(under subclass 1) Subject matter in which a light responsive means regulates the abrading operation.
(1) Note. Included herein is a device in which a beam of light is reflected from the workpiece or an index mark thereon to the light sensitive means; a micrometer operably connected to a light source; or a device in which a tool or a workpiece covers or uncovers the light sensitive means for sensing a condition of the tool or the workpiece.
