Abstract: A projector having a rolling loop film transport mechanism is provided with a film decelerating cam unit that is located in advance of the aperture of the projector. Deceleration pins carried by a pair of vertically spaced arms that project from the cam unit engage in upper and lower marginal perforations in the film and travel with the film towards the aperture and decelerate the film as each frame is advanced. The cam unit includes two cams, one of which causes the decelerating motion of the pins, and a return motion in the reverse direction, while the other cam causes the pins to advance and retract into and from the film path respectively. By positively retracting the pins, their return movement against the direction of film travel can take place independent of the motion of the film. As compared with the prior art, acceleration forces and resultant stresses on the cam are reduced and the cam unit can operate at higher frame rates and/or with smaller rotor gaps.

Abstract: An alternate eye 3-d projection system has a projector projecting alternate eye left and right images, has alternating eye 3-d glasses alternating between left and right lens transmissiveness, and has a phase delay unit synchronizing the left lens transmissiveness to left images and right lens transmissiveness to right images. A timing shutter is driven through a mechanical link to the projector primary mechanism at a frequency proportional to the frequency of the transition between images. A sensor outputs pulses according to the rotationally frequency of the timing shutter. The phase delay unit receives the pulses, a multiplier multiplies the frequency of the pulses, a phase lock loop locks on to the frequency and a counter counts the pulses. After a preset delay the counter outputs a pulse. The delay is adjustable. The counter pulse enables a 60 KHz oscillator. The oscillations are counted by another counter and passed to a transmitter.

Abstract: Projected image misalignment in a 3-D motion picture projector is corrected by shifting one of the projection lenses in accordance with a predetermined program during presentation of the motion picture. In one embodiment, manually initiated control signals for adjusting the lens shift are recorded in a memory and can be subsequently retrieved for automatically controlling lens shift. In another embodiment, lens shift is controlled by reading predetermined witness marks on the film.

Abstract: A camera for producing 3-D motion pictures has "left eye" and "right eye" camera lenses and two corresponding film transport mechanisms. Images to be recorded on films transported by the mechanisms are reflected by semitransparent mirrors and the mechanisms and the mechanisms are arranged so that the mirrors turn the images transversely of the films. Contact prints made from the films can then simply be turned face-for-face to correct for the image reversals due to the presence of the mirrors. The contact prints are then correctly oriented for projection.

Abstract: In an alternate eye 3-D motion picture projection apparatus of the rolling loop type, light projection is accomplished by the combination of focal plane shutters that are coupled to the rotor of the projector and a supplementary shutter arrranged to trim the projected light so that discrete "left eye" and "right eye" images are projected. Various embodiments are disclosed in which a rotary blade shutter is located at the stop of the projection lens. Where there are two projection lenses, a single blade or two counter-rotating blades trim the light projected through both lenses.

Abstract: A 3-D motion picture projector comprises two rolling loop film transport mechanisms arranged in vertically superposed relationship with the pricipal components of the two mechanisms in vertical alignment with one another. Each film transport mechanism includes a cam unit for decelerating the film as it approaches the aperture for projection. The two cam units are driven from a common vertical drive shaft by toothed belt drives. The lower cam unit is mounted on an arm so that it can be swung out to an inoperative position for maintenance and service. The belt drives maintain the drive coupling at this time and automatically restore proper cam timing when the cam unit is returned to its operative position.

Abstract: A method of producing and displaying a 3-D motion picture is disclosed. Two master film negatives are prepared using a camera rig employing one camera that looks directly at the subject through a semi-transparent mirror and a second camera that looks at the same subject by way of the reflective surface of the mirror, to obtain left and right eye images. The cameras are oriented so that the mirror images recorded by the second camera are turned laterally of the film in being reflected by the mirror. Contact prints are made from the negatives. Before projecting the images, the contact print from the negative that was shot by way of the mirror is turned about its longitudinal axis so that images on that print are turned laterally. Images from the two prints are simultaneously projected onto the same screen to produce a coincident 3-D image. The left and right eye images are optically coded, for example by using optical filters that are polarized at right angles to one another.

Abstract: A film transport mechanism for an optical printer in which the film is positively clamped and laterally tensioned at the position of the aperture between each film advance step, so that the film lies absolutely flat in the focal plane of the lens system of the printer during exposure. This is achieved by providing registration pins and a pressure pad at one side of the film and a curved blade at the other side that move towards and clamp the film. The blade progressively tensions the film laterally against the pressure pad and registration pins.

Abstract: A transport and register movement for motion picture cameras and projectors and having spaced transport arms with cam operated claw pins and a crank shaft and transmission between the arms to oscillate the same and with a laterally offset drive shaft and cam operated register pins and a crank pin oscillating a counterbalance in opposition to motion of the arms.

Abstract: A film support element assembly is disclosed, primarily for supporting film in relation to a projection aperture in a motion picture projector having a rolling loop film transport mechanism. In a preferred embodiment the film support element is a so-called "field flattener" and has a cylindrically curved surface over which successive frames in the film are laid by the mechanism. Cleaning means are provided adjacent the film path and the lens element can be displaced to bring a fresh portion of the surface into the film path. At the same time, the cleaning means remove debris from the surface. In one embodiment the lens element is vibrated to discourage adhesion of debris.

Abstract: A projection screen assembly is disclosed. The assembly includes a screen which can be lifted into an extended position or lowered into a collapsed configuration for permitting a building in which the screen is installed to be used for other purposes. Lifting means is provided for raising the screen and tensioning it in the vertical direction. Lateral tensioning is effected simultaneously by tensioning elements disposed one adjacent each side edge of the screen. The tensioning elements are coupled to the screen by lateral tensioning members which are of progressively decreasing length in directions extending inwardly from the upper and lower margins of the screen so that the tensioning elements adopt the shape of caternary curves. When the screen is tensioned vertically, these curves are flattened so that the screen is tensioned laterally by the lateral tensioning members.

Abstract: A film support element assembly is disclosed, primarily for supporting film in relation to a projection aperture in a motion picture projector having a rolling loop film transport mechanism. In a preferred embodiment the film support element is a so-called "field flattener" and has a cylindrically curved surface over which successive frames in the film are laid by the mechanism. Wiper elements are provided above and below the film path and the lens element can be displaced to bring a fresh portion of the surface into the film path. At the same time, the wiper elements remove debris from the surface. The wiper elements are removable for disposal of collected debris.