Re: [CAD_CAM_EDM_DRO] Hacking Optical Mice as position/distance encoders

----- Original Message -----
From: "Tim Goldstein" <timg@...>


> If you open up standard a mouse you will find 2 low line count quadrature
you would get 1440 counts
> per inch in quadrature which works out to just

Tim,

Where do you get the quadrature from, all the mice I have ever opened up
only have a single optical sensor for each axis so that, with the figures
you give, the resolution would only be 360 counts / inch. Also, many of the
cheaper mice have less than the 36 slots you mention and, since the encoder
disks are usually just a plastic moulding, you will often find bits of fash
and distortion on the 'blades'. Of course, the reason they are so cheap
nowadays is that they are not really made for any kind of true accuracy -
its not necessary as the computer in our heads, via hand/eye feedback, gives
the accurate control necessary.

Ian
--
Ian W. Wright
Sheffield UK
www.iw63.freeserve.co.uk