Patent Application
20080112460
This description relates generally to a method and apparatus for detecting counterfeit printed items. It is particularly related to, but in no way limited to, detecting counterfeit printed items such as banknotes, passports, postage stamps or other items by detecting intaglio print.
There is a growing need for automatic detection of potentially counterfeit banknotes of different currencies and denominations in a simple, reliable, and cost effective manner. This is required, for example, in self-service apparatus which receives banknotes, such as self-service kiosks, ticket vending machines, automated teller machines arranged to take deposits, self-service currency exchange machines and the like.
Previously, manual methods of currency validation have involved image examination, transmission effects such as watermarks and thread registration marks, feel and even smell of banknotes. Other known methods have relied on semi-overt features requiring semi-manual interrogation. For example, using magnetic means, ultraviolet sensors, fluorescence, infrared detectors, capacitance, metal strips, image patterns and similar. However, by their very nature these methods are manual or semi-manual and are not suitable for many applications where manual intervention is unavailable for long periods of time. For example, in self-service apparatus.
The complexity of counterfeit banknotes is improving and some counterfeit banknotes now simulate security features such as UV fluorescence, water marks or magnetic features. Other methods of detecting counterfeit banknotes are thus required that are suitable for machine reading. Any such method needs to be cost effective, fast, reliable and robust.
It is also required to provide automated methods for detecting counterfeit passports, postage stamps or other printed items.
The following presents a simplified summary of the disclosure in order to provide a basic understanding to the reader. This summary is not an extensive overview of the disclosure and it does not identify key/critical elements of the invention or delineate the scope of the invention. Its sole purpose is to present some concepts disclosed herein in a simplified form as a prelude to the more detailed description that is presented later.
We describe detecting intaglio print on banknotes such that potentially counterfeit banknotes are identified by the absence of intaglio print or the presence of incorrect intaglio print. Intaglio print comprises ridges and grooves on a substrate where ink is applied. A thermal sensor is used to detect the presence of intaglio print by, for example, presenting a banknote to the thermal sensor and moving the banknote relative to that sensor. The banknote may be swiped past the sensor or vice versa. A comparison is made between the output of the thermal sensor and pre-specified information about intaglio printed regions associated with the printed item. Counterfeit detection may also be carried out for passports, postage stamps and other intaglio printed items.
Many of the attendant features will be more readily appreciated as the same becomes better understood by reference to the following detailed description considered in connection with the accompanying drawings.
The present description will be better understood from the following detailed description read in light of the accompanying drawings, wherein:
a is a representation of part of a banknote having intaglio printed regions;
b is a thermal sensor output for part of the banknote of
c is a thermal sensor output for another part of the banknote of
Like reference numerals are used to designate like parts in the accompanying drawings.
The detailed description provided below in connection with the appended drawings is intended as a description of the present examples and is not intended to represent the only forms in which the present example may be constructed or utilized. The description sets forth the functions of the example and the sequence of steps for constructing and operating the example. However, the same or equivalent functions and sequences may be accomplished by different examples.
Although the present examples are described and illustrated herein as being implemented in an automated teller machine for counterfeit banknote detection, the methods and systems described are provided as an example and not a limitation. As those skilled in the art will appreciate, the present examples are suitable for application in a variety of different types of counterfeit item detection systems, including for passports, postage stamps and other items having intaglio print.
Intaglio is a printmaking technique that is currently used to print the majority of genuine banknotes in the world. In the US banknotes are intaglio printed on both sides. In other regions such as the UK and the Euro zone banknotes are intaglio printed on one side only at present although this may change to both sides in the near future. Because the intaglio printmaking technique requires extremely expensive, heavy plant machinery and because it requires extremely skilled hand etching of print plates it is very rare for counterfeit banknotes to be produced using this technique. We provide a method and apparatus for detecting intaglio print on banknotes such that potentially counterfeit notes are identified by the absence of intaglio print or the presence of incorrect intaglio print.
Intaglio printing involves making grooves in metal printing surfaces such as copper or zinc plates or cylinders. The grooves are formed in any suitable manner, for example, by etching with acid, engraving or other methods. Typically, fine precision and accuracy is used when forming the grooves making the resulting pattern difficult to replicate exactly. Ink, which is extremely viscous, is applied inside the grooves, for example by covering the printing surface in ink and then removing the ink from all but the grooves. Banknote substrate such as paper is then applied to the printing surface under high pressure (for example, tens of tons of pressure) and the ink is transferred from the grooves or recesses of the plate to the paper. As a result of the high pressure and the viscosity of the ink as well as other factors the regions of paper to which ink is applied are raised up relative to the rest of the paper. This leads to the characteristic “feel” of a banknote which is often used by individuals in a manual test of authenticity of a banknote.
It is not essential for the printed item to be swiped or moved across the sensor in the case that a 2D sensor is used comprising a 2D array of sensor elements. In the case that a linear array of sensor elements is used the printed item may be moved across that linear array to detect intaglio print over a 2D area of the printed item.
The apparatus optionally comprises a heat source 23 of any suitable type such as an electric heating element, heating light source or other heat providing means. The heat source is arranged to provide heat either to the printed item or to the printed item indirectly via the sensor.
The heat source is used to exaggerate the thermal gradient between ridges and grooves of the intaglio print. This enables a better signal to be obtained by the thermal sensor which gives a better signal to noise ratio and improves accuracy.
The apparatus optionally comprises a memory 20 which stores pre-specified information about intaglio printed regions associated with the printed item. This memory may be integral with the apparatus or provided remotely in communication with the apparatus. Alternatively, the apparatus accesses this information from an independent source.
A processor is provided 21 which may be a computer or any other suitable type of processor. This processor is arranged to access the pre-specified information from the memory 20 and to receive sensed information from the thermal sensor 22. It is also arranged to make a comparison between these two inputs and to detect counterfeit printed items on the basis of that comparison. The processor may be arranged to generate an alert in the case that a potential counterfeit is detected. If the processor is provided as part of a self-service apparatus, automated teller machine, or other apparatus the alert may also comprise an action to disable that apparatus.
In one embodiment the pre-specified information simply comprises an indication that intaglio print is expected to be present. The comparison stage may then comprise a simple thresholding process to assess whether the sensed information comprises a signal or only noise. If a signal is present then intaglio print is assumed to be present and the printed item is potentially genuine. Otherwise, if no signal is present, a potential counterfeit is identified.
In another embodiment, the pre-specified information comprises a template or other 2D representation of a pattern of intaglio print expected to be found on the printed item. In this case, the comparison step comprises performing a pattern matching process to compare information about a pattern detected by the thermal sensor with the template. Any suitable pattern matching process can be used such as a correlation process or feature matching process.
In another embodiment (see
a shows a region of a banknote with two ringed regions 3, 4 comprising intaglio print.
In
In another embodiment, in which a heat source 23 is used to apply heat to a banknote immediately prior to presentation to the thermal sensor 22 other regions of the banknote are detected which may not be intaglio printed areas. For example, these are any regions which lose heat at different rates to the air as compared with the banknote substrate. For example, threads, holograms, hot foil stamps, watermarks, or the like. In this case, the pre-specified information preferably also comprises information about thermal sensor profiles for other regions of printed items, besides intaglio printed regions.
The pre-specified information, templates and thermal sensor profiles may be obtained from an independent source or may be created during a calibration type process using printed items known to be genuine.
In some embodiments the apparatus is provided integral with a self-service apparatus or automated teller machine arranged to accept banknotes.
In the example described with reference to
The term ‘computer’ is used herein to refer to any device with processing capability such that it can execute instructions. Those skilled in the art will realize that such processing capabilities are incorporated into many different devices and therefore the term ‘computer’ includes PCs, servers, mobile telephones, personal digital assistants and many other devices.
Some of the methods described herein may be performed by software in machine readable form on a storage medium. The software can be suitable for execution on a parallel processor or a serial processor such that the method steps may be carried out in any suitable order, or simultaneously.
This acknowledges that software can be a valuable, separately tradable commodity. It is intended to encompass software, which runs on or controls “dumb” or standard hardware, to carry out the desired functions. It is also intended to encompass software which “describes” or defines the configuration of hardware, such as HDL (hardware description language) software, as is used for designing silicon chips, or for configuring universal programmable chips, to carry out desired functions.
Those skilled in the art will realize that storage devices utilized to store program instructions can be distributed across a network. For example, a remote computer may store an example of the process described as software. A local or terminal computer may access the remote computer and download a part or all of the software to run the program. Alternatively, the local computer may download pieces of the software as needed, or execute some software instructions at the local terminal and some at the remote computer (or computer network). Those skilled in the art will also realize that by utilizing conventional techniques known to those skilled in the art that all, or a portion of the software instructions may be carried out by a dedicated circuit, such as a DSP, programmable logic array, or the like.
Any range or device value given herein may be extended or altered without losing the effect sought, as will be apparent to the skilled person.
It will be understood that the benefits and advantages described above may relate to one embodiment or may relate to several embodiments. It will further be understood that reference to ‘an’ item refer to one or more of those items.
The steps of the methods described herein may be carried out in any suitable order, or simultaneously where appropriate.
It will be understood that the above description of a preferred embodiment is given by way of example only and that various modifications may be made by those skilled in the art. The above specification, examples and data provide a complete description of the structure and use of exemplary embodiments of the invention. Although various embodiments of the invention have been described above with a certain degree of particularity, or with reference to one or more individual embodiments, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this invention.
