Laptop Touch Pad

[Compass Call]

Touch Pads

Can any of the technically minded among you please explain to me how a Touch Pad works?

I would appreciate an answer in fairly simple terms as I fear that it is one of the 'Black Arts' conjured up by members of 'The Guild of Nerds'.

Thanks in advance.

CC

[fobotcso]

The touch pad contains several layers of material. The top layer is the pad that you touch. Beneath it are layers (separated by very thin insulation) containing horizontal and vertical rows of electrodes that form a grid. Beneath these layers is a circuit board to which the electrode layers are connected. The layers with electrodes are charged with a constant alternating current (AC). As the finger approaches the electrode grid, the current is interrupted and the interruption is detected by the circuit board. The initial location where the finger touches the pad is registered so that subsequent finger movement will be related to that initial point. Some touch pads contain two special places where applied pressure corresponds to clicking a left or right mouse button. Other touch pads sense single or double taps of the finger at any point on the touch pad.

This copied from
HERE (http://searchmobilecomputing.techtarget.com/sDefinition/0,,sid40_gci213159,00.html)

fobs, AMGN (Associate Member of the Guild of Nerds)

[Compass Call]

fobotsco


Thank you for the plain English explanation - very much appreciated.

I do hope that you don't get into trouble with your Guild Fathers for telling the secret behind the 'Black Art':E

CC

[Saab Dastard]

Just think, 15 years ago a "laptop touch pad" would have been the item on spot that you could touch the top of someone's thighs when in the seated position.:hmm:

How times change.

OK, it's a wet and miserable Sunday afternoon!:O

SD

[Hersham Boy]

Does this explain why it actually has to be a finger? ie. a pencil tip won't do the same job...

[fobotcso]

'Welcome CC.

The finger, or other body part, will have electrical properties that inert objects such as pencils won't. Those properties might include electrostatic charge and capacitance. It's these that proximity switches use for the control of machinery etc.

[Tinstaafl]

My laptop has a more complicated touchpad, marketed as the 'C-pad'. It includes an underlying LCD screen so images can be displayed.

Regions associated with the image(s) can be assigned functions & tasks eg scrolling, opening programs, even a calculator & signature reader.

Under Linux I've even seen it receive & display system information such as CPU load, batter level etc. Very nice!

[Ray Darr]

I have a Synaptics cPad on my Toshiba laptop and really enjoy it. I've had no major issues with it. In fact, the applications that are launchable within the "pad" itself are handy - calendar, calculator, sticky-note, etc. The only one I dislike is the signature-capture. As mentioned above, pens, etc, do not work. You ever try to sign your signature with YOUR finger-tip? Besides this annoyance, it's been great. (Any "signature" suggestions out there, cPad users??!)

Options with the cPad include "Tap-and-Drag" (which I dislike mainly because I think mine hasn't been set up properly...or this may just be a flaky feature that I found not user-friendly), plus "Palm-Check" where if you accidentally place your palm on the pad it ignores that), and also vertical and horizontal navigation drag-bars (which are very handy when moving around on web-pages). It also has zoom and pan abilities, but I haven't tried, or even programmed them "on" yet.

One other option the cPad has is to display dual time-zones. I have it always showing the local time where we reside, and the home-town's local time. Handy when deciding to make a phone call, etc.

There are applications that can be launched within the cPad that are either downloadable or programmable...neither I have gotten, so I cannot comment on this feature (I'd like to try some things, though, but just haven't located any worth getting yet!) Also you can put custom logo's or photos (grey-scale) too, but once again I haven't tried this.

Strangely, the cPad isn't on current Toshiba laptops I see for sale, even though this has been a great product (9.7 / 10 IMHO).

Synaptics, the maker of the cPad, even has a speaker-pad product (no comment as I haven't used it).

Here is a good cPad "how it works" site:
http://www.synaptics.com/technology/tcps.cfm

Cheers,
R.D.

[Tinstaafl]

Ray Dar, that's what I & Pax D have on our laptops. Bloody brilliant! We really like the cPad thing.

[Ray Darr]

Has anyone have much success locating useful add-on programs for the cPad?

(One I wish I had was a selectable backlight-on / off option!)

Cheers,
R.D.

[Tinstaafl]

It's do-able in Linux. The catch is that the light has a limited life - something like 3 or 4000 hrs.

[Ray Darr]

Excuse the Linux lack of knowledge...but will a Linux script and/or program work within the Windows OS environment?

I would like to locate some programs for this cPad, and if any are in Linux that are usable in Windows that would be good...if they don't work I will stay on my quest.

Thanks for the cPad light life-info, Tinstaafl.

R.D.