How well do US Digital encoders work in a dusty environment?
US Digital encoders are fairly robust to dusty environments. The encoders look
at multiple sets of window and bar pairs. Thus a speck of dust at any one window
will be averaged out by the other sets of windows and bars. Because of this
averaging effect, a number of windows can be covered completely and the module
will still not lose a count. The phased array differential modules that read the
disks have plenty of signal margin. An impressive demonstration of this is to
color the disk completely black with a Sharpie pen. The encoder will continue to
work without errors.