Holography and the spirit of the dance.
It was around this time that Steve McGrew and Gil Colgate at US Banknote, and Sal D' Amato and Ed Weitzen at American Banknote, recognizing the fascination of holographic imagery combined with the difficulty in creating it, had the idea of using it as a security feature on documents.
In this edition of Holography News, we report a presentation given by Dr Glenn Wood on behalf of the International Hologram Manufacturers Association (IHMA) to the Pan European High Security Printing conference held in Berlin, Germany, this month. The presentation charts the adoption of holograms on banknotes from the first images to appear on Austrian and Australian notes in 1988 to the most recent versions being produced in Japan and Germany.
From Simplicity to Complexity
Throughout most of those 20+ years, the holograms (more correctly Diffractive Optically Variable Interference Devices--DOVIDs) have been surface-relief devices manufactured by embossing or casting, then metalizing, to give metallic stripes and patches reflecting irridescent rainbow colors. From the simple image of Captain Cook on the commemorative Australian $ 10 note, the origination technology increased in sophistication leading to the highly complex graphics exemplified by the Kinegrams on Euro banknotes.
These holographic images are supposed to be overt, Level 1 security features permitting even the general public to distinguish between the genuine and the counterfeit. However, the transition from a wall hanging to a small element on a piece of paper (or plastic) destroyed the 'dance'. Display holograms are viewed under carefully controlled lighting conditions in which the angle between the light source and the image is fixed and predetermined. The same is also true of the viewing angle and the hologram was originated in the first place assuming a head on viewing position. All this goes out of the window when the hologram is small and hand held, often viewed n poor lighting condition that don't lend themselves to optimal replay.
No Rules for Viewing
The task of viewing such images is exacerbated by the lack of rules relating to their appreciation. Some need to be rocked from side to side whilst others are tilted backwards and forwards. Still others should be rotated to cause one image to flip to another. Whilst every effort is usually made to print leaflets, posters and other educational material, there is no denying the difficulty in educating an entire population as to what they should be seeing and what movements they need to carry out to see it.
Thus we discern two developments which may become trends. First is the development by Regula in Belarus of a compact little 'spectral luminescent magnifier' which takes all the guesswork out of inspecting security holograms. In effect, it leaves the general public out of the equation and puts into the hands of authentication specialists a tool with built in light sources and computer software which automatically confirms whether the hologram is what it is supposed to be, or not. (See next issue for full details of Regula's tools.)
The second is the development of robust photopolymeric recording materials that allow the mass production of volume holograms suitable for use in document security. This material is likely to make its first appearance on Swiss banknotes in the near future and will present an appearance unlike any other seen until now. The flashy rainbow colors will no longer be in evidence. Animation effects will be seen as the notes are moved in a fairly intuitive way and the colors will be the fixed monochromes--reds, greens and oranges- seen on volume holograms years ago. In the case of these images, produced by OVD Kinegram, there will be no depth, just 2D animation.
DNP Turns the Clock Back
Alternatively, Dai Nippon Printing is turning the clock back to the times of early display holography and seems determined to give us what we naturally associate with holograms, namely full parallax imagery. DNP will also undertake stereograms retaining depth but sacrificing vertical parallax but, on a Lippmann medium, the rainbow effects of the Benton transmission are not apparent.
This is good news for those artists and graphic designers who have worked with volume media for so many years. Maybe their visions, ideas and experience will now be appreciated and used directly in a security context. The developments in digital examination are not such good news, however, because they minimize the value and importance of human interaction. We, at Holography News, welcome all innovation connected with holograms but we especially like the 'dance'. Anything that people do naturally and out of fascination has a potency that survives long after the power fails and the batteries expire.