Substrate treatment device and method and encoder scale treated by this method

摘要

The invention provides a substrate treatment method and apparatus to produce a pattern on the substrate (10). Embodiments show a substrate (10) in the form of a rotary encoder ring (10) having a pattern of marks producable by means of a laser treatment device (122) controllable by a controller (100, 110) to produce the pattern in the correct manner whilst there is continuous relative displacement between the ring (10) and the laser treatment device (122).