Holo

How this works (and why it's not "real" plasma)

This is Pepper's Ghost — a 19th-century theater illusion repurposed for phones. Each pyramid face is a 45° half-mirror. The screen shows four views of the same 3D object around its center. Each face reflects its quadrant inward, your eyes combine all four reflections into a single shape floating above the apex.

Why a phone can't make a real mid-air hologram

A literal volumetric image — light hanging in empty air with nothing reflecting it — needs one of:

• Plasma in air — femtosecond lasers focused to ~10¹⁴ W/cm² ionize air molecules into glowing voxels. (Aerial Burton "Fairy Lights", 2015.) An iPhone LED is ~13 orders of magnitude too weak.
• Photophoretic trap — a single dust particle held in mid-air by laser pressure, painted by RGB lasers, scanned faster than your eye can resolve. (BYU Optical Trap Display, 2018.)
• Volumetric persistence — a fast-rotating helical screen with synced LEDs. (VOXON, late 2010s.)
• Fog projection — project onto an actual physical medium (mist, scrim, water droplets). The "hologram" lives on the medium.

What you actually have here

A real shape made of light, suspended visually above the phone — but the photons are bouncing off pyramid walls, not floating freely. Walk around it; it tracks correctly. Best in a dark room. Bigger pyramid + brighter screen = more impressive.

If true mid-air projection is what you want next, the cheap path is a fog/mist projector — short-throw projector aimed at a thin laminar fog wall. Real images, no glasses, no pyramid.