By: Rebecca Johnson, Preservation Specialist & Offsite Storage Coordinator
Sometimes wanting to display an artifact for the public to experience and wanting to preserve it for posterity is a hard balance to find. Light is a source of damage to artifacts and the effects are irreversible. In the Postal Museum’s new exhibit, Behind the Badge, which opened June 2014, the staff decided to display two extremely light sensitive artifacts: a letter and envelope from the 2001 anthrax attacks and a detonator from a 1920s train robbery. Normally, both objects, if put on display in regular exhibit cases, would only be allowed on display for a few months; otherwise light damage would eventually cause irreversible fading. The objects would then have to be stored in dark cabinets for safe keeping by the Collections staff. The only way the public could see them would be through pictures, which is never the same as seeing the real thing. The museum wanted the public to enjoy viewing the artifacts for as long as possible, so the Preservation staff began researching solutions to help mitigate the light damage problem. They found VariGuard SmartGlass™.
The SmartGlass™ is an amazing innovation in glass technology that allows light to reach an artifact only when it is being viewed. This extends the amount of time the object can be on exhibit because it is not getting unnecessary light, allowing more people to see prized artifacts in the museum’s collection. The two exhibit cases with SmartGlass™ in Behind the Badge use push-buttons to activate the glass and lights in order to see the anthrax letter and the detonator. Visitors can hold the button as long as they like to view the object and when they release the button the glass goes dark again.
How does it work? There is a film laminated between two pieces of glass that contains nano-scale particles. When the push-button is not engaged, the particles scatter, making the film go dark, thereby creating a barrier against the light. When dark, the SmartGlass™ blocks 99.5% of the visible light. When a visitor pushes the activation button, an electric current is sent into the film, the particles align and allows light to pass through the glass. The size and shape of the glass can be customized to fit any size exhibit case, which makes it ideal in any museum environment.
Now that the SmartGlass™ has reduced concerns about artifacts receiving any unnecessary light, the anthrax letter and the detonator will be on display for much longer than the three months originally planned for them. Working with the SmartGlass™ is new territory for the Preservation staff and they are closely monitoring and researching the impact this new technology has on how long it extends the time artifacts are on exhibition. At present, they do not have an answer as to how long the objects will now be on exhibit. When the Preservation department has their results, they will let everyone know.