Lippmann OVD Hans I. Bjelkhagen Hansholo Consulting Ltd www.hansholo.com Lippmann January 2004

Recording Materials Panchromatic isochromatic materials required Low light-scattering emulsions needed Ultra-high-resolution materials Possible materials: Silver halide emulsions Photopolymer materials Lippmann January 2004

Lippmann OVD Passport Tests DuPont photopolymer material was used Laminated to sputtered silver foil Recorded passport samples Lippmann January 2004

Dark slide with photopolymer film laminated to reflecting sputtered silver foil Lippmann January 2004

Optical Security for Documents Iridescence – the fluctuation of colours in otherwise colourless matter – has become a cornerstone of optical document security Iridescent phenomena comprising: Interference Diffraction Thin films Multilayers Gratings Holograms Lippmann photographs Various optical security devices are now common on different types of documents such as banknotes, passports, driving licenses, credit cards, etc. Such devices are commonly referred to as Optical Variable Devices (OVDs) R. L. van Renesse, Ed., Optical document security, 2nd ed. Artech House, Boston, London (1998) Lippmann January 2004

OVD on Austrian Banknote Lippmann January 2004

OVDs on Credit Cards VISA, MasterCard, American Express and many other cards have embossed holograms attached as OVDs Lippmann January 2004

The Lippmann OVD The Lippmann photograph represents a new type of OVD It belongs to the : Interference Security Image Structures (ISISs) Lippmann January 2004

The Lippmann OVD for Enhanced Document Security Lippmann photograph attached to a security document Lippmann OVD Security document Perpendicular observation Oblique observation Lippmann January 2004

Old Swedish passport tests Original Lippmann OVD Lippmann January 2004

Lippmann OVD Details Lippmann January 2004

Swedish Passport Lippmann OVD Negative OVD Tilted OVD Lippmann January 2004

The Latent Intaglio Print Image “SVERIGE” (Sweden) on the top of the Swedish Passport: Revealed when obliquely observed (upper right) Also recorded in the Lippmann OVD (lower right) Lippmann January 2004

US Passport sample with Lippmann OVD Lippmann January 2004

US Passport with Lippmann OVD Switching between a Positive and Negative Image Lippmann January 2004

Lippmann OVD Display Device Passport sample with a Lippmann OVD attached in the upper left corner. Light from a diffuser above the passport makes it easy to inspect the Lippmann OVD laminated to the passport. Lippmann January 2004

Cards for military personnel, police officers, custom inspectors, etc. The Lippmann OVD is only of interest for documents individually issued, such as: Identification cards, e.g., corporate ID cards (air pilot’s ID cards, nuclear power plant employees) Cards for military personnel, police officers, custom inspectors, etc. Travel documents (e.g. Shengen visa) Driving licences Passports Credit cards Lippmann January 2004

Advantages over embossed holograms A Lippmann OVD can be individually made A unique label for each document The issuer of the document can produce them in-house The Lippmann OVD has a very high archival stability The Lippmann OVD is Bragg sensitive The Lippmann OVD can record latent images The Lippmann OVD cannot be copied by conventional colour photography, colour scanners or colour copy machines Lippmann January 2004

Publications on Lippmann Photography applied in the field of document security: H. I. Bjelkhagen, “New optical security device based on one-hundred year old photographic technique,” Opt. Eng. 38, 55-61 (1999) H. I. Bjelkhagen, “A new OVD based on interferential photography recorded in holographic materials,” in Proc. SPIE 3638, 87-95 (1999) H. I. Bjelkhagen, “Lippmann Photography: A highly innovative OVD based on existing photographic techniques,” Keesing's Journal of Documents 1, Issue 2, (2003) Lippmann January 2004

Contact Details Dr Hans I. Bjelkhagen www.hansholo.com Email: hansholo@aol.com www.hansholo.com Lippmann January 2004