>*>It is possible to print suitable bands on a piece of paper using a laser
>*>printer, if your requirement is not too exact.
>
>What is 'not too exact'. Remember those hygrometers using a paper band
>glued on a brass spiral ?

Well I was thinking in terms of positional resolution :)

The one I saw done here for a project used about 25 thou line/25 thou space,
giving 20 lines per inch. It should be possible to do finer lines than this
if the opto has a suitable slit for viewing it.

The other problem may be absolute position change as the paper
expands/shrinks with humidity changes. If the lines could be printed on
Mylar film this would be a lot better in this respect. However as a real
quick get something up and running, paper should do just fine.

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