Eyewear including a support structure defining a region for receiving a head of a user. The support structure supports optical elements, electronic components, and a use detector. The use detector is coupled to the electronic components and is positioned to identify when the head of the user is within the region defined by the support structure. The electronic components monitor the use detector and transition from a first mode of operation to a second mode of operation when the use detector senses the head of the user in the region.