hey there,
i opened a old tv remote. I noticed that the buttons are different to what i have seen so far. There is a silicon layer. When i press a button the layer will be bend so it touches a pattern on the circuit board.
Here is also a photo:
what are these pads/ patterns called?
Thank you!
Membrane keypads, among other things.
There's probably a black spot on the underside to connect the traces on the PCB.
It's been called many things, try looking for conductive carbon buttons or some combination of conductive/dome/carbon/silicone/squishything.
It's pretty low tech stuff, just open traces that detect when they're connected. A moist finger would work or a piece of metal, conductive thread, whatever. The dome gives some tactility, but more importantly has a layer of carbon on the underside to do the conducting.
Some people call them capacitive buttons, but that's typically used to refer to the ones without a mechanical button.
Would you like to hear some of the things I've called them when trying to repair?....NAH >:(
My first memories of such buttons were on a Betamax player
Silicon and silicone are two different things. I do not think that you are seeing a "silicon layer."
Tom, Dick, & Marvin?
They are elastomeric keypad buttons. The typically gold plated traces on the PCB get shorted by a small carbon pad on the underside of the button cover. If you ever need to clean them, isopropyl alcohol or non- residue contact cleaner work really well. DO NOT USE AN ABRASIVE !! Hope that info helps !!