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

I think this thread may have instantly wandered off topic. When the original
poster mentioned "optical" mice, I took it to mean the new ones with *no* moving
parts, no ball, no wheels, no encoder etc.

I assume that they contain somethink akin to a mini-camera whose output goes
through some motion detection.

I don't know what their resolution is, but it seems finer than for mechanical
mice.

My only concern is that, at least for the one I have (a Logitech), after a
couple of seconds of inactivity, the LED which illuminates the mousing surface
dims (to save power), and it brightens up again when the mouse is moved. I
suspect that the mouse is less sensitive when the light is dimmed, so if you
were trying to use it as an absolute motion detector, you would get lost motion.

They did not, however, strike me as being very expensive...
-Kevin Martin