A pen whose ink answers to light.
To the eye it writes in ordinary black or blue. Inside, two ink reservoirs feed one tip at the same time, so every stroke carries a crystal that glows under ultraviolet and a second one that glows under infrared.
- Two inks, one stroke. Separate compartments dispense together, mixing UV and IR crystals in every line.
- A code in the ink. The color, rise time and decay of the glow can encode an identifier, even a player’s jersey number.
- A lightmap in every signature. Reflective flakes land at random as you write, so no two signatures share the same pattern.
- Black ink without carbon. Carbon black blocks infrared, so the ink is formulated to let the light through.
- Checked by a reader. An IR VCSEL and UV light in a small reader, or a phone, read the ink, then log the time and place to a blockchain-secured record.
- A forensic layer too. A nanocrystal marker in the ink adds a third check for the lab.
Spark Labs reader
One handheld with both lights. It fires a short pulse of ultraviolet, then a pulse of infrared, again and again, and watches each glow rise and fade. Only Intelligent Material answers both lights, in the right colors, with the right timing. The glow is shown slowed down about a thousand times: the real reader takes a fraction of a second.
Plain-language summary of the published application. It is not yet a granted patent, and the claims may change before one issues. Illustration only.
Inside the pen
Two crystal inks. One tip.
Cut the barrel open and the trick is plain to see. Each reservoir carries its own crystals, and both feed the same tip, so every stroke of a signature holds both. In daylight they look like ordinary ink. Switch the light and each set answers in its own color.