Light and Shadow Bring a New Dimension to Coin Security

Coins have traditionally been viewed as static objects, with their designs and security features visible directly on the surface. A new technology from China Banknote Printing and Minting (CBPM), known as 'floating light mirage', seeks to expand this concept by combining optical engineering, advanced minting techniques and cultural inspiration to create security elements that are revealed through light.

The technology is based on precision microstructures incorporated into the coin's surface. When illuminated at a specific angle with white light, hidden patterns and text are projected onto a nearby surface through reflected light. This creates an additional layer of authentication while introducing an interactive visual effect that differs from conventional security features.

The concept draws inspiration from the ancient art of shadow puppetry, a form of cultural heritage that uses light and shadow to create characters and stories. Shadow puppetry involves stretching a white paper screen over a wooden frame, with a lamp placed behind the screen that casts soft light and shadows through the paper. As the music strikes up, performers manipulate shadow puppets behind the screen.