattern 102, an operator of the devices, the date and time of creation, or any other desired information.

[0032] The optical pattern 102 can include, for example, one or more registration marks common to all patterns that are used to determine a geometry of the optical pattern 102, for example the alignment and orientation of the optical pattern relative to a reference coordinate system. The registration marks can be used to determine, for example the relative location of illumination sources 106 or sensors 108.

[0033] As shown in Figure 3, the one or more magnetic field sources 105 can be magnetically printed onto a surface 302 of a magnetizable material onto which a magnetically sensitive coating 104 can be applied. Figure 4 shows a set of print heads 402 imprinting a magnetic pattern 404 formed by maxels on a magnetic structure 406, which could comprise surface 302 on solid or flexible magnetizable material. A magnetically sensitive coating 104 is then applied to the magnetic structure 406 to form an optical pattern 102 that corresponds to the printed maxel pattern 404 beneath the coating 104 on the flexible or solid magnetizable material. The optical sensing approach shown in Figure 3 could be combined with magnetic sensing using magnetic sensors, for example using a Hall Effect sensor array.

[0034] Figure 5 shows an embodiment where a magnetic structure 502 comprising a plurality of magnetic field sources 105 having magnetic attributes such as locations, sizes, polarities, field intensities, etc. are used to expose a complex magnetic field to a magnetically sensitive coating 104 on an component 504 during the curing of the magnetically sensitive material. The magnetic field sources 105 can be discreet magnets, electromagnets, electropermanent magnets, or maxels printed into one or more pieces of magnetizable material. Under this embodiment, the magnetic structure 502, which may be made of rigid/solid or flexible material, serves as a magnetic field template for imprinting on the magnetically sensitive coating 104 an optical pattern corresponding to the complex magnetic field. For example, the magnetically sensitive coating 104 can be applied on to a number of marked components 504 based on the magnetic template by bringing the complex magnetic field of the magnetic structure 502 into proximity with the component while the magnetically sensitive coating 104 is cured.

[0035] Figure 6 shows using multiple print heads 402, electromagnets, or electropermanent magnets to produce a complex magnetic field that exposes a magnetically sensitive coating 104 during its curing process. The one or more magnetic field sources 105 can be brought into proximity to the magnetically sensitive coating 104 while the magnetically sensitive coating 104 is cured, fixed, or otherwise set. In this way, the physical attributes of the optical pattern 102 can be set in place while the magnetically sensitive field coating 104 is exposed to the one or more magnetic field sources 105, but can remain in place after the one or more magnetic field sources 105 is removed.

[0036] The one or more magnetic field sources 105 can have one or more magnetic attributes. Magnetic attributes may include position or print location, size (e.g., diameter, length, width), shape (e.g., round, square, hexagonal, etc.), polarity, field strength, print order, magnetization time, magnetization angle, or density and may involve overlapping of magnetic field sources 105 and/or magnetic field sources 105 separated by non-magnetized regions. The magnetic attributes of the one or more magnetic field sources can be varied in accordance with a code. A code may belong to a code family, for example Barker code family, Gold code family, Kasami code family, Costas code family or any other code family such as those disclosed in US Patent 8, 179,219, issued May 15, 2012, which is incorporated herein by reference in its entirety. Alternatively, a code may be a pseudorandom code.

[0037] The sensed optical characteristic data can correspond to, for example, physical attributes of optical pattern 102 created on the magnetically sensitive coating 104, illumination attributes of one or more illumination sources 106, magnetic attributes of the one or more magnetic field sources 105, an orientation of at least one of the one or more illumination sources 106 or an orientation of at least one of the one or more sensors 108 relative to the reference coordinate.

[0038] As stated above, authentication of the optical pattern 102 can be determined or not based on a comparison of the optical characteristic data with the reference optical data. As an example, if sensed optical characteristic data for an optical pattern 102 matches reference optical data then the optical pattern 102 can be determined by processor 112 to be authentic. However, as another example, if optical characteristic data for another optical pattern also matches reference optical data, then the optical pattern 102 is treated as being counterfeited and the two optical patterns are treated as likely not being authentic.

[0039] Figure 7 shows an embodiment of a process for authenticating an optical pattern 102 according to one aspect of the invention. At step 702, the optical pattern 102 can be illuminated using one or more illumination sources 106. At step 704, sensors 108 can generate optical characteristic data associated with optical characteristics sensed when the optical pattern 102 is illuminated by one or more illumination sources 106. At step 706, the sensed optical characteristic data can be compared to reference optical data in order to authenticate optical pattern 102. The reference optical data can be associated with a reference optical pattern created by exposing a reference magnetically sensitive coating to one or more reference magnetic field sources. The reference optical data can correspond to data generated by one or more reference sensors when the reference optical pattern is illuminated by one or more reference illumination sources. [0040] From the foregoing it would be appreciated that the present invention can be used to create complex signatures based on optical, magnetic and orientation attributes that can for example be used to prevent purchases from unknown suppliers while creating an ability to identify the original source of components. The present invention can further be used to block the harvesting of components from assembled systems.

[0041] While particular embodiments of the invention have been described, it will be understood, however, that the invention is not limited thereto, since modifications may be made by those skilled in the art, particularly in light of the foregoing teachings.