Patent ID: 8411214

Claim:
A system for selectively obscuring a user's vision, the system comprising: a head position detection element for detecting a position of the user's head; eyewear having variably transmittive lenses; and a controller configured to receive user head position information from the head position detection element comprising information regarding an up and down position of the user's head relative to a predetermined point in space in front of the user and further configured to control the transmittivity of the lenses based on the user head position information by varying an electrical signal applied to the lenses, wherein the controller is configured to reduce the transmittivity to darken the lenses and thereby obscure the user's vision when the user's up and down head position is above the predetermined point in space, and wherein the controller is configured to increase the transmittivity to lighten the lenses and thereby not obscure the user's vision when the user's up and down head position is below the predetermined point in space.