The word “kaleidoscope” literally means “observer of beautiful things” or “an instrument for seeing beautiful shapes,” from the Greek words kalos (beautiful), eidos (shape), and -scope (an instrument for seeing).
The kaleidoscope was invented—and its name coined—by the Scottish scientist and inventor David Brewster in 1815. His invention was wildly popular and sold by the thousands, but before he patented it in 1817, a prototype was shown to opticians in London, who copied it, so Brewster earned nothing almost from the invention.
He also developed a variation on the stereoscope, precursor to the View-Master, which shows a three-dimensional image by depicting two variations on an image for the left and right eye.
Today, the Brewster Kaleidoscope Society, “a society of artists who design and create kaleidoscopes” still bears his name.
Useless Etymology 