Flat cathode ray tube having magnetically collimated electron beam device

摘要

An evacuated envelope has front and rear walls spaced apart by a plurality of side walls. On the inner surface of the front wall is a cathodoluminescent screen. A magnet structure extends along one of the side walls spaced therefrom and has two spaced poles each of which is parallel to the front wall. The magnet structure generates a uniform magnetic field between the two poles. An electron gun is within the envelope for generating and directing an electron beam into the space between one side wall and the magnet structure. Also included in the device is means for deflecting the electron beam so that it will pass between the poles of the magnet at a plurality of points along the magnet's length. The deflection means maintains a constant angle of incidence at which the electron beam enters the space between the two poles at various points. Means are also included for deflecting the electron beam towards the screen as it emerges from between the magnet poles.