Opto Photo Interrupter with LM393 and potentiometer

Other Hardware Hardware Development
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I see that there are available opto photo interrupters that you can get by themselves to interact with an arduino (such as ITR9608F). These, by themselves seem to interface to an analog pin.

I also see photo interrupters combined with LM393 comparators that have 3 or 4 pins. 3 pins usually only digital out, 4 pins with digital and analog out.

I wanted to use the 3 pin model that is combined with an LM393 for my project. My problem is, there is no way (that I can find) to set the "sensitivity" of the diigital output. That is to say, how opaque must the light blockage be to trigger a digital interrupt.

I see lots of other analog sensors combined with LM393 IC's that also have a potentiometer to adjust sensitivity on them. Sush as avoidence sensors and sound sensors. I can't find a sensor with a Opto Photo Interrupter with LM393 and potentiometer.

If someone can point me to one that would be great. If not, can someone help me with a schematic of how I might combine the 3 together?

Tekrantz (first time poster)

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Most of the photointerrupter modules detect whether the light beam is completely blocked or not, nothing inbetween.
If you want something based on opacity, you will need to build your own.

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Something like this will work. The voltage divider R2/R3 sets the trigger level and could be a potentiometer.

You could also adapt one of the sound/proximity sensor boards that already have a pot. Remove the parts you don't need and connect the opto-interrupter to the comparator input.

Capture

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Thanks, I had thought about getting a sensor with the pot already in it and cutting off/replacing the part with my interrupter but am glad to get a second opinion. I will certainly try that as well as the circuit above.

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