The current sensor board is build in the following way: TSL235R light to frequency converter, RGB and IR leds are sunk in hotglue. I know it's not the good way (it's extremely uncomfortable as you can imagine)... But I needed a quick solution because I was curious what will it give as result.

The sensor is pretty big itself, it's because it is based on through-hole technology elements (let's say it's not easy to buy SMD components where I live). On the beginning I wanted to solder them on a custom made board, but following image will explain right away why I didn't, just look at the thickness of that thing...

Even knowing it's not very pretty and certainly not comfortable, it gave some pretty interresting results. For example I was trying to verify if I can detect if the sensor is attached to the skin or if user moved it letting incident light come in. Just have a look at the following figure:

Approximately at the 150 iteration hotglue sensor was in the peak of not being attached to the skin, we can see how light converges into single point that represent natural day white light.

That would be all. It's not very recent study, but the problem of building a better sensor is still essential. I'm looking for an easy and cheap way to connect LEDs and TSL235R together the way it would be light proof and comfortable, any ideas are welcome.

Cheers!