A METHOD AND SENSOR ARRANGEMENT FOR DETECTING A MOVEMENT OF A TIMEPIECE SETTING STEM AND A TIMEPIECE COMPRISING THE SENSOR ARRANGEMENT

摘要

The invention relates to a method of detecting movement of a time piece setting stem (1) arranged to be axially moved along a longitudinal axis and / or rotated about its longitudinal axis. The method comprises the steps of: (a) illuminating a part of the setting stem 1 by the light source 5; (b) the photodetector (12) receiving the reflected or diffracted light pattern (9) from the setting stem (1); (c) forming a first pixel pattern representing a light pattern reflected by the processor (13) at a first time instant; (d) forming a second pixel pattern, wherein the processor (13) represents a light pattern reflected at a later second time instant; And (e) determining that the setting stem (1) has been moved if the second pixel pattern is different or shifted relative to the first pixel pattern.