Electronic focal plane shutter
AssigneeRecon/Optical, Inc.
InventorsJohn G. Hughes, Thomas R. Hodek, Wayne Hamlin
Life of this patent
Estimating the term…
Abstract
A photographic shutter includes first and second curtains having opaque portions terminating at first and second edges which are positionable in spaced relation to define an exposure slit. Rollers support the curtains for movement of the slit in a certain path and through an exposure region. Electrical servo motors drive the curtains to control the width of the slit and to move the slit through the exposure region. A digital control circuit develops a command signal for control of movement of the slit through the exposure region. A drive circuit controls the servo motors in accordance with the command signal to obtain a certain velocity of movement of said slit at each position of said slit in said exposure region.
Claims11
A photographic shutter, comprising:
- first and second curtains having opaque portions terminating at first and second edges which are positionable in spaced relation to define an exposure slit, support means supporting said curtains for movement of said slit in a certain path and through an exposure region, drive means including electrical servo motor means for driving said curtains to control the width of said slit and to move said slit through said exposure region, control circuit means for developing a command signal for control of movement of said slit through said exposure region, and drive circuit means for control of said servo motor means in accordance with said command signal to obtain a certain velocity of movement of said slit at each position of said slit in said exposure region.
A photographic shutter, comprising:
- first and second curtains having opaque portions terminating at first and second edges which are positionable in spaced relation to define an exposure slit, support means supporting said curtains for movement of said slit in a certain path and through an exposure region, and drive means including electrical servo motor means for driving said curtains to control the width of said slit and to move said slit through said exposure region, said support means including first and second rotatable elements having peripheral portions coupled to said first and second curtains for effecting movement of said curtains in said path in proportion to the angle of rotation of said rotatable elements, and said electrical servo motor means including shaft means drivingly coupled to said rotatable elements.
Dependencies are inferred from the claim text.