Category Archives: multitouch hacks

Hacking Touch Screens to Count Pulses

Heart rate sensors available for DIY use employ photoplethysmography which illuminates the skin and measures changes in light absorption. These sensors are cheap, however, the circuitry required to interface them to other devices is not. [Petteri Hyvärinen] is successfully investigating the use of capacitive touchscreens for heart rate sensing among other applications.

The capacitive sensor layer on modern-day devices has a grid of elements to detect touch. Typically there is an interfacing IC that translates the detected touches into filtered digital numbers that can be used by higher level applications. [optisimon] first figured out a way to obtain the raw …read more

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Posted in capacitive touch, display, heart rate, misc hacks, monitor, multitouch hacks, screen, sensor | Leave a comment

A Huge Infra-Red Touch Board

We’re all used to touch pads on our laptops, and to touch screens. It’s an expectation now that a new device with a screen will be touch-enabled.

For very large surfaces though, touch is still something of an expensive luxury. If you’re a hardware hacker, unless you are lucky enough to score an exceptional cast-off, the occasional glimpse of a Microsoft PixelSense or an interactive whiteboard in a well-equipped educational establishment will be the best you’re likely to get.

[Adellar Irankunda] may have the answer for your large touch board needs if you aren’t well-heeled, he’s made one using the …read more

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Posted in ir, IR touch, led hacks, multitouch hacks, pointing device, touch surface | Leave a comment