Normally, we skip covering patents here at Android Police. Most of them never materialize in a product and "what if" games are just conjecture. However, a recently published patent application by Google has caught our eye for the unique and slightly ridiculous way it aims to hide a camera beneath a smartphone display. When was the last time you saw a magic show?
It's a little more than a sleight of hand trick, but Google's patent application for a "full-screen display with sub-display camera" (which is still pending, and was filed in 2019) describes a mirror-based system that allows a single hole in a display to pass light for both a camera and a second screen hidden behind the exterior display, via a change in angle for that mirror. There are a few ways to arrange things geometrically, but the animation above (created from the patent application itself) shows a hole in the display directly above a mirror, which can rotate or flip between two different angles. One angle allows the camera to see through that hole, the other reflects the light from the second screen to basically "fill" the hole as far as your eyes are concerned.
Samsung also patented a similar method with a physically moving secondary display that slides in and out of position to cover a camera.
It's pretty wild, and kind of ridiculous. There are a lot of reasons why this approach is impractical, and I'm almost entirely sure this will never manifest in a product.
For one, the difference in depth between the second screen and the outer display will cause issues for both focus when you are close to the display, and result in some depth-based parallax/alignment problems unless you're looking at the display head-on from a decent distance. Second, unless this hole and mirror are pretty large, the in-display camera will probably have a very tight field of view through the hole.
Current solutions for in-display cameras don't suffer from either of these problems, though they have their own other issues that this approach would fix. Contemporary designs use either "transparent pixels" which aren't actually that transparent and can diminish light-gathering ability, or they use a patterned cathode that allows light to travel through the screen between the grid of pixels. In both cases, these designs introduce unwanted optical effects that can cause images to be soft or misty-looking, and a hole with a mirror wouldn't suffer from either.
This isn't going to land in your next Pixel — or, I'm guessing, any future phone. But it's pretty wild in a sort of Rube Goldbergesque way, and fun to think about.