Home made optical rencoder issues

[Elnino]

Ok, so i stuck one of my disks under the microscope and to be honest they look pretty darn good! The toner is solid and the edges are a little 'furry' but only about 1 micron (1/1000mm) is furry. I doubt many commercial encoders would be much better.

There were a couple of sub micron holes but this particular disk had not been cared for - it was one of my test ones. I doubt they would have any effect anyway.

So, where does that leave me? Well, it means doubling the disks is probably pointless but making the clear slots smaller might be of some help. I sincerely doubt that a 1 micron 'edge' is going to cause a problem for a sensor that is likely to have a beam width of probably at least 10 times that.

[Elnino]

Ok, so i've managed to have a bit of a play with my encoders - hardware and software and managed to get it 'smooth'.

I changed from disks with 6deg clear and 6deg black to 2 and 10deg. This made a big difference but did not resolve the problem.

I also printed these disks in colour but they are still black. The PS file i have for making the disks orgininally printed black. I changed it to print colour but all levels are 0 so it prints black but with the CMY colours. This makes for a much denser print.

On top of that, a simple 2ms pause at the top of the ISR before reading the port gave it sufficient time to settle in either an on or off position.

Problem solved! Thanks to all that helped me out.

Andrew