An optical control device includes a drive member formed with a plurality of reflecting regions along a second track and movable along the second track for driving a driven member to move along a first track. The MEMS component is configured to convert. An emergency cutoff device is provided so that the valve disc closes the hole in an emergency when electric power supply is cut off. The distance to the nearest calcified region is then determined for each location not corresponding to a calcified region, and the additional stress caused by the calcified regions is then determined from values stored in a memory. A reader may store at least a tag identifier.