"I myself feel that our country, for whose Constitution I fought in a just war, might as well have been invaded by Martians and body snatchers."
- Kurt Vonnegut, Jr.

"Walls, Lydia, remember; crystal walls, that's all they are. Oh, they look real, I must admit - Africa in your parlor - but it's all dimensional, superreactionary, supersensitive color film and mental tape film behind glass screens. It's all odorophonics and sonics, Lydia...

To learn more about how the modern, multimedia home entertainment system has evolved in the minds of great science fiction writers, be sure to see dimensino - alien entertainment center from Time is the Simplest Thing by Clifford Simak (1961) and rifle range - virtual skeet shooting designed by aliens from Way Station also by Simak (1963).

An interesting contrast can be made to The Veldt, which is designed as an immersive environment, but is still outside the person who is using it. Contrast The Veldt with simstim - play back your internal experience from the 1984 novel Neuromancer by William Gibson, and XV wedge - Photoshop for your mind from Mother of Storms by John Barnes (1994). Both of these authors offer purely internal experience as entertainment. Your mind is, after all, the ultimate source of your personal entertainment.

Bradbury actually described this idea a year earlier in There Will Come Soft Rains:

Four-thirty.

The nursery walls glowed.

Animals took shape: yellow giraffes, blue lions, pink antelopes, lilac panthers cavorting in crystal substance. The walls were glass. They looked out upon color and fantasy. Hidden films clocked though the well-oiled sprockets, and the walls lived. The nursery floor was woven to resemble a crisp cereal meadow. Over this ran aluminum roaches and iron crickets, and in the hot still air butterflies of delicate red tissue wavered among the sharp aroma of animal spoors! There was the sound like a great matted yellow hive of bees within a dark bellows, the lazy bumble of a purring lion. And there was the patter of okapi feet and the murmur of a fresh jungle rain, like other hoofs falling upon the summer-starched grass. Now the walls dissolved into distances of parched weed, mile on mile, and warm endless sky. The animals drew away into thorn brakes and water holes.

It was the children's hour.

He also used it in The World the Children Made published in The Saturday Evening Post the same year:

(Bradbury: The World Children Made)

Now the hidden odorophonics were beginning to blow a wind of odor at the two people in the middle of the baked veldtland. The hot straw smell of lion grass, the cool green smell of the hidden water hole, the great rusty smell of the animals, the smell of dust like a red paprika in the hot air. And now the sounds - the thump of distant antelope feet on grassy sod, the papery rustling of vultures. A shadow passed through the sky...

"They almost got us!"

"Walls, Lydia, remember: crystal walls, that's all they are. Oh, they look real, I must admit; Africa in your parlor, but it's all dimensional superreactionary, supersensitive color film and mental-tape behind glass screens..."