Some Prospects in the Field of Electronics* 



By V. K. ZwoRYKiN 



Radio Corporation of America 



[With 4 plates] 



The boundaries of the field of electronics, like those of almost any 

 branch of technology, are vague. Enclosing within them everything 

 in which the electron plays a vital function would certainly take in too 

 much territory, yet restricting the domain of electronics to devices 

 involving the employment of free electrons only would leave out such 

 items as crystal triodes and diodes which, by reason of their function, 

 have been quite generally claimed by workers in electronics. 



It must be recognized, however, that until recently the free electron 

 has been responsible for the role which electronics has come to play in 

 the modern world. Its extraordinarily large specific charge makes it 

 possible to impart to it high velocities with the aid of modern electric 

 fields and to deflect its path with ease by either electric or magnetic 

 forces. This is the reason for its effective use for the amplification 

 of rapidly varying currents or voltages and tlie generation of high- 

 frequency oscillations in the vacuum tube, for the indication of voltage 

 and current variations in the oscillograph, and for the generation of 

 picture signals in the television camera and the reconstruction of the 

 televised scene in the viewing tube. The same propert}' proves val- 

 uable in the detection and measurement of light by phototubes and in 

 the generation of X-rays in X-ray tubes. Finally, in the electron 

 microscope the scattering properties of matter for fast electrons, 

 the nature of their interaction with magnetic and electric fields, and 

 their wave characteristics combine to permit the use of free electrons 

 to extend the recognition of microscopic detail by two orders of 

 magnitude. 



The history of electronics can conveniently be divided into four 

 overlapping periods. In the first, ushered in by DeForest's invention 

 of the audion and terminated, approximately, by the First World War, 

 electron currents were controlled in vacuum tubes in much the same 

 manner as a steam valve controls the flow of steam in a pipe. No more 



1 Reprinted by permission from the Journal of the Franklin Institute, vol. 251, No. 1. 

 January 1951. 



235 



