Eastman-Kodak Company

William Thomas Hochreiter

Fredric Alton Mindler

Hans-Peter Baumeister

William K Hickok

Matthew DiPietro

Lawrence J Bernstein

Guilford Edwin Kindig

Loren Jackson Craig

A skip-field guard-bandless video tape recorder records and plays back adjacent tracks on a video tape with two closely adjacent heads of opposing head gap azimuth angles (to suppress cross-talk), only during alternate (odd) half-rotations of the head drum. Unavoidable cross-talk of synchronization pulses from adjacent tracks does not create visible interference or timing errors during playback by virtue of a special offset angle .theta..sub.1, between the adjacent recording heads, proportional to the linear offset distance between adjacent tracks. During playback, skipped fields are 'filled-in' by a repetition of each recorded field through a second (duplicate) pair of closely adjacent heads of opposing azimuth positioned to retrace the recorded tracks during the other alternate (even) half-rotations of the head drum. An offset angle .theta..sub.2 between the two head pairs (i.e., between opposing heads of like azimuth) corresponds to a half horizontal video line and provides for precise self-interlacing of the repeated fields.

Zero guard-band skip-field video cassette recorder

A camera having an adjustable mechanism to set an exposure aperture, a shutter to control the duration of an exposure and a member movable in a first range to initiate adjustment of the mechanism and movable in a second range to actuate the shutter to open the exposure aperture, includes a single electromagnet effective to become energized and subsequently de-energized to control the mechanism to set a desired exposure aperture and effective to be energized during an open condition of the shutter to hold the shutter open until de-energization thereof. The electromagnet is connected in a control circuit that has a photosensor exposed to scene brightness and switches controlled by the movable member to operatively connect the photosensor to the electromagnet. The circuit is effective upon actuation of the switches during movement of the member in the first range to energize or to energize and then quickly de-energize the electromagnet to establish the desired exposure aperture in accordance with scene brightness, and during movement of the member in the second range to re-energize the electromagnet and after an exposure of duration related to scene brightness to de-energize the electromagnet to initiate shutter closure.

Exposure control mechanism

A camera having a self cocking shutter with a shutter actuating member for initiating exposures and a piezo-electric flash device with a flash firing spring that is cocked in concert with film advance, includes a double exposure prevention latch that disables the shutter actuating member when the flash firing spring is not cocked.

Double exposure prevention device

A camera adapted to make exposures of a scene illuminated by substantially constant or transient (flash) light includes exposure control apparatus having a photosensor to effect an exposure of duration related to the intensity of the light, a focus control and first and second light attenuating elements mounted to be selectively positioned in and out of the optical path of the photosensor. The attenuating elements are biased to move toward the optical path; and for exposures in substantially constant light, the first attenuating element is held out of the optical path. For exposures in flash light, the first attenuating element is positioned within the optical path while the second attenuating element is moved out of the optical path while the second attenuating element is released to move into the optical path to an extent determined by the focus control.

Growing community of inventors

Rochester, NY, United States of America

William Thomas Hochreiter