Patent
1977-09-30
1979-07-10
Gellner, Michael L.
G03B 708
Patent
active
041605870
ABSTRACT:
A camera with a focusable objective has two secondary projection systems, at least one of which is continuously adjustable, working into a photoelectric comparator which emits a coincidence signal whenever the two projection systems are trained upon the same object along the optical axis of the main objective. A position sensor, coacting with a swingable mirror in the adjustable projection system, generates a correlation signal whenever the mirror position matches the setting of the main objective as determined by the axial position of a shiftable lens member thereof. With the swingable mirror set in oscillations to scan the object space in front of the main objective, the two signals are generated in the form of short pulses during each scanning sweep and are fed to a phase detector whose output may control a drive motor for the shiftable lens member to bring the main objective into correct focus. The position sensor may include a source of an ancillary light beam, not necessarily within the visible spectrum, and a photoelectric detector therefor; the elements determining the orientation of that light beam (source, detector and/or reflecting surfaces) are then located at least in part on the swingable mirror and on a carrier for the focusing lens member. If the secondary projection systems include a pair of stationary reflectors in a region of the objective in which the light rays from an object on its axis are parallel to that axis when the objective is focused thereon, the swingable mirror can be replaced by a stationary one while the comparator acts as the position sensor.
REFERENCES:
patent: 3435774 (1969-04-01), Stimson
patent: 3838275 (1974-09-01), Stauffer
patent: 3958117 (1976-05-01), Stauffer
patent: 4002899 (1977-01-01), Stauffer
patent: 4021821 (1977-05-01), Peterson
Heiniger Wilfred
Kreienbuehl Claude
Millan Manuel
Bolex International S.A.
Gellner Michael L.
LandOfFree
Camera equipped with range finder for manual or automatic focusi does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Camera equipped with range finder for manual or automatic focusi, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Camera equipped with range finder for manual or automatic focusi will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-737609