Some digital projectors can produce 281 trillion shades of colour. That's approximately 40 thousands colours for each and every person on Earth. What makes them work is theoretically simple, but the technological feat requires extreme precision in practice.
The guts of these projectors consist of a prism that splits light into red, green, and blue wavelengths. Each of these three broad spectrums gets directed towards its own microchip, which is covered in millions of incredibly small mirrors attached to microscopic hinges. The mirror positions determine how much red, green, or blue is present in each of pixel, and your eyes (and brain) do the rest. It's a familiar concept, but the scale and accuracy of high quality digital projectors make the final effect astonishing.
Precise colour comes at a price, though: like their analogue counterparts, digital projectors produce an incredible amount of heat. To prevent components from being damaged — or melting — each of those microchips has its own spiky-looking heatsink, and an array of fans pushes hot air out of the machine. For added safety, pumps send liquid coolant through tubing inside the projector, wicking away even more heat.
Devices like these are commonplace and easy to take for granted. But just remember then next time you're at the movies: millions of mirrors are working hard so you can watch Chris Evans beat up Robert Downey Jr.