Spindt cold cathode for displays

Charles “Capp” Spindt with the Spindt cold cathode, circa 1970s.

SRI’s efficient cathode, created in 1973, produced much higher current densities than traditional cathode ray tubes and led to today’s “instant-on” field emission displays (FEDs) for flat-panel computers and televisions. The technology is named for Charles A. “Capp” Spindt, the cathode’s inventor.

With this improved method for making small cathodes, SRI addressed other applications as well. An early application was an electron source for a storage tube that would hold an image as long as desired. The field-emission array was capable of delivering high brightness to such a display.

Because of their power efficiencies, the use of field-emission cathodes in microwave tubes would be ideal for satellite and space applications. NASA sponsored SRI’s work in this area for about 13 years.

Read our 75th anniversary blog feature

75 years of innovation: Spindt cathode field emission technology

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