Prior Art

A project log for Home Button for Keyboards

Use phone's trackpad as a pointing device.

deʃhipudeʃhipu 06/22/2021 at 17:460 Comments

There is one other attempt at using this kind of sensors that I know of. It's an old post on the Arduino forum, together with a YouTube video with the demonstration, and a few missing images:

In this case a button from Blackberry 8520 was used, which has a very fancy connector, similar to those used sometimes for displays. The sensor itself seems to use SPI protocol and registers very similar to mouse sensors — which makes a lot of sense, since it is basically the same sensor as in an optical mouse, only with different optics and physical shape.