US Patent 9980639 Visual compensation system and optometric binocular device

A visual compensation system (10) enabling observation, with variable optical power correction, along an optical observation axis (X) includes:—a first rotatable optical element (2) centered on the optical axis (X) and having a first cylinder power along the optical axis (X); —a second rotatable optical element (4) centered on the optical axis (X) and having a second cylinder power along the optical axis (X); and—a lens (6) having the optical axis (X) as the axis thereof, and moreover having variable sphere power.