Image-stabilized binoculars
Image stabilized binoculars are binoculars that have a mechanism for decreasing the apparent motion of the view due to binocular movement.
Several different mechanisms have been used for image stabilization.
Active systems
In these systems the change in attitude of the binoculars is sensed electronically, and some part of the system is changed to correct this offset. A lens group may be shifted, or the angle of a fluid filled prism may be changed.
Passive systems
In these systems there is no feedback from a sensor to the corrective element. The whole binocular may be stabilized by use of a gyroscope, or the binocular prisms may be disenganged from the housings, allowing them to be unaffected by binocular movement.
Use
Image stabilized binoculars are frequently used when viewing from a moving object such as a boat or plane. They are also very helpful with high powered binoculars. Canon image stabilized binoculars have become popular with amateur astronomers.
Other image stabilized optics
Image stabilization is also used in video and camera lenses.