초록 ▼

A variable beamwidth stage light relying upon an axially movable reflector for changes in beamwidth. The reflector has a plurality of radially outwardly and axially forwardly extending leaves in side-by-side relation to define a bowl-shaped reflector surface. A stationary support flange is in fricti

A variable beamwidth stage light relying upon an axially movable reflector for changes in beamwidth. The reflector has a plurality of radially outwardly and axially forwardly extending leaves in side-by-side relation to define a bowl-shaped reflector surface. A stationary support flange is in frictional contact with the radially outward surface of each leaf. The reflector leaves are sandwiched between a base member and a ring member at the base of the reflector. A motor driven lead screw is attached to the base member to cause axial movement of the reflector relative to the support flange. The reflector defines a first and a second focal point along the axis of the reflector. A light source is fixed at the first focal point, which remains substantially fixed relative to the base member. Contact of the support flange with the reflector leaves causes the diameter of the reflector leaves to vary as the base member is moved, thereby causing displacement of the second focal point and variation of the bandwidth issuing from the reflector.

대표청구항 ▼

A variable beamwidth light comprising, a bowl-shaped reflector including a plurality of elongated leaves made of an elastically deformable material and having inward portions disposed adjacently to form a base which defines a central aperture and from which said leaves radiate outwardly and forwardl

A variable beamwidth light comprising, a bowl-shaped reflector including a plurality of elongated leaves made of an elastically deformable material and having inward portions disposed adjacently to form a base which defines a central aperture and from which said leaves radiate outwardly and forwardly along the center axis of said aperture to respective outward ends collectively defining a peripheral edge of said reflector, said leaves being bent at multiple predetermined incremental positions and forming substantially the entirety of the reflector, a light source fixed relative to said base and axially aligned with said central aperture, a fixed flange defining a shaping aperture having a diameter less than twice the length of said leaves through which said reflector is movably disposed said leaves extending through said shaping aperture and being constrained to assume an elliptical shape by engagement with said flange, and means for displacing, relative to said fixed flange, said reflector and said light source along said axis to cause said reflector to be elastically deformed at said incremental positions to curve through shapes belonging to a selected common family of ellipses as said reflector is moved axially relative to said flange means, to selectively vary the ellipticity of said reflector and thus vary the width of a light beam reflected from the reflector.