Tactile Sensor

[Engauge]

We have an existing indicator light that we would like to add a button function to. I have researched, and experimented with capacitive teouch sensors, which work very well for this particular purpose. The problem is that a gloved hand will not operate a capacitive sensor, and a stylus is out of the question.

A small resistive touch screen would do, but I have yet find any such product on the market. It need only be about 1 inch square, and respond to simple touch/no touch. I am considering making the part myself, but I am not in the habit if reinventing the wheel. Is there an existing product that might work here? Or perhaps there is another method of touch sensor that can be implimented.

An optical approach we suggested, such as an infrared emmitter/detector, but ambient light levels, and packaging contraints have ruled that out.

Any suggestions?

-EG

 

[IRstuff]

Why not a PDA screen?

TTFN

 

[itsmoked]

http://www.eturbotouch.com.tw/main_3_2.asp?pid=14

I'm confused.. You want a non capacitor switch? Or a non capacitive overlay for a screen?

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[Engauge]

Sorry if I wasn't clear. A PDA style (resistive) screen would work fine, but everyting that is currently available ia larger than the form factor we are looking for. Think 1 inch square. Now obviously the technology exists, and it's not very expensive, but to have something with our exact specifications manufactured would be cost prohibitive.

The myriad of capacitive sensors, which can use any substrate as the actual sensor would work exceptionally well in this application except that they don't respond to non-conductive tactile input(i.e. a gloved hand). Form factor isn't a problem though, as we can use the lens of the indicator lamp as the sensor area.

So, I guess what we are really looking for is an off the shelf part that will fit the size requirements in a resistive overlay, or a method to create the same effect, without resorting to having the item custom manufactured, as we only need a few hundred at the most.

EG

 

[itsmoked]

You still haven't cleared me up.. Does the solution have to be see thru?

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[IRstuff]

Densitron makes one that's just barely over 1" square:

http://www.densitron.com/displays/products/?o=1&cat=3&id=11

TTFN

 

[Engauge]

Yes, it does have to be clear. The indicator is a sunlight readable lamp, so a little transmission loss is acceptable though.

IRStuff-
That's getting closer. I'm contacting them to get more information.

If I only had the resources to work with ITO in house, this would be a non issue.

EG