240 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1951 



pattern for the future has in large part been established for broadcast 

 television, with the creation of a sound basis for the smooth change- 

 over or side-by-side existence of color and black-and-white television 

 (5). Nevertheless, a host of interesting engineering problems, whose 

 solution will lead to the simplification and improvement of different 

 phases of television equipment and television service, remain to be 

 solved and, to judge by the recent past, will be solved in original 

 fashion. 



There is another aspect of television development that has not 

 received, and probably will not receive, nearly as much attention as 

 broadcast television and that may yet, eventually, turn out to be of 

 even greater significance. This is industrial television — the utiliza- 

 tion of television techniques in industry, research, education, com- 

 merce — in short, in all fields apart from broadcasting. The basic 

 industrial television system, in the form of a self-contained, cable- 

 connected link incorporating a television camera and a combined view- 

 ing and control unit, enables the observer to transfer his vantage 

 point to dangerous and inaccessible locations ; to view simultaneously 

 several spatially widely separated scenes ; or to share an intimate view 

 with a large number of other observers without mutual interference. 

 The first condition is realized, for example, in the watching of care- 

 fully shielded radioactive reactions from a protected point, the check- 

 ing of engine performance by a camera mounted on the underside of 

 an automobile chassis, or the observation of the proper filling of the 

 scoops in strip mining by a camera placed directly above the scoop ; 

 the second, by the simultaneous observation of indicating instruments 

 at a number of substations from a central station; and the third, in 

 the watching of surgical operations on television receivers linked to 

 a camera mounted above the operating table or the presentation of 

 microslides at high magnification to groups of students; in the last 

 instance the microscope image is projected directly on the target of the 

 pick-up tube in the television camera and the enlarged image is either 

 viewed directly on a home receiver or projected on a screen by a thea- 

 ter projector. 



In all these instances compactness and simplicity of the television 

 camera are essential requirements. A great step forward in this di- 

 rection has been the recent development of the vidicon (6), a highly 

 sensitive television pick-up tube with a photoconductive target. This 

 tube, though only 1 inch in diameter, is capable of transmitting high- 

 quality television images at moderate light levels. Furthermore, the 

 extraordinary simplicity of the vidicon simplifies control of the cam- 

 era from a distance. In a typical example of present industrial tele- 

 vision equipment (7), the control unit incorporating a monitoring 

 kinescope is connected by a 500-foot cable to the camera. This cable 



