Diffractive optically variable image device

Last updated

A diffractive optically variable image device (DOVID) is a type of optical variable device; a security feature based on visual effects created by diffraction. The acronym was coined by Ian Lancaster of Reconnaissance International in 1995. [1] He pointed out that the security print industry was wary of holograms and similar diffractive devices because they were used as decorative, promotional and toy items, proposing the use of DOVID as a means to differentiate security diffractive optical devices from these other uses.

Contents

DOVIDs are incorporated in government-issued documents of value (banknotes, passports, visas, identification credentials and driver licenses) to increase their counterfeit resistance. [2] [3] Brand protection is another application of DOVIDs. DOVIDs contain micro- or nanostructures in the form of diffractive gratings. Due to these structures, they exhibit optically variable effects such as dynamic chromatic, holographic, and kinematic effects, two- or three-dimensional images or color-changing effects, which ideally are easily recognized, but are difficult to reproduce. Well known examples of DOVIDs are holograms such as 2D or 3D or 2D/3D holograms based on mask illumination, dot matrix or e-beam origination technology and Kinegrams. [4] [5] [6]

A DOVID can also contain elements which are invisible to the unaided human eye such as microprint, kinetic microtext, or a variable laser-readable micro-image that is invisible when magnified under white light. DOVID structures can be incorporated in a foil: which is then hot stamped on a paper document (e.g., banknote, visa), incorporated within the structure of a polycarbonate or composite card (e.g., passport, driver licenses) before personalization or integrated in a laminate that is heat sealed to the surface of a card after personalization (e.g., driver licenses, identity cards). [7]

Specific types of DOVIDs

DOVID types can be categorized as follows: [8] [9]

Transparent: This DOVID feature consists only of dielectric material, typically including a high-refractive index material (HRI), and therefore is highly transparent. An underlying image or print may be seen clearly. Depending on the angle of view, the DOVID reveals an optically variable image. Transparent DOVIDs can be applied in patch form or as a laminate covering the entire surface of the substrate, e.g. the paper-based data page of a passport. This type of DOVID is not well suited for protecting banknotes due to the moisture sensitivity of the HRI material, but they are widely used for securing some government-issued identity documents.

Metallized: This DOVID is opaque, exhibiting a fully metallized (mostly aluminum coated) diffractive image with optically variable effects. Fully metallized DOVIDs are typically applied in patch or stripe form. They are, for example, used for protecting paper-based documents, such as birth certificates or land titles. In the late 1980s and early 1990s, this type of DOVID was also used on banknotes.

Partially metallized: This DOVID contains a combination of opacity and transparency on the same surface. The originally fully metallized image is selectively de-metallized to emphasize specific texts or other sub-structures, and to create patterns or specific shapes by the metallization. For over thirty years, this type of DOVID has been used to protect banknotes and applied in patch or stripe form.

Hybrid or Combi: This DOVID contains two or more interrelated visual areas, such as partially metallized and transparent, but revealing continuous visual effects for authentication. The combination of both (partially) metallized and transparent high-refractive index coatings in one feature is more complex than only transparent or only partially metallized features and requires more sophisticated production techniques, thus making it more difficult to counterfeit.

Precision Metallized: A precision metallized DOVID is composed of fine-line diffractive images which are accurately registered to the metallization. The tolerances are much tighter than with conventional partial metallization. Typical designs include metallized guilloche patterns with clearly defined movements and fully transparent intermediate areas (i.e., with no diffractive structures) revealing the underlying document or banknote security print. The precise, tightly toleranced registration between the diffractive images and the metallization makes it harder for counterfeiters to mimic the DOVID appearance.

Incorporation of DOVIDs in documents

DOVIDs are applied either during the manufacturing process of the documents or at the document issuing office.

For banknotes, DOVIDS are applied to the paper or polymer surface (as a patch or stripe) or incorporated as a windowed security thread. In most cases, some form of security print is applied over portions of the DOVID to integrate it into the document (layered security) and make counterfeiting more difficult. [10]

For paper-based identity documents (visas and passports), DOVIDs are either incorporated prior to personalization in the same manner as for banknotes (visas) or, as a full-face laminate after personalization (passport data pages). For incorporation of DOVIDs prior to personalization, a security print is usually applied over portions of the DOVID to integrate it into the document (layered security). [11]

For plastic-based (e.g., polycarbonate, Teslin, and composites) identity documents (identity cards, driver licenses and passport data pages), DOVIDS are often embedded within the card body during card layer collation and lamination process. This adds durability and increases security while enabling complex interaction with security features on other layers of the card (layered security). In rare cases, DOVIDs are applied on the plastic surface similar to paper-based documents. [12]

Related Research Articles

<span class="mw-page-title-main">Holography</span> Recording to reproduce a three-dimensional light field

Holography is a technique that enables a wavefront to be recorded and later reconstructed. It is best known as a method of generating three-dimensional images, and has a wide range of other uses, including data storage, microscopy, and interferometry. In principle, it is possible to make a hologram for any type of wave.

<span class="mw-page-title-main">Lamination</span> Technique of fusing layers of material

Lamination is the technique/process of manufacturing a material in multiple layers, so that the composite material achieves improved strength, stability, sound insulation, appearance, or other properties from the use of the differing materials, such as plastic. A laminate is a layered object or material assembled using heat, pressure, welding, or adhesives. Various coating machines, machine presses and calendering equipment are used.

<span class="mw-page-title-main">Security printing</span> Field of the printing industry for banknotes and other security products

Security printing is the field of the printing industry that deals with the printing of items such as banknotes, cheques, passports, tamper-evident labels, security tapes, product authentication, stock certificates, postage stamps and identity cards. The main goal of security printing is to prevent forgery, tampering, or counterfeiting. More recently many of the techniques used to protect these high-value documents have become more available to commercial printers, whether they are using the more traditional offset and flexographic presses or the newer digital platforms. Businesses are protecting their lesser-value documents such as transcripts, coupons and prescription pads by incorporating some of the features listed below to ensure that they cannot be forged or that alteration of the data cannot occur undetected.

<span class="mw-page-title-main">Security thread</span> Security feature of banknotes

A security thread is a security feature of many banknotes to protect against counterfeiting, consisting of a thin ribbon that is threaded through the note's paper.

<span class="mw-page-title-main">Identity document forgery</span> Fake IDs and their production

Identity document forgery is the process by which identity documents issued by governing bodies are copied and/or modified by persons not authorized to create such documents or engage in such modifications, for the purpose of deceiving those who would view the documents about the identity or status of the bearer. The term also encompasses the activity of acquiring identity documents from legitimate bodies by falsifying the required supporting documentation in order to create the desired identity.

<span class="mw-page-title-main">Kinebar</span>

A kinebar is a gold bar that has a diffractive optically variable image device embossed into the surface of the gold. The device used is a "Kinegram" made by OVD Kinegram AG (Switzerland). The Kinegram technology is exclusively provided to governments, and is intended both as a high-security feature and for visual appeal.

<span class="mw-page-title-main">Brazilian identity card</span> National identity card of Brazil

The cédula de identidade is the official national identity document in Brazil. It is often informally called carteira de identidade, "RG" or simply identidade in Portuguese. The card contains the name of the bearer, filiation, place of birth, date of birth, signature and thumbprint of the bearer. Other national documents can legally be used as an identity card, such as a federative unit-issued driver's license, passport or, for minors, a birth certificate. Each card has a unique RG number. As of 11 January 2023, the CPF number will be used as the RG number on new identity cards.

<span class="mw-page-title-main">United States passport card</span> U.S. identification card

The United States passport card is an optional national identity card and a travel document issued by the U.S. federal government in the size of a credit card. Like a U.S. passport book, the passport card is only issued to U.S. citizens and U.S. nationals exclusively by the U.S. Department of State. The passport card allows its holders to travel by domestic air flights within the U.S., and to travel by land and sea within North America. However, the passport card cannot be used for international air travel. US passport cards are used to verify identity and US citizenship. The requirements to attain the passport card are identical to the passport book and compliant to the standards for identity documents set by the REAL ID Act.

<span class="mw-page-title-main">Croatian passport</span> Passport of the Republic of Croatia issued to Croatian citizens

Croatian passport is issued to citizens of the Republic of Croatia for the purpose of international travel. The passport has the purpose of serving as proof of Croatian citizenship and identity. Responsibility for their issuance lies with the Ministry of the Interior; and for citizens abroad, passports are issued by the local embassy or consulate. Croatian passports are valid for ten or five years, and are not renewable. Every Croatian citizen is also a citizen of the European Union. The passport, along with the national identity card allows for free rights of movement and residence in any of the states of the European Economic Area and Switzerland.

<span class="mw-page-title-main">Greek passport</span> Passport of the Hellenic Republic (Greece) issued to Greek citizens

Greek passports are issued to Greek citizens for the purpose of international travel. Biometric passports have been issued since 26 August 2006, with old-style passports being declared invalid as of 1 January 2007. Since June 2009, the passport's RFID chip includes two index fingerprints as well as a high-resolution JPEG image of the passport holder. From 18 December 2023 the issuance of new generation of Greek passports started by selected authorities and after 9 January 2024, only the new generation of passports are issued. Every Greek citizen is also a citizen of the European Union. The passport, along with the national identity card allows for free rights of movement and residence in any of the states of the European Union, European Economic Area, and Switzerland.

<span class="mw-page-title-main">Security paper</span>

Security paper is a paper used in security printing that incorporates features that can be used to identify or authenticate a document as original, e.g., watermarks or invisible fibres in paper, or features that demonstrate tamper evidence when fraud is attempted, e.g., to remove or alter print such as amounts or signatures on a cheque. Examples of this kind of papers are used for banknotes and used for identification such as passports and certificates, such as birth certificates and different types of academic and qualification certificates, as well as government documents, e.g., voting ballots and tax strips. This also extends to personal and business checks, stock certificates, certificates issued by financial institutions and sensitive government-issued documents. The main use of security paper is to stop people from counterfeiting.

<span class="mw-page-title-main">Albanian passport</span> Passport of the Republic of Albania issued to Albanian citizens

The Albanian passport is a travel document issued by the Ministry of Interior to Albanian citizens to enable them to travel abroad. They are also used as proof of identity within the country, along with the Albanian ID card.

<span class="mw-page-title-main">Security hologram</span> Security label

Security holograms are labels with a hologram printed onto it for sale security reasons.

<span class="mw-page-title-main">German identity card</span> German identity document

The German Identity Card is issued to German citizens by local registration offices in Germany and diplomatic missions abroad, while it is produced at the Bundesdruckerei in Berlin.

<span class="mw-page-title-main">Documento Nacional de Identidad (Argentina)</span> National identity card of Argentina

Documento Nacional de Identidad or DNI, is the main identity document for Argentine citizens, as well as temporary or permanent resident aliens. It is issued at a person's birth, and must be updated at 8 and 14 years of age, and thereafter every 15 years. It takes the form of a card, and is required for voting, payments, military service inscriptions and formalities. They are issued by the National Registry of Persons (RENAPER).

Specialized Enterprise Holography Ltd. (SE Holography) is a company that specializes in production of holograms and holographic security elements. Holography, a member-company of the EDAPS Consortium, is among the founders of the security printing industry in Ukraine. Established in 2000 with the support of the International Centre the Institute of Applied Optics on behalf of the National Academy of Sciences of Ukraine. Holography Ltd. is a member of the International Hologram Manufacturers Association (IHMA), a member of the International Society for Optical Engineering (SPIE) and a member of the Counterfeiting Intelligence Bureau at the International Chamber of Commerce of Ukraine.

<span class="mw-page-title-main">Optical variable device</span>

An optical variable device or optically variable device (OVD) is an iridescent or non-iridescent security feature that exhibits different information, such as movement or colour changes, depending on the viewing and/or lighting conditions. The particular changes of appearance when rotating and tilting are reversible, predictable and reproducible. OVDs cannot be photocopied or scanned, nor can they be accurately replicated or reproduced. OVDs are often used as security devices and anti-counterfeiting measures on banknotes, government-issued identification documents, or credit cards. OVDs can be created through a combination of printing and embossing.

<span class="mw-page-title-main">Greek identity card</span> National identity card of Greece

The Greek identity card is the official national identification document for Greek citizens. It is issued by the Hellenic Police.

Kinegram may refer to:

<span class="mw-page-title-main">Plastic card</span>

Plastic cards usually serve as identity documents, thus providing authentication. In combination with other assets that complement the data stored on the card, like PIN numbers, they also serve authorization purposes, most often as bank cards for allowing their holders to do financial transactions. Early and simpler cards feature only hard-to-imitate integrated photographs, security holograms, guillochés, or a magnetic strip on which few bytes of personal data could be stored. Today, smart cards, i.e. those equipped with an electronic chip, serve as high-security active electronic documents that allow their holder to qualify for driving cars, receive medical treatment, do banking and more.

References

  1. Lancaster, Ian (1995). Diffractive Optically Variable Image Devices. Intergraf International Security Printers Conference. Lisbon.
  2. Stole, Svorad; Soukup, Daniel; Huber-Mörk, Reinhold (September 2015). "Invariant characterization of DOVID security features using a photometric descriptor". 2015 IEEE International Conference on Image Processing (ICIP). pp. 3422–3426. doi:10.1109/ICIP.2015.7351439. ISBN   978-1-4799-8339-1. S2CID   12289666.
  3. "Document Security Alliance (DSA)". Archived from the original on 2011-06-29. Retrieved 2021-05-05.
  4. "Council of the European Union – PRADO – Public Register of Authentic Identity and Travel Documents". Archived from the original on 2016-09-24. Retrieved 2021-05-05.
  5. van Renesse, R. L. (2005). Optical Document Security. Boston, London: Artech House.
  6. Cabral, Alexandre; Rebordão, José M. (2011-07-26). "Diffractive optical variable image devices generated by maskless interferometric lithography for optical security". In Costa, Manuel F (ed.). International Conference on Applications of Optics and Photonics. Vol. 8001. International Society for Optics and Photonics. p. 800121. Bibcode:2011SPIE.8001E..21C. doi:10.1117/12.890750. S2CID   108645721.
  7. "Technical terms related to security features and to security documents in general" (PDF). Archived (PDF) from the original on 2015-09-24. Retrieved 2021-05-05.
  8. "Innovative protective foil elements with Kinegram". www.kinegram.com. Retrieved 2022-09-07.
  9. "Diffractive Features on Banknotes Special Report". International Hologram Manufacturers Association. 2018-08-24. Retrieved 2021-05-05.
  10. "Kinegram Technology". www.kinegram.com. Archived from the original on 2021-05-05. Retrieved 2021-05-05.
  11. "Passports". www.kinegram.com. Retrieved 2021-05-05.
  12. "ID and DL Cards". www.kinegram.com. Archived from the original on 2021-12-01. Retrieved 2021-05-05.