Thanks. You see I am working on a project that has a motor which drives a piece of paper from point A to point B. The paper will travel through a paper creaser.
The 1mm line is important to ensure that it is perfectly aligned.
I've also read up on IR phototransistors, though not sure whether this would be the best way forward.
Would your suggestions still work based on this scenario?
dougp:
There are multiple ways to detect this.
- detect a lessening of reflected light
- detect thickness of the paper
- detect loss of signal from IR (or other) xmit/rcv pair
What is it you're actually wanting to sense? What's the significance of the black line?