Data crystals known as Optical Information Crystals were developed by the Galactic Empire as a way to conceal vital intel from the Rebel Alliance throughout the duration of the Galactic Civil War. These are discussed in more detail at data crystals.
These particular crystals required activation using a strong beam of light, achievable through the use of a laser light generator. Furthermore, a sizable tilting mirror was essential to accurately guide the laser beam's path onto the crystal's surface.
The creation of Optical Information Crystals occurred during the Galactic Civil War, a conflict between the Rebel Alliance and the Galactic Empire. Around the time of 0 ABY, several Optical Information Crystals ended up in the possession of the Nkik clan of Jawas. They were stored within a stronghold located on Tatooine, carefully monitored under the eye of an individual named Keemee.