Abstract: The invention relates to a masking device (1), for a cinema screen, comprising at least two masks arranged in front of said screen (2) and arranged in pairs, symmetrically along at least two sides thereof, left and right, and/or top and bottom, each mask comprising a rolling axle (7) and a cloth (8) rolled around said axle. Each cloth has a rolled edge (10) and a free edge (9), characterised in that at least the lower mask (6) and/or the pair of left (18) and right (19) masks have a tensioner (12), for holding the free end of the cloth thereof, the length of the tensioner being greater than the length of the cloth and means for controlling the position of the tensioner in a plane essentially parallel to the plane of the screen (2) and in a direction perpendicular to the direction of unrolling of the cloth such that each cloth (8) can be unrolled from the axle (7) thereof in the direction of the centre of the screen (2) to adjust the masking surface of said mask.

Abstract: The invention relates to a masking device (1), for a cinema screen, comprising at least two masks arranged in front of said screen (2) and arranged in pairs, symmetrically along at least two sides thereof, left and right, and/or top and bottom, each mask comprising a rolling axle (7) and a cloth (8) rolled around said axle. Each cloth has a rolled edge (10) and a free edge (9), characterised in that at least the lower mask (6) and/or the pair of left (18) and right (19) masks have a tensioner (12), for holding the free end of the cloth thereof, the length of the tensioner being greater than the length of the cloth and means for controlling the position of the tensioner in a plane essentially parallel to the plane of the screen (2) and in a direction perpendicular to the direction of unrolling of the cloth such that each cloth (8) can be unrolled from the axle (7) thereof in the direction of the centre of the screen (2) to adjust the masking surface of said mask.