Maker Thomas Poll is building a Raspberry Pi Pico-powered keyboard with a difference: every key on the board has its own independently-addressable OLED display panel, allowing for unlimited customization.
“The Poly Keyboard […] speaks any language with OLED displays in its keycaps,” Poll explains of the project. “[It’s a] polylingual keyboard with tiny little OLED screens in each keycap to display just any language(s) you need. Of course, it can do even more.”
The Poly Keyboard aims to put a user-addressable OLED display under every single key. (📷: Thomas Poll)
The current design of the board uses a split ergonomic layout with the primary keys arranged in mostly-ortholinear columns and housed in two separate board halves connected by a keyboard — though Poll explains that “any keyboard layout is possible,” from ultra-compact macro pads to traditional 100 per cent layouts.
What ties every layout together is its flexibility: a display on each key allows for the board’s logical, though not physical, layout to be revised at any time. Switching between languages in software will be reflected in the legends displayed on the keys — while they’re also capable of showing icons representing application-specific actions or shortcuts.
The board is powered by a Raspberry Pi Pico and its RP2040 dual-core microcontroller. (📷: Thomas Poll)
Poll’s keyboard design originally centered around an STMicroelectronics STM32F407. “When I started, the STM32F407 was cheap, fast, and had plenty of IO [Input/Output] pins and, therefore, [was] an ideal choice, I thought. Now you have to pay 40 bucks for the dev board I used and as I’m trying to make a dev kit out of this project I need some more accessible components.”
The solution was to join a growing number of makers shifting to the Raspberry Pi RP2040 microcontroller, which remains available in ready supply for $1 or less per chip. “The [Raspberry Pi] Pico (with an RP2040) comes at a price of 4 Euro [around $4],” Poll explains.
The concept of putting a display in every key isn’t new. In 2005 design house Art. Lebedev Studio showed off its Optimus design, a traditional full-size keyboard layout which — just like the Poly keyboard — packed an OLED display under every key, before the company switched to a cheaper variant which used a single large LCD and transparent keycaps. The core idea, though, dates back to a 1978 IBM bulletin and Hewlett-Packard patent which would inspire student Reinhard Engstler to design the LC Board in 1984.
Poll intends to produce the Poly Keyboard as a developer’s kit, enabling people to customize its capabilities and layout as desired — though during this prototyping stage is keeping most information about the project on his Ko-Fi page, with design file to be uploaded to GitHub “once reaching a more ‘production ready’ state.”