An electron beam head for reproducing magnetically recorded video signals wherein magnetic fields from the record medium are channeled to the interior of the envelope to deflect the primary electrons transversely to the scanning direction of the beam. In one embodiment, the sensing electrodes are... Show moreAn electron beam head for reproducing magnetically recorded video signals wherein magnetic fields from the record medium are channeled to the interior of the envelope to deflect the primary electrons transversely to the scanning direction of the beam. In one embodiment, the sensing electrodes are at opposite sides of the magnetic field region at an end wall of the envelope, while in another embodiment the primary electron beam passes through the openings in a grid of magnetic wires so as to interact with the magnetic fields therebetween, electrostatic deflecting means serving to deflect the electron beam through a substantial angle as it leaves the grid so as to impinge on sensing electrodes remote from the grid. In a third embodiment, secondary electrons are conducted into a branch tube extending from the main envelope and a single electrode senses the degree of deflection of the secondary electrons by the magnetic fields permeating the secondary emission region.
Sponsorship: IIT Research Institute
United States Patent Show less