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[Contents]
Iconoscope
Chapter 6
- Television and RCA
1929-1934
In
late 1928, an event occurred that changed not only Zworykin’s
personal life but inevitably, the social life of twentieth century
man—if television can be considered, as I believe it to be,
one of the great cohesive social phenomena of this century. Zworykin
was sent to New York City by Mr. S[amuel] M. Kintner to meet David
Sarnoff, the noted communications pioneer and general manager
[vice president] of the Radio Corporation of America. Sarnoff, who rose
from the telegraph clerk who received the last message of the dying Titanic
to a visionary in the field of electronics, was quick to grasp the
impact of Zworykin’s new device. His subsequent support of
Zworykin ensured the eventual success of a practical electronic all
electronic television system.
My
first impression of Sarnoff was as a man of tremendous energy, drive,
and vision. He listened without interrupting my story, asked a few
questions to clear some points that I didn’t make
sufficiently clear, and then asked "How long it will take you to build
a system which will produce a picture better than the present results
with mechanical systems?" I remember telling him that given proper
facilities I hoped to do it in two years, since considerable progress
was done in the last years at Westinghouse. The next question was what
facilities I would need and how much it will cost. The last question
was the most difficult one and I estimated in terms of space and an
additional two engineers, which I estimated as a budget of an
additional $100,000 a year. Later in many of his speeches and
reminiscences of the history of television development, Sarnoff pointed
out the difference between this figure requested by me and many million
dollars spent by RCA on T.V. before it became a commercial success.
In
Sarnoff I found another dreamer of television, visualizing clearly how
it could be used when it became technically feasible. Sarnoff saw
television as a logical extension of radio broadcasting, which was
itself already commercially prosperous. The interview with Sarnoff
proved to be a turning point in television development. The laboratory
received some additional help and research began to move much faster.
Furthermore, I was permitted to deliver a paper describing our earlier
work on television before the Institute of Radio Engineers in Buffalo,
New York, in November 1929. The presentation attracted a very large (p.
89) audience and, since I could describe only the earlier part of our
work, a lively discussion ensued and many embarrassing questions were
asked that I was not permitted to answer. All during the discussion I
kept noticing a blackboard on which someone had written that I was
wanted on long distance. When finally I was able to call back our New
York office, I was told that the Patent Department had changed its mind
and withdrawn the permission for the paper. I answered that it was too
late, since the paper had already been presented. In the meantime I was
sent abroad by Westinghouse to visit some laboratories that were
contractually connected with their organization. I went to Paris and
revisited Professor
[Pierre] Langevin and the Laboratory
of Mme. [Marie] Curie.
There I met Dr. [Fernand] Holweck,
beginning a friendship that continued until his tragic death in
occupied Paris during the Second World War.
On
my return from abroad, I learned that as a result of a ruling of the
Anti-trust Commission, all work on communications had to be transferred
from Westinghouse and General Electric to the Radio Corporation of
America [RCA]. My personal dilemma was either to remain with
Westinghouse and continue working on some other problem, or to join RCA
and move to Camden, New Jersey. It meant breaking up my home again,
selling the house, and starting a new life. However, to continue my
work meant so much to me that I decided to move. Fortunately, most of
my group of engineers decided to move with me.
Moving
the laboratory was not a very easy task and the progress of the work
was delayed for several months. In Camden our laboratory was housed in
an old factory building that was not well suited for our purposes. We
had to improvise facilities which delayed even further the progress of
our work. In Camden we were joined by a group of General Electric
engineers (headed by Elmer
Engstrom) who had worked on television problems under Dr.
[Ernst] Alexanderson. As a result it was soon possible to
build a broadcast transmitter on the tower of the Camden City
Hall and to begin the actual testing of television broadcasting.
In
the following decade, hundreds and perhaps thousands of engineers all
over the world worked on refining an electronic television system, but
for all their work, it remained basically the same as it was in
Zworykin’s Camden Laboratory. Whatever variations were
made—they all included the Iconoscope’s fundamental
feature—the storage of light during the whole picture frame
time in a manner reminiscent of the operation of the human eye. (p. 90)
As Zworykin’s laboratory was enlarged, Zworykin and the
extraordinary group of young engineers he had gathered around him were
able to undertake some research of a more general nature, research that
Zworykin characterized as resulting from "scientific curiosity."
One
of them was the electronic image tube, a device to transform light
images into electronic images. Originally this work was
undertaken to study electron lenses for focusing the electron
beam into a small sharp spot in both the Kinescope and the Iconoscope.
We called the resulting tube an "Image Iconoscope." It became very
popular with television cameramen and is still used in many parts of
the world. The study of the effects of the bombardment by electrons of
different materials led us to the development of the electron
multiplier. We found that it was possible to amplify electron currents
millions of times by repeated bombardments of properly activated
targets. The electron multiplier was eventually applied to television
and is now a feature of modern pickup tubes. In the beginning we also
tried to use it in sound movie projectors; however, when cost analysis
indicated that it would cost more than conventional tube amplifiers,
the idea was ruled out.
The
history of the electron multiplier from its invention to its present
important place among modern scientific tools is a very interesting
one. For several years it remained a laboratory curiosity because it
was considered to be too expensive for practical application;
at that time the requirements for scientific application, such as
scintillation counters or in astronomy, were too limited to warrant its
production. We continued to make it in the laboratory and distributed a
few of them for tests among physicists and astronomers. However, soon
after the beginning of the war, we found that RCA received a large
contract for electron multipliers for secret purposes. The curious fact
is that the electron multiplier was invented as a low-noise amplifier
and found only limited use as such. After the war, we found that its
secret use was for a random noise generator to interfere with enemy
radar. One never knows how new inventions will be used.
The
character and scope of the work in the laboratory at this time
underwent a considerable change. Our group, initially constituting an
isolated laboratory devoted to the general problem of TV, became part
of a much larger group and concentrated largely on
electron-optical problems that were directly or indirectly connected
with TV. This afforded the opportunity of investigating more closely
some phenomena we observed earlier in our TV work. One of these was the
old problem of increased precision in the focusing and deflection of
electron beams, so important to the good production of TV pictures.
This revealed to us the remarkable analogy between the action of
magnetic and electrostatic fields on electrons and of lenses and prisms
on light. More and more we began to visualize the possibilities (p. 91)
of using electron-optical devices similar to well-known optical ones.
We
utilized electron lenses for the magnification of electron images at a
very early time for viewing a magnified image of the cathode on the
screen on Kinescope. This was the beginning of our interest in the
electron microscope, and several years later the first commercial
electron microscope was manufactured by RCA. (p. 92)
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