bf1104:
a box which will read the color of thread or wool or string
How detailed do you want the colour information to be?
Do you just want to distinguish red from blue? Or do you want to be able to identify different shades of red etc?
And if you want to identify different shades of a colour do you want absolute values (i.e, the same sample always gives the same result) or relative values - i.e. these two samples are the same and this third sample is different.
...R