At the point in time the Walt Disney Company patented the multiplane camera, Walt had long since stopped getting his hands dirty with drawing or technology.
Wikipedia's page on the multiplane camera is interesting: https://en.wikipedia.org/wiki/Multiplane_camera
The first incarnation: Lottie Reininger/Carl Koch, 1926. Lottie's "Adventures of Prince Achmed" from the same year is the oldest known surviving animated feature, and can be watched in its entirety on Wikipedia.
Other people fooled around with the idea but there's nothing wiki-notable.
1933: while estranged from Disney (it's a long saga), Walt's former star animator and Mickey co-creator Ub Iwerks built a more advanced one.
1934: the ever-inventive Fleischer studios (inventors of the process of 'rotoscoping', where animators trace over live action) took a very different approach to the problem of creating a sense of depth in animation and built their bugfuck insane Stereoptical Camera, which put miniature sets on a turntable, with a place to put animation cels (which, tangentially, were invented back in 1914 at Bray Studios).
1937: Disney's studio put together a seven-layer multiplane camera for Snow White. Walt's name went on the patent.
(When I was a kid dreaming of being in the animation industry in the seventies, Leonard Maltin's Of Mice and Magic was the canonical history of the entire medium, if you're curious about the minutae of long-vanished studios. It's a lot easier to actually see any old piece of animation that you're curious about than it was back then.)