Patent ID: 8922723

Claim:
An optical device comprising: at least one optical component configured to be electrically actuated such that a light transmission state is variable; a driver circuit for the at least one optical component; a power source unit for driving the at least one optical component; a pair of rims; a pair of temples having front and rear ends and connected at the front ends to their respective rims; and a pair of earpieces formed at the rear ends of their respective temples, the at least one optical component being supported by at least one of the rims, the power source unit including: a secondary battery; a power switch; a power switch control portion; and a use-status sensing portion for sensing the status of use by a user of the optical device, and the power switch control portion performing control to turn off the power switch when the use-status sensing portion does not sense any use by the user of the optical device, wherein, the temples are connected to their respective rims via hinges, including biasing means for biasing at least one of the temples such that an angular position of the at least one of the temples about the hinge coincides with a predetermined angular position corresponding to the device's status of not being in use, the use-status sensing portion includes a second sensing portion for sensing the angular position of the at least one of the temples to coincide with the predetermined angular position, and the power switch control portion turns off the power switch when the second sensing portion senses the angular position of the at least one of the temples to coincide with the predetermined angular position.