An apparatus is disclosed. In some examples, the apparatus comprises a mechanical input mechanism comprising a rotatable shaft. In some examples, the apparatus comprises an optical sensor configured to detect a rotation of the shaft and detect a movement of the shaft toward or away from the optical sensor. In some examples, the apparatus comprises an optical sensor configured to detect light incident on the optical sensor, the light having a position and an orientation, the orientation of the light based on at least a position of the rotatable shaft, detect a rotation of the shaft, and detect a movement of the shaft based on at least a change in the orientation of the light. In some examples, the apparatus comprises a housing. In some examples, a mechanical input mechanism comprising a rotatable shaft is coupled to the housing and configured to contact a force sensor coupled to the housing in response to a user input. In some examples, the force sensor is configured to detect a position of the shaft and detect an amount of force between the shaft and the force sensor that is based on the user input.