If you lift an optical mouse off its normal surface, you could put a finger underneath, against the optical sensor, and by moving your finger affect the mouse-cursor on the screen.

If that sensor is built into the keyboard, then you don't have to move your hand from the keys very far to reach the sensor, so that you can move a finger and thereby move the mouse cursor on the screen. This is more like a touch-spot than a touchpad --but that just means it could more-easily fit somewhere in in a keyboard.

To reduce any visual annoyance, because the mouse sensor normally works in conjunction with a red light that illuminates the surface upon which the mouse is moved, we can use an infrared light source for this Idea. It won't be visible, but should work just fine.
-- Vernon, Apr 22 2016

Buy one now for $5.99 + free shipping http://www.amazon.c...8-001/dp/B003R9NL5W
[scad mientist, Apr 22 2016]

Wouldn't be much in the way of resolution, but sounds like it'd beat the hell out of touchpads. [+]
-- FlyingToaster, Apr 22 2016


Resolution isn't the problem so much as range. A tiny motion of the finger needs to move the mouse-cursor only a small distance; you would lose fine control if cursor moved far. So, that means a larger motion of the finger moves the finger completely off the sensor, before the cursor moves a large distance on the screen. That's the main reason why this Idea is HalfBaked.

On another hand, a modestly larger sensor area on the keyboard surface could be made to allow control of the cursor over a decent portion of the screen. To move the cursor the rest of the way (say from one side to the other of the screen), lift finger from sensor so it is out- of-focus, move finger back to other edge of sensor, touch the sensor and move finger in same direction as before. Some folks do something similar already with ordinary touchpads (because of how the touchpad- resolution is set), so this is not a huge thing to ask.

The above could also work with a smaller sensor, but you would have to lift and move your finger more often. I suppose some experimentation is in order, to find the most reasonable compromise between sensor size and number of separate finger-motions.
-- Vernon, Apr 22 2016


I always hated the little j-cursors that became the norm on laptops for awhile; horrid little things that bent your fingers sideways. I don't think this would be much better due to the awkward action of moving your fingers in ways the joints aren't supposed to go.
-- RayfordSteele, Apr 22 2016


The sensor needed for this is baked, widely known to exist (among RIM Blackberry users), then discontinued ~2012.

Google Blackberry Optical Trackpad. I never heard anything but positive reviews about it. It used a an infrared laser. It was essentially the same system used in laser mice.

Get yours now for $5.99 before supplies run out. See link.

Putting it on a laptop or desktop keyboard sounds like a fine idea to me.
-- scad mientist, Apr 22 2016


Come to think of it my old HTC phone had something similar.
-- RayfordSteele, Apr 22 2016


I have been considering including such a device in my laptop ergonomic keyboard project, so you might see something like this implemented some time somewhat soon or not-so- soon.
-- notexactly, Apr 22 2016



random, halfbakery