The RCA Selectron -- US Patent 2,558,461 Selectron Electron Optics

Jan A. Rajchman, Radio Corporation of America
Applied: 28 December, 1949
Granted: 26 June, 1951

Electron optics topology showing a labyrinth-type path so that emission from a linear array of 
square cathodes is concentrated and elecrtostatically deflected through the selection bars to the storage eyelets. The '461 patent relates to the electron optics of the 256-bit planar type tube. '461 describes the geometry of electron emission from the faces of square cathodes. The beams are then guided along a 45 degree path and then through the addressing bars before becoming orthogonal. One goal is to use the emission efficiently, not unlike beam forming techniques used in "beam-power pentode" electron tubes. Another goal is to minimize the "line-of-sight" between cathode and storage element. This is necessary because the heavy ions and particles of cathode coatings will travel to the storage elements and destroy their secondary-electron emissive properties.

US Patent 2,558,461 images (OCR'd) 644 kB
US Patent 2,558,461 images (OCR'd) 644 kB

US Patent 2,558,461 text (OCR'd) 84 kB
US Patent 2,558,461 text (OCR'd) 94 kB

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