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

Feb., 1932] PATENT ABSTRACTS 261 drums and through the negative film adjacent to the outside drum to the positive film adjacent to the inner drum. The light source, when a reduction in film size is to be made, is positioned exteriorly of the large wheels over which the negative film is fed, and the light therefrom, passing through the negative film, falls upon the surface of the unexposed film carried over the smaller wheels. If the device is to be used for enlarging, the negative film is fed across the small wheels and the positive film across the large wheels, the light source being so re-positioned that the negative film passes between it and the positive film. 1,826,970. Television and Telephoto Device. J. L. WALKER. Oct. 13, 1931. Picture reproducing system in which two separate scanning systems are directed upon opposite sides of a reproducing screen. A photographic plate or viewing screen uses light from two separate light sources and projects light from one light source upon one side and from the other light source upon the other side of said photographic plate or viewing screen and the illumination from the two separate light sources combined at one point. The recording lamps of the two scanning systems are connected in parallel in the output circuit of the receiving apparatus, and each so positioned on opposite sides of the screen as normally to give equal illumination upon the screen. 1,827,010. Film Flame Stop. L. D. KOHLMEYER. Oct. 13, 1931. The film is protected by a fire-proof frame structure forming compartments surrounding the film reels. The entrances to each of the compartments are provided with passageways formed between a pair of rollers carried on fixed axes in the passageway. A second pair of rollers is mounted adjacent to each passageway for guiding the film through the passageway and at the same time forming a fire stop in the event of ignition of the film. 1,827,018. Photoelectric Cell. A. JOFFE. Assigned to Industrial Research Co. Oct. 13, 1931. A photoelectric cell comprising a sheet-like insulating layer having a thickness not greater than 0.01 mm. having a photoelectrically active substance distributed through the insulating layer and a pair of electrodes supporting the layer, at least one of the electrodes being transparent to light. The invention is based on the discovery that when an ion is initiated or excited within certain substances of requisite thickness, notably dielectrics or other materials of low specific conductivity, and further, when the substance is subjected to considerable electrical stress, the medium through which the ion travels at high velocity gives rise to an augmentation of the number of charged particles. The accumulative action effects a general movement of ions toward one of the electrodes and results in a greatly magnified space current with abrupt reduction of impedance to produce amplification of the impulse originally exciting the single ion. The original impulse may be energy derived from any physical phenomenon such as light, heat, electron bombardment, or other electrical effects. 1,827,206. Film Support for Photographic Apparatus. F. H. OWENS. Assigned to Owens Development Corp. Oct. 13, 1931. A support for traveling films, comprising a pair of axially aligned movable members, one of said members being adapted to engage a film and cause the same to travel over the other member. A stationary member is disposed between said movable members and spaced therefrom to permit the passage of light to said film between said stationary and movable members and on each side of said stationary member. 1,827,282. System of Composite Photography for Motion Pictures. O.