PURPOSE: Show application of anamorphic lenses to wide-screen movies.
DESCRIPTION: A frame of a wide-screen movie is projected through a normal lens (far right above) and an anamorphic lens (center) which magnifies the horizontal axis more than the vertical axis. The anamorphic lens is constructed using two cylin drical lenses with different focal lengths. In this demonstration the beam is split after passing through the film. One half of the beam is focused onto the screen by the spherical lens; the other half is focused by the combination of a 20cm cylindrical lens focusing horizontally and a 30cm focal length cylindrical lens focusing verticlally.
Projectionists apparently call this a " 'scope lens." Such a lens is available (see picture at left above) for individual viewing.
REFERENCES: (PIRA unavailable.)
EQUIPMENT: Bright point source with condenser lens and iris, half-silvered mirror, plane mirror, 30 cm focal length spherical lens, 20 cm focal length cylindrical lens, iris, 30 cm focal length cylindrical lens, frame of wide-screen film, real a namorphic lens.
SETUP TIME: 10 min.
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