GB485904A - Improvements in and relating to cathode ray tubes - Google Patents

Abstract

485,904. Oscillographs. RADIOAKT.- GES. D. S. LOEWE. Aug. 21, 1936, No. 23059. Convention date, Aug. 23, 1935. [Class 37] [Also in Groups XL and XXXV] In an arrangement for producing an impulse at the passage of an alternating voltage through zero, the voltage is applied to the deflecting plates of a cathode-ray tube, the beam of which is focused by an electronoptical system and impinges in its undeflected position upon one electrode and in any deflected position upon a second electrode. The alternating potential is applied to a pair of deflecting plates 4, 4<1> of a cathode-ray tube 3, so that when the potential is zero the beam is undeflected and strikes an electrode 5 or passes through an apertured diaphragm and strikes a plate electrode or a wall coating behind the diaphragm. The impulses generated every time the potential passes through zero may be used for starting a relaxation oscillator for synchronizing and other purposes, particularly in connection with television systems. The Specification as open to inspection under Sect. 91 comprises also the use of the impulses produced each time the alternating voltage passes through zero to trigger off a discharge tube or a pentode and the device may be used for obtaining synchronization impulses in television transmitting or receiving arrangements. In a modification, the electron beam in its undeflected position passes through an apertured diaphragm and falls on a fluorescent screen at the end of the tube, the periodic fluorescence of which affects a photo-electric cell which generates impulses. This subjectmatter does not appear in the Specification as accepted. Reference has been directed by the Comptroller to Specifications 344.315, 366,053, and 379,812, [Group XL].