1838: the first stereoscope
Physicist Charles Wheatstone built the first stereoscope in 1838, using mirrors to present two slightly different drawings to each eye and prove that binocular disparity alone creates depth perception.
The Victorian stereo-card craze
By the 1850s, mass-produced stereo photograph cards and handheld viewers had become a global parlour entertainment, with millions of cards printed of landscapes, cities and news events — arguably the first mass visual media format.
3D cinema's early boom and bust
3D film experiments date back to the 1920s, with a first major commercial boom in the 1950s using anaglyph and polarized glasses, followed by a slower revival in the 2000s and 2010s driven by digital projection.
The VR and spatial computing era
Consumer VR headsets in the 2010s revived stereoscopy as a mainstream technology once again, this time paired with real-time rendering rather than static photography.
Apple's spatial video format and modern glasses-free displays represent the latest chapter: the same 1838 principle, now running through AI depth estimation and micro-OLED panels.
What's stayed constant
Every era swapped the delivery hardware — mirrors, cards, glasses, headsets — but the underlying trick, two offset images fused by the brain, has never changed.
See it in action at 3dstreaming.org