Journal of the Society of Motion Picture Engineers (1930-1949)

July, 1931] PATENT ABSTRACTS 143 The scanning mechanism is operated through a gear shift which controls t herate of movement of the scanner with respect to the picture. 1,803,278. High-Frequency Control of a Kerr Cell. T. W. CASE. Assigned to Case Research Laboratory, Inc. April 28, 1931. A sound modulating circuit is provided for operating upon a high-frequency oscillator and producing tlu-rt-from high-frequency current modulated in accordance with sound vibrations. The modulated energy is impressed upon a rectifying circuit and from the rectifying circuit the energy is supplied to a Kerr cell. The Kerr cell varies a beam of polarized light in accordance with the modulations impressed upon the carrk-r current for the production of a photographic record of light waves corresponding to sound waves. The variable light rays thus produced are directed upon a lightsensitive film for the recording of sound in accordance with the initial operation of the sound pick-up circuit. 1,803,313. Film Guide for Projectors. CARL BORNMANN. Assigned to Agfa Ansco Corporation. May 5, 1931. A film guide for projectors which consists of a metallic stamping having a rolled, horizontally extending upper edge and resilient fingers depending therefrom and adapted to engage the film adjacent its edges. The resilient fingers bear against the film and maintain the edges of the film flat against the film guide during the movement of the film past the exposure aperture. 1,803,346. Electromagnetically Operated Light Gate for Recording Sound F. H. OWENS. May 5, 1931. A sound record is recorded on a film by an electromagnetic gate which is operated in accordance with the actuation of a sound pick-up circuit for permitting variable light to reach the sensitive film strip. The light gate is operated electromagnetically and admits light through a system of lenses to the light-sensitive film. The parts of the light gate consist of overlapping plates which are shifted vertically with respect to each other for controlling the passage of light upon the film strip. 1.803.403. Sound-on-Film Attachment for Disk Type Phonographs. F. H. OWENS. May 5, 1931. An attachment for disk type phonographs in which a frame carrying a pair of reels with a film strip reel thereon is adapted to be mounted within a phonograph cabinet and the reels driven from the phonograph drive shaft. The frame carries a light source and a light-sensitive element between which the film having a sound record thereon is moved. The lightsensitive element operates a sound reproducing circuit in accordance with the sound record on the film. 1.803.404. Automatic Shutter Mechanism for Controlling Printing Light Intensity. F. H. OWENS. May 5, 1931. A shutter mechanism is employed in a film printing apparatus, which shutter is controlled in accordance with the intensity of the transmitted light of the printer. As the film is moved past the shutter opening, the size of the shutter opening is varied in accordance with varying light intensities selected for the film. The operating means consists of a continuous band having undulations or cam faces formed thereon. The shutter is mechanically connected to a member which is actuated by the movement of the cam faces on the continuous band to open or close the shutter. The movement of the film controls the operation of the moving band for controlling the effect thereof upon the shutter for determining the light intensity to which the film is subjected.