I'm going to make my own version of an optical joystick. The standard design is 4emitters aiming at 4detectors and when the beam is cut (or revealed) that acts as a switch.
There is quite a variety of sensors on different versions of this concept. Not knowing where to start I thought I would copy the one board I have, see photo.
I have found the Sharp GL480 side aiming narrow beam diode which looks like the ones in the picture. But I can't find the detector equivalent, maybe it's just poor searching skills.
Also when searching on IR detector lots of the results have 3 legs, whereas the item on my board is 2 legs. What's the difference? I guess the 3 legged version outputs a signal whereas the 2 legs vary in resistance. Maybe 3 legs is the best way to do it ? The board I have is a replica of an old design, so maybe it it using a slightly out of date technology?
The 3-legged detectors may come from an IR remote control. These sensors include circuitry to detect a 40kHz signal and ignore continuous (ambient...) IR light. Then the big emitters may contain similar circuitry to produce a 40kHz signal? For normal operation LED shaped cases are sufficient for both emitter and detector.
Some IR emitters can be used as detectors as well.
Since starting this thread I have come up with a totally different design idea that will use upward (from the pcb) pointing emitters and receivers.
So I'm no longer searching for the pictured components. Nor am I that bothered about the history. I did find a photo of some even cuter! looking diodes though.. aaawwww pink and blue..
My new problem is I have a big choice of components to ponder over, when I just want to order some and get building a test rig.
