A tamper-indicating device is described. The device has a transparent or translucent cylindrical body that includes triboluminescent material, and an outer opaque layer that prevents ambient light from entering. A chamber in the body holds an undeveloped piece of photographic film bearing an image. The device is assembled from two body members. One of the body members includes a recess for storing film and an optical assembly that can be adjusted to prevent light from passing through the assembly and exposing the film. To use the device with a hasp, the body members are positioned on opposite sides of a hasp, inserted through the hasp, and attached. The optical assembly is then manipulated to allow any light generated from the triboluminescent materials during a tampering activity that damages the device to reach the film and destroy the image on the film.
This invention was made with government support under Contract No. W-7405-ENG-36 awarded by the U.S. Department of Energy to The Regents of the University of California. The U.S. government has certain rights in the invention.