WIDE-BANDWIDTH INTENSITY MODULATION OF A CATHODE-RAY BEAM WITH DC TO 12-GHZ GUN.
STANFORD UNIV CALIF STANFORD ELECTRONICS LABS
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A new electron-gun structure capable of cathode-ray beam modulation with frequencies from dc to 12 GHz has been developed. The modulating structure consists of a coaxial transmission line with an integral cathode and modulating grid forming part of the center and outer conductors, respectively. The gun can be used with conventional magnetic and electrostatic focusing and deflection systems. The design requirements for the coaxial structure are compatible with those for high resolution. An experimental cathode-ray tube, built with a gun of this design and using a total accelerating potential of 24 kV, produces a visible display of a single pulse of nanosecond duration and an amplitude as low as 1 V at a writing speed of 2 X 10 to the 7th power cmsec this display can also be photographed. The dynamic range of beam intensification, corresponding to an increase in spot size from a minimum of 0.004 in. to 0.008 in., is approximately 20 dB for single-shot pulses of nanosecond duration. For repetitive pulses the dynamic range is greater, typically 30 dB. This report describes the design and performance of two cathode-ray tubes with guns of the above construction and also describes the design and operation of the SH1968-B Nanosecond Beam Intensification Display Unit. The SH1968-B is a self-contained display device consisting of the two display tubes and all associated sweep circuits and power supplies. Author
- Electrooptical and Optoelectronic Devices