One of the stranger inventions of the 25th century, Hardlight is exactly what it sounds like- light energy, given a material presence. Feeling a lot like lightweight, slightly warm plexiglass, Hardlight can be materialized into virtually any simple shape or form, given any simulated amount of mass and even used to project images or video.
An extremely useful innovation, Hardlight can be found virtually everywhere. It's used for signage, billboards and street-popups; it's used for extendable crosswalks in cities; it's used in common Deck personal computers, forming the keyboard and touchscreen, as well as used as screens projected from TV and Communication decks; it's used in security to create hermetically sealed, damage resistant screens and barriers—force fields, without the force field stigma; it can even be used to create simple hand tools and even melee weapons, like swords and hammers. Basically put, if you can think of it, you can probably make it out of hardlight.