3D photo technology for secure driver licenses
11 January, 2010
category: Biometrics, Government, NFC
By Cindy Alexander, Identity Solutions Manager, MorphoTrak
Three-dimensional photo technology strikes the delicate balance necessary for driver licenses between ownership, privacy, ease of enrollment and cost. This technology provides a first-line security feature that is obvious at a glance and simple to validate.
Laser-engraved 3D portrait technology is difficult to counterfeit and inherently establishes ownership between the ID and its rightful owner. The method used to validate the 3D photo security feature is clear and performed intuitively by examining the image. It is intrinsic to the person being identified and integral to the card structure.
Verification does not depend upon a myriad of first- and second-line features that vary from state to state and can be difficult to check without specialized training or equipment. This 3D technology works with equipment most people have–eyes and a brain that views slightly different images from each eye stereoscopically to create 3D images. Cardholder privacy rights are enhanced with a known and obvious feature–photos–available on all drivers’ licenses. 3D photo enrollment is as simple, fast and non-invasive as typical photo capture and offers the advantage of using low-cost, off-the-shelf components.
Figure 1 : The capture of the four photographs
To create a high quality three-dimensional image of the license holder, four photographs of the holder are taken simultaneously, from slightly different angles. The eyes are used as a reference point by the software for fitting the images over one another prior to the laser engraving process. The slight difference in angles between the four photographs created can be seen by comparing the ears in each photo from left to right.
The polycarbonate card body provides a medium that can be layered for different purposes while providing a finished card that cannot be separated. Polycarbonate layers cannot be separated because the layer binding process combines the molecules of the material to create a single of hard, durable card. Figure 2 shows the different layers including a laser sensitive layer in which the image will be engraved.
Figure 2: Polycarbonate card body consisting of a (a) transparent top layer, (b) laser sensitive layer with a print and an Integrated Diffractive OVD on it, (c) white pigmented core layer with a print on the reverse side (d) a transparent back layer
The lamination process involves melting the polycarbonate sheets between two heated plates. The various layers are inextricably bound after this process, by entanglement of the polymer molecules, so that they cannot be separated or spliced without destroying the card.
Figure 3: Cross section of a lenticular lens array covering the surface of a polycarbonate ID card captured using a scanning electron microscope
A lenticular lens array is created during the lamination process, using a hollow cavity. The four portrait images are laser engraved, each with a different angle, into the lens array.
When viewed through this lens array, the left- and right eye will each view a different laser engraved photo when inspecting the document. The brain then converts these individual images into a three-dimensional portrait.
This method allows the perfect registering of the images and the lenses. The fine line structure of the laser engraved 3D image provides an image far superior to typical photos and makes counterfeiting virtually impossible.
Three-dimensional photo technology can stand alone to secure documents or work with other first-, second-, and third-line features. It can be combined with other optically variable effects using lenticular lens structures, such as adding letters to the four images. The letters appear to “float above” the card surface while the photograph “sits beneath” the surface. Since both these first-line features are easily recognized, they add further ID security while staying consistent with established industry practice. 3D photo technology provides a powerful first-line feature for drivers’ licenses that easily integrates with existing workflows and security concepts used.
About the AVISIAN Publishing Expert Panel
At the close of each year, AVISIAN Publishing’s editorial team selects a group of key leaders from various sectors of the ID technology market to serve as Expert Panelists. Each individual is asked to share their unique insight into what lies ahead. During the month of December, these panelist’s predictions are published daily at the appropriate title within the AVISIAN suite of ID technology publications: SecureIDNews.com, ContactlessNews.com,CR80News.com, RFIDNews.org, FIPS201.com, NFCNews.com, ThirdFactor.com, and DigitalIDNews.com.