Patent GB-411819-A (GB)
Title: Improvements in or relating to apparatus for reproducing on incandescent lamp screens pictures derived from cinema films
IPC: G09F13/28
Filed: 1932-12-07
Abstract: 411,819. Television. ROSENBERG, H., 7, Parkstrasse, Dahlem, Berlin. Dec. 7, 1932, No. 34748. Convention date, Dec. 8, 1931. [Class 40 (iii).] In an arrangement for reproducing film pictures on a screen of incandescent lamps controlled by relays which are operated by associated light-sensitive cells illuminated through the film band, each relay is provided with two or more windings, one of which is included in the circuit of the cell, whilst another operates in conjunction with the first mentioned winding for maintaining the associated lamp illuminated. An interrupter operating in timed dependence on the film projector interrupts the lamp circuit and releases the associated relay for operation in accordance with the corresponding portion of the succeeding picture. The relay 9 when operated by the cell 1 closes at contacts 6, 7 the circuit of the holding winding 91 and of the lamp 2, and an interrupter 4, which opens the lamp circuit after the film has been moved to expose the succeeding frame to the light-sensitive cells, is arranged to close the lamp circuit a short time after the cells have been exposed to that picture frame. For cells which pass considerable current when not exposed to light, an opposing winding is provided for the relay. In the arrangement shown in Fig. 3, when the cell 1 is not exposed to light, the current flowing in the circuit including the resistance 12 and the contact 14, engaged by the armature 7 when the relay 5 is not operated, balances the current normally flowing in the winding 10 of the cell circuit. When the cell is illuminated the armature 7 of the relay moves to the contact 6, opening the circuit of the winding 11 and the winding 10 maintains the relay in its operated condition. A contact 13 in the circuit of the winding 10 is opened by an interrupter after each change of picture. As shown in Fig. 4 an interrupter 24 is arranged to interrupt the circuit of all the lamps 2 shortly before the film is moved, and to close the circuit of the lamps and of the holding windings 9<1> shortly after the cells have been exposed to the succeeding picture frame so that no current passes over the contacts 6, 7 when they are being opened or closed. The Specification as open to inspection under Sect. 91 includes an arrangement, Figs. 8, 9, 10 (cancelled and not shown) in which each lightsensitive cell controls a vertical row of lamps of the screen through a rotating switch member. This subject-matter, which has been described and claimed in Specification 408,128, does not appear in the Specification as accepted. The Specification as open to inspection under Sect. 91 also includes arrangements for the mounting of a number of light-sensitive cells in a common supporting member. As shown in Fig. 12 (Cancelled), the cells are mounted on a conducting plate 30 which forms one electrode for all the cells, the second electrode for each individual cell being formed by a metal bolt 31 separated from the plate 30 by an insulating sleeve 32. In an alternative arrangement, Fig. 13 (Cancelled) the cells are mounted in recesses of a non-conducting plate 32, one electrode being constituted by a conducting member 30 common to all the cells, and the second electrodes for the cells being metallic studs 31 seated in the bottom of the recesses of the non-conducting plate. In a further arrangement, Fig. 14 (Cancelled and not shown), a metallic lattice mounted on a non- conducting plate forms one electrode for all the cells, the second electrode being constituted by a metal stud in contact with one surface of the cell and passing through the non-conducting plate. This subject-matter does not appear in the Specification as accepted. The Specification as open to inspection under Sect. 91 also includes arrangements, Figs. 4, 5, 6 (Cancelled and not shown) in which the coils of the relay and the light-sensitive cell are included in the arms of a Wheatstone bridge This subject-matter, which does not admit of satisfactory abridgment, is not included in the Specification as accepted.