Hi Bojan,
just another idea,
If you ever wanted to give away the reflective method and use
the interrupted window method like I use then you still could make
a viable optical disc.
You could print your incremented pattern out on a disc as a negative
and etch away the holes where the counts are.
Put your photodetector pair either side of these windows and try that.
For mine, luckily, I had a purpose built one with 144 slots but I can't
see why a rogue like you couldn't build one.
I used a Gaugemaker program to make my index wheel printout.
This great little program does any increment gauge in any
circumference value from 0-360 degrees.
You can adjust the increment fonts, line width, length etc.
Here's the link:
http://forums.x-plane.org/index.php?...&showfile=6359
Pic 1 attached is a rough printout I used for my index wheel.
Pic 2 is the optical wheel type you would ultimately etch
if it ever worked. This pic is my Dec axis encoder with mouse guts
for photodetectors.
Steve