Electronic devices with movable optical assemblies

Abstract

A head-mounted device may include optical assemblies for presenting images to a user. Motors may be used to adjust the spacing between the optical assemblies to accommodate different interpupillary distances. The force with which the motors move the optical assemblies towards a central nose bride portion of the device may be limited. The force may be limited using a clutch such as a magnetic clutch or a physical clutch based on structures that decouple from each other to limit the force. The force may also be limited by monitoring the force and halting the motors in response to detection of a given amount of force. Sensor measurements and electrical motor load measurement may be used in measuring the force. If desired, motor operation may be controlled by a user-operated button.