The Quest for the Perfect Keyboard Continues

Don’t ever bring up the topic of keyboards around a group of techies unless you want to instantly find yourself in a heated discussion. Opinions about the ideal style of keyboard, or the best switches or keycaps to use, vary wildly, and every single person present will be absolutely certain that their preferences are objectively the correct choices.

That means a keyboard would need to be almost infinitely configurable to make everyone happy. That is a tall order, but it hasn’t stopped people from trying to build such a device.

Perhaps the most obvious solution is to use a touchscreen display. But while these do offer unlimited flexibility, the typing experience itself is absolutely terrible. As a compromise, keyboards have been developed with a tiny display in each individual keycap. This would be a great solution if it wasn’t so pricey. These keyboards often sell for well over a thousand dollars.

To keep costs down, some people have attempted to put transparent keyboards over the top of touchscreens. But while the typing experience with these keyboards is better than a bare touchscreen, it still isn’t very good.

YouTuber Inkbox thought that using a single screen was the right direction to go, but was unhappy with the typing experience of these keyboards, so he decided to build his own custom solution. After giving the problem some thought, he decided to embed small magnets in the side of 3D-printed resin keys. By also embedding magnets in the supporting structure of the keyboard, the clear keys could resist being pressed down, like standard keys.

So far so good, but there also needed to be a mechanism to read out key presses. The magnets pulled double duty here. Hall effect sensors were embedded in a circuit board beneath the screen. When the keys are pressed down, it changes the strength of the magnetic field that these sensors detect.

These measurements were passed through analog-to-digital converters before being read by the GPIO pins of an Orange Pi 5 single-board computer. Software running on this computer interprets the signals to determine which key was pressed, and it sends that information to a connected computer, which sees it as an HID device.

With the nuts and bolts of the device in place, all that was left was to display an image on the keyboard’s screen. By lining the image up with the keys, any arbitrary letters or graphics can be displayed under each one. There is also some room between and above the keys that can be used to display additional graphics just for fun.

In the end, despite all the effort, this keyboard still just wasn’t that great. The keys were a bit undersized, and because of the magnetic mechanism, they tended to shift around slightly. It looks like the search is still on for the perfect keyboard.