I’m working on a project for a friend where he wants a waterproof button embedded in a bike part. I have a device with some sort of “optical” button where the PCB sits a couple inches away from the case and the “buttons” are just clear acrylic/plexiglass/plastic of some sort. I want to identify the components and try to recreate this circuit if I can, but have had no luck in my previous searches. Don’t know if I’m searching the wrong terms or what. We want to try to use this circuit embedded in an aluminum part, sealed in clear resin, with an acrylic “button” embedded flush with the aluminum surface.

There appears to be a LED or IR emitter, a black chip that looks like it could be a receiver/sensor, and then an 8 pin IC that has “K82 K14 Po” and the “o” is a degree symbol it looks like.

I’d appreciate any help in figuring out what this is. I’m a machinist (run my own business) but I’ve done a lot of electrical and IT work too and did robotics back in school, so I have some idea of how things work. Just can’t find any info on these parts.

And if no one knows what this is, is there another way I can achieve the same result of an “optical button” that works through clear plexi/acrylic? We’re going for a specific look so I really want the plastic embedded flush with the aluminum bracket. I’ve looked at capacitive touch but am unsure as I have no experience with that either.

 

I think what you are looking for is an IR proximity sensor. Not sure how well that work through a plastic window though.

Edited: change detector to sensor

 

Transmissive Sensor with Phototransistor		Product P/N:		TCST1202
Output, 950nm, Daylight Blocking Filter

Do you think something like this would be useful? The output goes high when something blocks the light path. Under US$1 each or free if you are scrapping a laser printer.

 

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Transmissive Sensor with Phototransistor		Product P/N:		TCST1202
Output, 950nm, Daylight Blocking Filter

Do you think something like this would be useful? The output goes high when something blocks the light path. Under US$1 each or free if you are scrapping a laser printer.

I’m familiar with those. Usually have a wheel that spins through it with the little slots in it for speed control/indexing.

That’s not quite what I’m looking for though. I need a weatherproof design and was hoping to be able to not have any moving parts, which would allow everything to be completely sealed and stay weatherproof.

My hope was to glue a 1/2” (12mm) diameter by 1/8” (3mm) thick piece of clear material (plexi, acrylic, etc..) into an aluminum bracket, and underneath it be able to mount a sensor that would act as a switch when someone “presses” the plexi/acrylic.

That is what the circuit in the pictures I posted does with 4 buttons on a SolarEdge inverter. The circuit/sensors sit about 2” from the case, and the case has some sort of clear plastic “buttons” that don’t move, but the sensors can tell which “button” is pushed when you put your finger there. I just don’t know what the components are or how it’s being done exactly. Was hoping someone on here might have some insight.

 

You want a reflective IR proximity sensor.