How to create a backlight for a capacitive touch keypad

I'm playing with the MPR121 touch sensor controller demo kit 
from Freescale... and it works :-)

Now I want to assembly a complete capacitive touch keypad that 
can be seen without ambient light, so I'm trying to find a
solution for backlighting.

The keypad should have three layers: the PCB with capacitive pads,
a transparent sheet with a diffuse light and a opaque label 
with transparent symbols what I want show.

What kind of transparent sheet should I use? I think a material
similar to a light pipe that is used to bring the light of a LED
in another place. But I don't know any company that can manufacture 
this kind of sheet. 

Can you suggest someone? I'm going to produce 1000pcs, I don't know
if someone create a custom for me for my project.

On 26/02/2014 5:02 PM, pozzugno@gmail.com wrote:
> I'm playing with the MPR121 touch sensor controller demo kit
> from Freescale... and it works :-)
>
> Now I want to assembly a complete capacitive touch keypad that
> can be seen without ambient light, so I'm trying to find a
> solution for backlighting.
>
> The keypad should have three layers: the PCB with capacitive pads,
> a transparent sheet with a diffuse light and a opaque label
> with transparent symbols what I want show.
>
> What kind of transparent sheet should I use? I think a material
> similar to a light pipe that is used to bring the light of a LED
> in another place. But I don't know any company that can manufacture
> this kind of sheet.
>
> Can you suggest someone? I'm going to produce 1000pcs, I don't know
> if someone create a custom for me for my project.
>


http://www.youtube.com/watch?v=D9ROGEoKVXg

Il 26/02/2014 14:11, Kennedy ha scritto:
>
> http://www.youtube.com/watch?v=D9ROGEoKVXg
>
Very nice, but they manufacture all the system (PCB with capacitive 
keys, light layer and overlay) using a proprietary technology.

I'm interested only in the diffuser plan for the backlight.