1. A user display apparatus, comprising: a head-mounted display unit including a see-through lens; an augmented reality emitter, associated with the head-mounted display unit, which emits light to a user's eye, the light represents augmented reality video images; at least one sensor which tracks an orientation and location of a head of the user; and at least one control circuit which controls the augmented reality emitter, responsive to the at least one sensor, to display the augmented reality video images in response to determining that the user is looking at a video display screen, where the augmented reality video images are synchronized with content displayed by the video display screen.