The leading high resolution multi-spectral imaging system for questioned documents
The NEW VSC 6000/HS desktop video spectral comparator is a comprehensive digital imaging system providing the questioned document examiner with an extensive range of facilities for detecting irregularities on altered and counterfeit documents.
The VSC 6000/HS is equipped with a high-resolution colour camera and zoom lens, a range of viewing filters, and multiple illumination souces from UV to visible to IR wavelengths. Instrument functions are selected and controlled through a simple graphical user interface and the Windows operating system includes casework management and image archiving facilities. An integral microspectrometer allows measurement of reflectance, transmission, and fluorescent features.
NEW features added to the VSC6000/HS include:
A method of optimizing the spectral differences between two different inks on a document.
Birefringent Security Features
A new circular polarizer will image security features printed with chiral birefringent pigments.
Multiple Laser Images
Multiple Laser Images (MLI) and Changeable Laser Images (CLI) can be viewed using either the VSCs side lights or hologram imaging LEDs
Deciphers 1D and 2D barcodes including PDF417 format.
A digital imaging filter detects and enhances latent security images on documents.
- NEW Hyperspectral Imaging
- NEW Birefringent security feature visualisation
- NEW Multiple laser image visualisation
- NEW 1D and 2D barcode reader
- 5.0 million pixel FireWire camera for high resolution imaging.
- spectral range of 360 to 1100nm
- 'HFi' technology for improved image quality.
- 30” (75cm) wide screen monitor for improved image display.
- On-screen magnification up to x170 (+/- 6%).
- field of view from approximately 2.5x1.9mm to 210x160mm
- maximum resolution of 28536 pixels per inch.
- on-screen note pad for report writing.
- image database search facility with keyword search engine.
- 'thumbnail' gallery for viewing casework images.
- ROI 'Region of Interest' image processing – improves the effects of image enhancing software.
- differential absorption imaging - amplifies small differences in the spectral absorption characteristics of inks.
- fully integrated high resolution, real-time grating spectrometer with 9nm resolution.
- wide field, broad band infrared illumination for examining anti-Stokes fluorescence.
- full range of light sources including incident, oblique, and transmitted, from UV to IR
- 14 LED scanning array providing sequential visualisation of OVDs with video recording facilities.
- designed for easy servicing and lamp replacement plus automatic lamp failure diagnostics.
- e-passport and ICAO card reader.
A method of optimizing the spectral differences between two different inks on a document.
● Image cube creation over adjustable wavelength range from 400 to 1000nm.
● Incremental steps from as low as 1 to 4nm (depending upon spectral range and PC memory capacity) up to 20nm
● Spectra of any points on the image immediately available for comparison
● Image cube and spectra may be saved and recalled
● Simple calibration procedure
● Enables the operator to scroll through the image set in real time to obtain the maximum spectral difference
1D and 2D barcode reader decodes barcodes present on passports from countries including Pakistan, Canada, Romaina, and Ghana.
Deciphered encrypted information includes: Name, passport, DOB, date of issue etc.
A new circular polarizer in the VSC®6000/HS will image security features printed with chiral birefringent pigments which appear to contrast against the background under the polarizer.
Multiple Laser Images (MLI) are images engraved beneath the surface of the document by laser that produce 'flipping pictures' when illuminated with light from different angles. Although similar to holograms, MLIs offer higher security as they cannot be removed in the same way as can traditional holograms. The new VSC6000/HS is designed with a range of side lighting to detect and display these images.
Above Image: Concealed information(top) becomes visible by absorbing the infrared fluorescence emitted by the masking ink(bottom)
Concealed information on a document may be revealed by examining the document under visible or near infrared light. A number of effects may be exploited:-
- If the masking ink is transparent to near infra red light and the underlying ink is opaque, the underlying information will be revealed using either incident or transmitted infra red light and a suitable infrared high pass filter.
- If the masking ink is slightly transparent to visible light and the underlying ink is photoluminescent, the masked information may be revealed by illuminating the document with intense visible light, some of which will penetrate the masking ink to induce the underlying ink to fluoresce. Although very weak, the fluorescence signal may be integrated to produce a strong legible image.
- If the masking ink is fluorescent and the underlying ink absorbs the fluorescence the underlying information may be revealed by examining the document under intense visible light.
Above Image: Infrared fluorescence emitted by the concealed ink is sufficient to penetrate the masking ink when illuminated by intense visible light. The weak emission is integrated until visible
This is normally a straightforward process of examining a document with transmitted light but examinations may be made easier with a variety of additional techniques.
For example, it is possible to eliminate printing or handwriting on the surface of the document that is masking the watermark by examining the document in the infra red rather than the visible. Alternative display modes, in which original and counterfeit images are superimposed or displayed side by side, also make comparisons easier.
Above Image:A Portugese visa under longwave UV showing fluorescent features
Special features which are invisible to the eye but which fluoresce brightly under ultraviolet light are often printed on or incorporated into security documents to deter counterfeiting. The VSC 6000 provides a range of UV lamps to examine these features. In addition to visual examination, fluorescence spectra and colour co-ordinate measurements can be made on samples as small as 62 microns square.The VSC 6000 features the following UV sources:
- long wave incident UV, 365nm peak wavelength
- medium wave incident UV, 312nm peak wavelength
- short wave incident UV, 254nm peak wavelength
- long wave transmitted UV, 365nm peak wavelength
Above Image:Dutch passport under normal lighting(top)- Dutch passport showing retro-reflective features under co-axial lighting (bottom)
Retro-reflective features are elaborate graphic designs that are incorporated into security documents to prevent counterfeiting. They are printed with special coatings that render them invisible under normal light and can only be seen with illumination that is precisely coaxial to the angle of view. The VSC 6000 provides the appropriate lighting and imaging systems to enable these features to be examined and printed.
Above Image:A Chinese banknote showing the security features printed with anti-Stokes inks and illuminated with infrared light.
The VSC 6000 provides infrared illumination above 800nm that is free of visible light, making it possible to examine security features on documents and identity cards printed with anti-Stokes security inks. These inks have been designed to fluoresce in the visible region of the spectrum when illuminated with infrared light.
Above Image:An OVD on a 500 euro banknote (above) viewed with angled illumination and a series of different OVD images on a 5 euro banknote(top)viewed using sequential, multi-angled illumination.
OVDs on security documents commonly exhibit different images when illuminated at different angles. The VSC 6000 is fitted with 14 white LEDs in horizontal and vertical arrays to provide sequential illumination at varying angles of incidence. The multiple images comprising the OVD may be stored and displayed without tilting the document.
Inks on a document that are identical in colour but have different chemical compositions may provide evidence of an alteration when examined in the near infrared region of the spectrum. Although undetectable with the naked eye, a near infrared image is easily converted into visible one, using an infrared sensitive video imaging system such as the VSC 6000. Two techniques may be used.
The first is to look for differences in the near infrared light reflected or transmitted by the two inks. The document is illuminated with either incident or transmitted broadband infrared illumination and examined through a range of long wave pass filters with increasing thresholds between 650nm and 1000nm. Any difference in the spectrum of the transmitted or reflected light will become evident under at least one of the filters.
The second is to look for differences in the photoluminescence or fluorescence emitted by inks and, again, this is normally observed in the red to near infrared region of the spectrum. This fluorescence may be generated by illumination with intense visible light that has been filtered free of near infrared. As before, an examination of the document is conducted through a range of long wave pass filters with increasing thresholds between 650nm and 1000nm. Any difference in the spectrum of the fluorescence will become evident under at least one of the filters.
The VSC 6000 provides the examiner with the sensitive infrared imaging system and the light sources and filter sets to perform both types of examination. Image integration is also provided to enhance the fluorescent images which are often of very low intensity.
The VSC 6000 features orthoganol oblique lighting, illumination from two light sources at different angles, that provide the examiner with a clearer image of indented writing or embossed stamps.
However, not all such examinations are straightforward, as the presence of printing or handwriting on the document may interfere with the image and hinder examination. When the ink causing interference is transparent to near infrared light, it can be eliminated by conducting the examination at this wavelength. After the VSC 6000 converts the infrared image to a visible one the ink will appear to vanish while the infrared shadow remains. The VSC 6000 enables such examinations to be made at wavelengths in the near infra red up to 1000nm.
Although the shadow casting technique is useful for examining deep indentations and embossing, shallow indentations or those not visible at all, are more effectively examined using an electrostatic imaging technique.
See details of the company's product ESDA².
Graphic designs and logos on original documents and product labels are often inaccurately reproduced on counterfeits. These inaccuracies are easier to detect by examining original and counterfeit either side-by-side or by superimposition at high magnification.
Matching tear profiles between fragments of paper is another example where the VSC 6000 can be effective. If the image of one fragment is stored and displayed as a virtual object, it can be superimposed on the real image of a second fragment without the fragments coming into contact. This prevents distortion of the edges as one fragment is moved relative to the other.
A range of comparative display modes are available on the VSC 6000 as standard.
One of the simplest ways to detect a counterfeit document is by visual comparison with a genuine one. With the VSC 6000's wide display screen, high resolution and zoom magnification up to x140, discrepancies in fine detail are easier to detect when documents are displayed side by side. Both images can be annotated with text and symbols and both have notepads attached on which observations can be jotted down.
Above Image:The colour co ordinates of six blue inks displayed on a chromaticity diagram
Colour co-ordinates are a useful way of defining colours and provide a convenient way of recording and comparing colours objectively. The VSC 6000 enables colour to be measured in both the standard 1931 and 1960 CIE colour co-ordinate systems.
Colour co-ordinates can be displayed on chromaticity diagrams which provide effective graphic evidence of colour differences, especially when the colours of many samples need to be compared. Colours, which differ in intensity only, have co-ordinates that lie on a common colour radial. Colours with true spectral differences lie on different colour radials.
Both colour coordinates and chromaticity diagrams may be stored in the VSC 6000's casework filing system for future reference.
The VSC 6000 enables four types of spectra between 400 and 1000nm to be measured - absorption, reflectance, transmittance and fluorescence. These may be used as further aids in the identification of counterfeit documents.
Absorption and reflectance spectra are measured with reference to a standard white tile to provide absolute measurement. Transmission spectra are measured with a dual beam system for normalisation. Fluorescence spectra are measured without a reference signal, and are therefore subject to the spectral characteristics of the camera and lighting. Weak fluorescence may be integrated by up to 10 seconds before analysis, considerably enhancing the sensitivity of the spectrometer in this application.
The VSC 6000 also provides a number of facilities for processing spectra; normalisation, to eliminate the effects of a background to allow spectra on different substrates to be compared; subtraction, to highlight differences in spectra and differentiation to identify wavelengths of greatest change.
Spectra may be retained in document records under the VSC 6000's general casework management system.
With high resolution imaging the VSC 6000 enables the operator to display up to 60 stored images on a single screen to provide a quick method of retrieving a stored image.
Above Image:In this case a clear difference in area of 0.26mm2 detected
Measuring specific features of a document often provides valuable evidence of a counterfeit. The VSC 6000 enables the radius, length, angle and area of a feature to be measured using an on screen cursor. Calibration provides absolute measurements and the instruments high magnification range allows the smallest features to be examined.
'Quick Check' is a new feature of the VSC 6000 that enables an operator to make a sequence of document examinations under a variety of fixed, pre-programmed instrument settings. The facility is designed to standardise the repetitive examination of large numbers of similar documents such as passports, ID cards or cheques, suspected of being altered or counterfeited.
Once programmed under Quick Check, the VSC 6000 automatically adopts the mode of illumination, lamp filter, imaging filter and lens magnification appropriate to the examination task selected, minimising operator performance errors.
Each stage of a multi-task examination sequence can be initiated either manually or automatically. Under automatic operation, each instrument setting is maintained for a predetermined period of time to allow the operator to carry out the examination before moving on to the next stage. Reports may be filed for future appraisal by a supervisor or expert examiner.
The technique can save time, ensure consistency in procedure and is particularly suitable for use by technician operatives.
The VSC 6000 features an optical character reader that allows the operator to examine the ICAO coded data in the machine readable zone of passports and ID cards.
Once the operator has selected the appropriate country from the menu, the OCR deciphers, checks and displays the information held in the machine readable zone of the document under the instrument.
Personal information invisibly embedded in photographs has become a valuable technique for protecting passports and ID cards against forgery. To visualise the information the operator simply selects a country to automatically apply the appropriate decoder. The system covers most systems currently in use and new ones can be added by the operator as they arise.
The VSC 6000 enables the operator to create comprehensive casework files, in which images, spectra, chromaticity charts, notes and observations may be stored. Images have associated instrument settings, i.e. type of illumination used, camera filter, integration time and magnification, which enable the operator to recreate identical conditions when making subsequent document examinations.
Images may be annotated with text and symbols and each is provided with an on-screen working notepad for the operator's convenience while conducting an examination. All stored images, charts and spectra and associated notepads may be interfaced with Microsoft Word for report writing.
Image search facilities allow the operator to retrieve stored images by name, file type (i.e. Tiff, BITMAP, JPEG, etc), keyword with wild card and by approximate date of entry (between two dates). A pull-out gallery of all recently stored images provides a short-cut to image retrieval and to browse all images stored in a casework folder, a thumbnail gallery will display 60 images at a time.
High resolution CCD firewire colour camera with 360 to 1100nm spectral response
Zoom magnification range of approximately x1.5 to x170 (+/- 6%) on the standard 75cm (30inch) display monitor
Fields of view: 2.5x1.9mm to 210x160mm
Imaging filters: 15 high pass filters in the visible and near infra red with thresholds at 530, 550, 570, 590, 610, 628, 648, 668, 690, 715, 725, 780, 823, 856 and 1000nm plus a broadband pass filter 390-610nm
Modes of illumination:
- long wave UV, incident lighting (365nm)
- long wave UV, transmitted lighting (365nm)
- medium wave UV, incident lighting (312nm)
- short wave UV, incident lighting (256nm)
- visible and infra red, incident lighting
- visible and infra red, transmitted lighting
- visible and infra red, oblique lighting
- visible coaxial incident light (for examination of retro-reflective security features)
- narrow bandwidth illumination, 100W tungsten halogen lamp with a 400 to 1000nm continuous interference filter operated in 1nm steps with average bandwidth of 40nm
- Horizontal and vertical arrays of LED lamps for sequential scanning of multiple image OVD's
- High intensity infra red illumination for the excitation of anti-Stokes inks
- High intensity incident spot light, 250W tungsten halogen lamp with independent low pass and high pass filters providing 80 different wavebands and zoom lens, providing a broad beam to a focused spotlight
Image integration, on-chip with integration periods of 8ms to 180s in 33 steps
Colour measurement, provides CIE colour co-ordinates & chromaticity diagrams - measures colour parameters: XYZ, xy, uv, Lab. Displays data on 1931 and 1960 UCS chromaticity charts
Microspectrometry measures absorption, reflectance, transmission and fluorescence spectra. 400 to 1000nm range, with a resolution of 9nm FWHM.
PC system operating Windows XP/Vista/7 Network capability
ICAO data reader
Embedded personal information decoder
Casework management software which enables images, examiner's notes and other instrument derived data, such as spectra and diagrams, to be stored in casework files. Images may be annotated and stored with instrument settings
Image processing software providing:
- Side by side comparison of live and stored image
- Superimposition of a live and a stored image with adjustable mix, 0 to 100%
- Variable speed image strobe between a live and a stored image
- Left to right image reversal (horizontal mirror reversal)
- Top to bottom image reversal (vertical mirror reversal)
- Grey level reversal (positive to negative)
- Image rotation, through any angle
- Contrast stretch
- De-speckle filters (noise reduction)
Image measurement software providing:
- Distance between two points
- Area within a user defined box
- Radius of a circular feature from three peripheral points
- Angle between two lines
- Area of user defined shape
- Area of selected features, i.e. an alphanumeric character or logo
Controls via graphical user interface
Universal power input, 85-250V, 50/60Hz, 700W
Document capacity: Accommodates documents up to 596x422mm
Nikon SMZ 1000 Stereo microscope with phototube, 2 x objective, 10 x eye pieces and multi – directional LED illumination
Nikon SMZ 1500 Stereo microscope with phototube, 2 x objective, 10 x eye pieces and multi – directional LED illumination
Nikon SMZ 645 Stereo microscope with 1.5 x objective
Leica M125 Microscope with phototube, 2 x objectives, eye pieces, transmitted light base and LED multi-angle sidelight and coaxial incident illumination
Leica M205C Microscope with phototube, 1 x objective, eye pieces and multi – angle LED illumination
Leica DVM2000 Digital video microscope
Translation stage An XY translation stage is now available for the VSC®6000 document examination system to allow precise positioning of a document at high magnification. The stage is manually adjustable, with a travel of +/- 20mm in both X and Y directions, and is transparent from long wave UV to near infrared to facilitate transmitted light examinations. The translation stage can be easily fitted to the VSC®6000 by the operator.
E-Passport & ICAO Reader Desktop e-document reader for reading ISO14443-4 documents such as electronic passports and identity cards with a Machine Readable Zone or ICAO coded data.
Embedded personal information decoders Software to detect and display imbedded personal information on passports and ID cards, including pre-sets for different passports (and ability to save future settings).
Identity document database A reference database of over 1,400 passports, driving licences and identity cards from 180 countries. Data includes descriptions and over 20,000 images of watermarks, holograms and UV features. Information is supplied on DVD by annual subscription with updates issued monthly.
Banknote database A reference database of over 4,500 banknotes from 180 countries. Data includes over 70,000 images and descriptions of watermarks, holograms and UV features. Information is supplied on DVD by annual subscription with updates issued monthly.
Auxiliary video microscope An imaging system that provides an additional high magnification input into the VSC®6000 software. The microscope package includes 5 Mpixel high resolution colour camera, Leica M205 microscope with phototube, LED illumination.
Magnetic security feature imager Optional USB device for magnetic ink profiling
Quartz glass holding plate A quartz glass plate to hold documents flat during examination. Transmittance greater than 80% from 250-1100nm. Dimensions: 200mm x 200mm x 6mm with polished edges
Invisible information (IPI and ICI) decoders Software to display embedded IPI (Invisible Personal Information) and ICI (Invisible Constant Images) on pasports and ID cards. Uses Scrambled Indicia Technology supplied under licence from Graphic Security System Corp.
Polarisafe viewer UV polarised light viewer for VSC6000/HS (specifically to view Swiss passports.