| Patent drawings to be downloaded as images:
.
Tihanyi Katalin
A TELEVÍZIÓ NAGY MAGYAR ÚTÖRŐJE
KATALIN TIHANYI GLASS
 THE
ICONOSCOPE: KALMAN TIHANYI AND THE DEVELOPMENT OF MODERN TELEVISION
(Revised June 23, 2000.)
Isaac Newton
Great sums have been paid out in lawyers'
fees and other costs to develop patent position giving them dominance. And dominance,
Insofar as RCA is concerned, is predicated upon the cathode ray scanner, the Iconoscope (1) .
Introduction
This article is the result of nearly
two decades of research into the history and development of modern electronic television.
The conclusions are drawn on primary source material, of which the most revealing have
been the archival files containing the original U.S. patent applications and related
correspondence by Kalman Tihanyi (2) and V. K. Zworykin (3),
and the Hungarian patent application, filed by Kalman Tihanyi on March 20, 1926 (4), still preserved at the National Archives in Budapest.
In addition to these heretofore unexamined
documents, the writer was greatly aided by the extraordinary cache of private letters and
other documents the Hungarian inventor left behind at his death in February 1947.
Canonical and other views
As the theme of the 1939 New York World's
Fair was the future and its technologies, no occasion would have been more fitting to
launch television, the much anticipated new medium of communication, than the opening
ceremony on Sunday, April 30, in the presence of the thousands who came to participate in
the celebrations. Indeed, those who were fortunate enough to not only hear President
Roosevelt's dedication speech but also see the historical telecast on receivers at the
pavilion of the Radio Corporation of America knew that they were witnessing the future
itself.
The new television transmitter that made
this possible was the iconoscope, a so-called "storage" tube, whose invention
was attributed to the Russian-born RCA engineer, V. K. Zworykin. This storage television
system and its further refined incarnations would prove a remarkably enduring concept,
considering that it is only now being replaced with new technology, digital television.
The attribution of the iconoscope to
Zworykin was the almost universally accepted view until the early 70's, especially in
America, where both the popular and the technical literature would usually list his 1923
patent application as the basis for the storage camera, and where articles written on
celebratory occasions would frequently talk about him as "the father of
television".
As for Zworykin's own publications about
the iconoscope and its later developed versions, although neither his important 1934
article, entitled "The Iconoscope - A Modern Version of the Electric Eye" nor
any of his subsequent writings claim the iconoscope outright as his own invention, this is
invariably implied between the lines (5). The hidden factors
surrounding the development of the iconoscope remained concealed for the next forty years.
Interestingly, a review of the European
historical literature published between the early 30's and early 70's reveals that the
authors are frequently equivocal regarding the origin of the storage principle and storage
television. Thus some writers credit the ubiquitously mentioned but never clearly
postulated "storage principle" to the Hungarian physicist, Kalman Tihanyi, and
the iconoscope to Zworykin (6), others speak of parallel invention. Yet
others take the curious position that "Tihanyi's invention was so far ahead of its
time that it was never realized" (7).
Two of these European publications, Prof.
Fritz Schröter's 1933 and 1937 surveys of television development, deserve special
attention, due to the author's involvement in television experiments as head of the
laboratories at Telefunken - in addition to his expert status as professor at the Berlin
Technical Institute - and because of his first-hand knowledge of the Hungarian inventor's
proposals regarding storage-based television.
In his comprehensive 1933 survey Schröter
dismisses electronic television plans in general and states that none of the solutions he
had discussed "have the chance of being realized in the foreseeable future,"
then adds:
"We can, however, justify a discussion
of these proposals by emphasizing a possibility of extraordinary significance: those
arrangements which, using the capacity of individual cells, permit the storage of light
effect; that is, arrangements where the control action of the time component of the light
effect is more than 1/n s (e.g. n = 16) provide possibly the only attainable future
solution for transmission of pictures of normal brightness" (8).
Thus in this book, professor Schröter, to
whom Tihanyi had personally disclosed his inventions in the summer of 1928 (9)--when
he declined to recommend it for development by Telefunken, despite his obvious initial
enthusiasm (10)--while clearly analyzing the difference between
non-storage plans and storage technology, mentions Tihanyi among the inventors who had
proposed the former (Schoultz, Seguin, Zworykin, Sabbah, von Cordelli). It is worth noting
that Schröter, in the same book, praising Zworykin's achievements in the area of
electronic television receivers, describes his efforts regarding television transmission
as "unrealized proposals".
Although protests by Kalman Tihanyi led to
corrections in Schröter's next book (11) - this time giving credit
for the "concept of the storage principle" to Tihanyi and for the
"technical solution" to Zworykin, with frequent references made to
"Zworykin's iconoscope" - as historian Paul Vajda later observed, the author
"again suppressed the fact that precisely what was new in this transmission tube, the
charge storage, was Kalman Tihanyi's invention" (12).
This slanted presentation could perhaps be
ascribed to the increasingly strong relationship between Telefunken and RCA, and the
disingenuous information received through Zworykin (13) and RCA public
relations releases, in addition to a possible desire to justify Telefunken having turned
down Tihanyi in 1928. It is namely quite clear that based on the only patent issued to
Zworykin, his 1925 application, for a television transmitter (14)
preceding the book's publication, there was no evidence of his priority with regard to
storage technology. Since logic would dictate that Zworykin's still pending 1923
application did not describe a more advanced technology, Schröter's treatment of the
issue was certainly not based on hard evidence.
This treatment elicited further protest
from Tihanyi, who, in two letters to Schröter (15), defended his
authorship and again demanded correction, pointing to his 1926 Hungarian application and
his 1928 patents as the origin of both the storage concept and storage television
technology (16). In an April 1940 response to a letter from Schröter,
Tihanyi writes:
"Please be kind enough to take into
consideration that, for years, Zworykin was unable to produce any practical result based
on his own plans, despite the fact that he had the giant laboratories of RCA at his
disposal, and that he was only able to develop the image storage tube after the
publication of my plans.
On studying the Zworykin patents, it
becomes clear that these plans do not contain practically viable proposals. For reasons
yet to be clarified, Prof. Schröter, you at one time declined to develop the image
storage tube according to my plans".
Tihanyi's correspondence with Schröter and
others continued throughout the war (17). In a 1942 letter to Prof.
Viktor Babits, the inventor indicated he was planning to demand proof of authorship form
Zworykin "once the war is over and there is overseas mail delivery to the U.S.A.
again, chiefly on the grounds of the covert plagiarism Zworykin has committed by
publishing as his own the practical solution RCA had purchased from me". However, he
was prevented from the execution of this plan by his death in February 1947, just as,
following the wartime blackout on all civil manufacturing, RCA resumed television
development.
The process of clarification began anew
when Dr. Paul Vajda, historian, took up the issue regarding the genesis of the iconoscope
for reevaluation in a number of books and articles (18). His
assessment of Tihanyi's and Zworykin's contribution to storage technology was entirely at
odds with the canonical view. Thus in his guide to a 1973 exhibit entitled "Great
Hungarian Inventors" and mounted by the Hungarian Museum for Science and Industry,
here is what Dr. Vajda had to say:
"Based on the study of the patent and
technical literature, it can be unequivocally concluded that the iconoscope, the first
television transmitter which embodied the storage principle, was invented by Kalman
Tihanyi in the 1920's. It was on the basis of Tihanyi's inventions Zworykin developed the
iconoscope, the transmitting tube based on charge storage, at the laboratories of the
Radio Corporation of America (RCA) which bought Tihanyi's inventions. In his patents not
only did Tihanyi formulate clearly the storage principle, but described its practical
solution as well. Tihanyi was the first who in his 1928 patents employed an adapter tube
at the transmitter, making scanning on the picture side possible, which in turn was the
fundamental condition for modern transmitters" (19).
Beginning with the mid-seventies the
Zworykin legend became the subject of scrutiny and serious investigation in America as
well. Questions were raised regarding Zworykin's contributions and, persuaded by the
previously unexamined documents which had come to light, a number of authors suggested
that Zworykin may not be the inventor of the iconoscope after all, and that the invention
of storage television should be attributed to the Hungarian physicist, Kalman Tihanyi (20).
As a result of the debate regarding
Zworykin's contributions, a certain confusion can be detected in more recent popular
writings on the subject, with the People's Almanac being just about the only publication
which continues to list the iconoscope as a 1923 Zworykin invention.
Thus, depending on the source, we may learn
that the year when Zworykin invented, or "developed," or "constructed"
the iconoscope was 1928 (Smithsonian Institution), 1931 (Encyclopedia Americana; A.
Abramson; F. Lovece; P. Farnsworth), 1933 (Los Angeles Times), and 1938 (Isaac Asimov). It
is currently acknowledged that the first Zworykin applications which show storage-related
technology date from 1930, and that the application showing specific characteristics of
the iconoscope was filed in 1931, five years after Tihanyi's 1926 application and three
years after Tihanyi's 1928 applications describing further refined versions of storage
technology.
Table of Contents
Early electronic television
As is well known, television is transmitted
by "scanning" a screen, also called "image carrier" or
"target," upon which the image is projected. This scanning is accomplished by
the cathode ray which explores the screen point by point and line by line. The method of
transmitting pictures by breaking them down into elemental areas and reassembling the
electrical impulses representing these individual points at the receiving side, had been
suggested by the German inventor Paul Nipkow in 1884 (21). Although
Nipkow's was a mechanical device, the idea of scanning has never been replaced by a better
one.
The idea for the image carrier itself, a
device which would use the human eye as a model, was first suggested by Ayrton and Perry
in 1877. They published their plan in 1880, proposing to build a large mechanical eye with
selenium cells as the retina.
But, as with all "seeing,"
whether the medium is the retina of the eye a photographic plate, or a television target,
of crucial consequence for "picture definition" is the medium itself and the
time it is exposed to the light from the image. Of this logically follows that the
television camera, and within it its target, in effect its "eye," is the most
important element for good television transmission. The task of creating a device which
would accomplish "seeing" at distances the human eye could not span proved to be
a formidable challenge.
To illustrate the difficulty of what had to
be accomplished in order to make viable television transmitting devices, let us quote
verbatim the first of two letters, published in Nature on June 18, 1908, by A. A. Campbell
Swinton, the first proposal suggesting the use of cathode ray tubes at both the
transmitting and receiving side, thus what is commonly thought of as
"electronic" television:
Table of Contents
"DISTANT ELECTRIC VISION"
Referring to Mr. Shelford Bidwell's
illuminating communication on this subject published in Nature on June 4, may I point out
that though, as stated by Mr. Bidwell, it is wildly impracticable to effect even 160.000
synchronized operations per second by ordinary mechanical means, this part of the problem
of obtaining distant electric vision can probably be solved by the employment of two beams
of kathode rays (one at the transmitting and one at the receiving station) synchronously
deflected by the varying fields of two electromagnets placed at right angles to one
another and energized by two alternating electric currents of widely different
frequencies, so that the moving extremities of the two beams are caused to sweep
synchronously over the whole of the required surfaces within the one-tenth of a second
necessary to take advantage of visual persistence.
Indeed, as far as the receiving apparatus
in concerned, the moving kathode beam has only to be arranged to impinge on a sufficiently
sensitive fluorescent screen, and given suitable variations in its intensity, to obtain
the desired results.
The real difficulties lie in devising an
efficient transmitter which, under the influence of light and shade, shall sufficiently
vary the transmitted electric current so as to produce the necessary alterations in the
intensity of the cathode beam of the receiver, and further in making this transmitter
sufficiently rapid in its action to respond to the 160,000 variations per second that are
necessary as a minimum.
Possibly no photoelectric phenomenon at
present known will provide what is required in this respect, but should something suitable
be discovered, distant electric vision will, I think, come within the region of
possibility".
On December 7, 1911, A. A. Campbell Swinton
returned to the subject in an article published, again, in Nature (22).
This time, he gave a detailed description
of the all-electronic television system he had in mind, specifying two Crookes tubes
filled with gas or sodium vapor which, it had been proven, would conduct the negative
electrons discharged by the photosensitive layer of the screen under the influence of
light (photoelectric effect) more readily than in the dark. At the transmitting side, the
magnetically deflected cathode beam would explore a screen upon which the image was
projected through a wire gauze, and transmit the electrical charges -- emitted by the
photosensitive layer at each successive point the cathode ray touched -- to the receiver.
Campbell Swinton, however, admitted that this method of transmission and reproduction of
the image would only work, provided "all portions of the image were at rest" and
added:
"...the somewhat crude form of
photoelectric cell described, composed merely of insulated cubes of rubidium in contact
with sodium vapor, might be improved upon. Indeed, it is highly probable that research
will reveal much more sensitive materials, the use of which would vastly improve this part
of the apparatus, which at present is probably the one least likely to give the desired
results".
Interestingly enough, it has been suggested
that the Campbell Swinton proposal anticipated the storage principle. This view, however,
is based on the failure or reluctance to recognize that true storage depended on an
entirely different mode of operation and several new key elements which, as Campbell
Swinton predicted, had to be added to the device he described in his seminal paper.
Namely, although one could argue, as has
been done, that the individual photosensitive areas of the screen would accumulate and
"store" positive charges, Schröter, Zworykin and others agree that the output
would be too small for any practical purpose. The reason for this is the minute capacity
of the individual photocells and, as in Campbell Swinton's proposal, the absence of a
collecting electrode which would capture the electrons emitted by the photosensitive layer
and thus allow continuous accumulation of new positive charges between scansions (23). Thus the minute capacity of the photocells would result in their
rapid "saturation," completed as it were long before the maximum light effect
corresponding to the brightest areas of the image could be achieved.
It can be established, then, that early
electronic television as suggested by Campbell Swinton still depended on scanning, the
utilization of photosensitive materials for the image carrier, and the photoelectric
effect -- that is, the liberation of electrons form certain metals under the influence of
light. The replacement, however, of Nipkow's mechanical scanner with the swift and
weightless cathode ray and the employment of cathode ray tubes at both the transmitting
and the receiving side proved revolutionary advances which endured to our day. The
improvements that Campbell Swinton predicted would be necessary to render the image
carrier and, with it, television a practically viable instrument would be supplied by the
concept of "storage".
Table of Contents
Zworykin's 1923 patent application
While the Zworykin proposal as originally
specified in 1923 also featured gas filled tubes, that is, not vacuum technology, it
differed from the Campbell Swinton device in that an insulating layer was added between
the photosensitive layer and the conducting back plate. The scanning beam impinged on the
back plate; the highly resistant metal insulation would only allow electrons to pass from
the photosensitive layer of the screen when and at the point the cathode ray penetrated
the back plate and thus established a conductive connection between the two. Consequently,
as was the case with the Campbell Swinton proposal but for different reasons, the Zworykin
system relied also on the minute local capacity of the individual photoelectric cells.
At the time, however -- and as the archival
documents reveal through the next few years -- this arrangement was not seen by Zworykin
as a detriment. Ten years later in his 1934 paper, however, with the benefit of hindsight
seeing clearly what he had obviously not seen before, Zworykin showed with computations
"how microscopic would be the output of the photocell" with such means and under
such operational conditions. What Zworykin failed to note in this paper was that, as
originally filed, his own 1923 application described exactly the type of technology that
would yield the result he had just illustrated.
As Paul Vajda observed, these early
electronic television transmitters and receivers were analogous to mechanical television
devices (Nipkow, etc.) in their operation and the resulting charge or current output. For
this reason, Vaj-da, very aptly, characterized them as "linear" or
"electromechanical" systems. Zworykin had characterized these early television
system as "instantaneous" devices, referring to the fact that, as in mechanical
systems, they utilized merely the instantaneous charges released by the action of the
light on the photocells during the infinitesimally short time the cathode ray impinged
upon them as it explored the screen (24).
The first demonstration of a television
system based on the 1923 Zworykin plan is assumed to have taken place sometime in 1925,
while he was still employed by Westinghouse. Various accounts of this event, including
Zworykin's own, report that a barely discernible "X" mark was produced on the
receiving screen. Several sources agree with historian Albert Abramson's account (25) (based on Westinghouse Research Report #R429A, marked
"confidential") that following the demonstration Zworykin was instructed to
"work on something more practical". It seems he subsequently did not participate
in any of Westinghouse television projects, which were headed by Dr. Frank Conrad.
Table of Contents
The storage principle
Much as it has been cited in historical
accounts, the curious will search in vain in standard physics textbooks and reference
books for a postulate of the "storage principle," and though we often encounter
the accurate albeit superficial explanation that under this principle the accumulation of
charges continues during the entire scansion cycle, how this is done it not clearly
explained.
The earliest reference to the new
phenomenon this writer found is in an article, entitled "About the Electrical
Television," written by Kalman Tihanyi and published on May 3, 1925, nearly one year
prior to his first application for patent on an all-electronic television system. Although
the inventor does not use the term "storage principle" of "storage
effect," the description of the new phenomenon he had discovered implies that that is
exactly what he had in mind. Thus, he wrote:
"The writer of this article has
studied thoroughly all phenomena known from the current state of the physical sciences
which could be applied to the solution of the problem and on the basis of control
calculations found them unfit for the achievement of the minimally required 1/80,000 s
efficiency at the transmitting station. However, during experimentation a new physical
phenomenon was discovered, under which the optical and the electrical effect is
practically simultaneous. In fact displacement between the two effects could not be
detected with our instruments, although the possibility exists for a displacement of
1/400,000,000 of a second based on Maxwell's equations in regard to a related phenomenon.
This means that under this phenomenon not only the desirable 1/150,000 second changes, but
1/400 million changes can be followed" (26). (Emphasis added.)
An investigation of various dictionaries
and lexicons confirms that, indeed, in addition to the photoelectric (or photoemissive)
effect, storage television technology also involves an entirely different phenomenon.
Evident from these characterizations is
that while under the photoelectric effect bound electrons released from such
photosensitive materials vary linearly with the frequency of the radiation, "that is
for each incident photon an electron is ejected," under the storage effect a
photoconductive and photovoltaic phenomenon occurs where ("apart from the liberation
of electrons from metals") when photons are absorbed in a p-n junction (in a
semiconductor) or metal-semiconductor junction, "new free charge carriers are
produced," (photoconductive effect) and where "the electric field in the
junction region causes the new charge carriers to move, creating a flow of current in an
external circuit without the need for a battery," (photovoltaic effect) (27).
The Concise Dictionary of Physics
under the heading, "Photoelectric Cells," differentiates between "the
original photocells" (which utilized photoemission form a photosensitive surface
and their attraction by the anode) and "the more modern photocells which
utilize the photoconductive and photovoltaic effect" (28).
Table of Contents
The advent of storage based television
Simply put, the essence of storage
technology is that the television signal, rather than being the equivalent to the input
charges and the product of primary electron emission, is produced by the secondary
emission resulting from several stages of amplification. Contrary then to early electronic
television devices which, as we have seen, rely on the minute local capacity of the
photoelectric layer -- even under conditions where the image carrier is exposed to the
light from the image during the entire scansion cycle -- a number of major innovations
have been added that make true storage possible:
- the addition of the third electrode, a positively charged
grid before, or as part of the screen. This grid electrode opens "the
valve," so to say, to the continuous flow of electrons -- taking over the control of
the electron flow passing from the photosensitive layer through a partially conducting
dielectric layer to the collecting electrode, the so-called "signal plate"
throughout the scansion cycle -- and acts as an amplifier. The time available for
accumulation of charges is on the order of the number of picture elements;
- the replacement of (Zworykin's) high insulation with the
partially conducting dielectric layer which also allows continuous electron flow, and
produces an increase in the capacitance of the condenser -- i.e. new free charge carriers
are produced in the semiconductor and in the metal-semiconductor junctions of the screen
-- and thus a further increase of electric charges. The increase within the semiconducting
layer is determined by the dielectric constant (relative permittivity) of the given
material. Thus in the case of glass having a dielectric constant of 5, and mica having a
dielectric constant of 7, a five-fold respective seven-fold increase of charges will
result. The insulating layer used in the first storage tubes was glass, lacquer, or
vitreous enamel; in iconoscopes, mica.
In addition, storage technology provided:
- "electrostatic focusing," that is improved
picture definition through an increase in the number of picture elements, achieved through
the "thinning" or concentration of the cathode beam into a very fine spot by
having it pass through a "sleeve" of opposing electrical field that prevents
diffraction. Thus it is the size of the scanning spot rather than the physical subdivision
of the photosensitive layer that defines the size of the individual picture elements, and
in turn the number of lines. [Iconoscopes, according to Zworykin's 1934 paper, were good
up to 500 lines, while the mechanical camera demonstrated by him in July of 1930 featured
80-line scanning (29)];
- "single-sided scanning," characteristic of
the first iconoscopes, made possible by a reflecting image carrier, and the cathode beam
striking the front or photosensitive side of the screen at a 30 degree angle, which
in turn was made possible by the elongated neck, the adapter tube, placed at this angle in
relationship to the body of the tube.
Table of Contents
The patents of Kalman Tihanyi
A thorough study of the contemporary patent
literature reveals that the concept of storage and the detailed description of the
technology which already utilizes the storage effect, as characterized above, was first
disclosed by Kalman Tihanyi in his T 3768 Hungarian patent application, filed on March 20,
1926.
Although "single-sided operation"
would be added in the inventor's further refined 1928 applications, in this patent
Tihanyi describes all elements and the mode of operation necessary for the implementation
of the storage effect within television transmission and receiving systems. Ha defines
the task he set for himself as follows:
"In order to solve the problem of
electronic television, primarily a new system is needed, which extends the life cycle
of the picture elements themselves at least to 1/100 s, but preferably to the maximum
1/10 s, that is for the life cycle of a picture, so that at the same time electric pulses
of a given life cycle suffice for their control".
For the increase of the local capacity of
individual photoelectric cells he proposes an image carrier -- either bar bundle type or a
composite screen -- which is a triode, consisting, at the transmitter, of a
positively charged control grid mounted on a glass or lacquer insulation layer;
photosensitive layer, and platinum collector electrode. At the receiving side, the
luminescent screen is also connected to a control grid and is applied onto a micanite
insulating layer.
Both the grid electrode and the partially
conducting mica layer serve to increase electron emission, while allowing continuous
electron flow and resulting storage of accumulated charges continuing during the scansion
period between discharge by the cathode ray beam.
This storage action, then, occurs both at
the transmitting and the receiving side (30).
As mentioned above, single-sided operation
was introduced in the inventor's 1928-1929 applications. In addition to this, in these
applications the following improvements were added:
- homogenization of the cathode ray
- the employment of extreme vacuum
- various means for increasing the brightness of
phosphorescent screens
- electrical picture amplification
On August 26, 1930, Tihanyi added a newly
formulated claim no. 1 to the first of his two U.S. applications (June 11, 1928 conv.
date). This claim represented the precise characterization of the device, and defined its
operation:
"Transmitting and receiving tube for
electric television apparatus, by which one or more light sensitive image carriers in
which the various points of a picture projected thereon produce different electric changes
of condition, are scanned point for point by an electricity carrying pencil of rays,
characterized by the feature that the picture shading impulses are imparted to three or
more grids, preferably diaphragms, and that the grids are so arranged that between
successive grids opposite fields are formed."
In his second patent specification, British
patent No. 315, 362, (and U.S. patent application, serial no. 377, 261) frequently omitted
from the literature, the inventor describes various proposals for mosaic screens (targets)
utilizing the photoconductive and photovoltaic effects. Most likely, these proposals
constitute the basis of further improved iconoscopes including the vidikon, the
transmitting tube representing photoconductive and photovoltaic technology. On page 7 of
the British patent specification here is how the inventor introduces the description of
these devices:
"In Fig. 34 to 40 various transmitting
tubes with photo-ohmic image carriers are shown. In a photo-ohmic image carrier substances
are used which change their electric conductivity when acted on by light. The reaction
inertia of these substances is not detrimental as the whole picture is projected onto them
at the same time and the individual points of the projected picture act on the photo-ohmic
layer for a relatively long time, for instance 1/30 of second".
Characteristic for the wealth of the
material, i.e. the number of innovations included in this application, is the request from
the U.S. Patent Office for its division into six patents (31). Aside
from the many different constructional forms of photoelectric, photo-ohmic, photo-ohmic
grid, transparent and light-sensitive crystal image carriers for both single-sided and
two-sided operation, it describes at least seven means for picture intensification,
including self-increasing, multi-stage and secondary picture intensification. In light of
this -- and, as we will see, Zworykin's knowledge of Tihanyi's priority patents since at
least 1930 -- the absence of even the slightest acknowledgement in the 1934, 1937 and 1939
papers authored or coauthored by Zworykin, with the credit for these innovations
distributed to various RCA workers' much later patent applications, seems a glaring
misrepresentation of the facts.
Table of Contents
The trials of an independent
inventor
With a grant which enabled him to travel
abroad in the hope of selling his patents, Kalman Tihanyi arrived in Berlin in June of
1928. Prior to this, he had presented his television plans to Prof. Emmerich Poeschl (32) and, in April 1927, in Vienna, to Prof. Schweiger, head of the
Austrian Radio's laboratories, who invited him to conduct experiments at the labs and gave
him a letter of recommendation to Count Arco, founding director of Telefunken (33).
Diary notes from 1928 reveal that the
inventor gave detailed information about his plans first to Count Arco and Schröter,
subsequently (in a meeting with the director, chief engineers and patent attorneys) to
Siemens, as well as to professors Karolus and Korn, and thereafter to just about all other
companies in Berlin - and, judged by his letters, later in London - involved in work on
(mechanical) television systems.
Historically, it is interesting to note
that despite the initial enthusiasm for his entirely novel solutions to the problem of
television, all of them decided to continue experimenting with mechanical television
systems until the mid to late thirties, at which time they discarded these efforts in
favor of storage television, for which they ended up paying royalties to RCA.
While the negotiations in Berlin continued
through 1929 and Tihanyi accepted an offer from Siemens to provide improvements for their
(Karolus) picture telegraph, on August 8, respective September 4, 1929, the very extensive
abstracts of his British patent specifications were published in the Illustrated Official
Journal (Patents). Shortly thereafter, patent to his French application was issued; the
patent was published in February 1930. As a result of these publications, Kalman Tihanyi's
plans were accessible to all workers in the field.
Letters written by the inventor (34) indicate that word of RCA's interest in his patents reached him at
the end of July 1930. Apparently, after an extensive search, RCA located him in London,
where he was at work on the prototype of his photoelectric torpedo -- a television guided
pilotless miniature airplane that could see, follow, and destroy moving targets -- under
contract with the British Air Ministry (35). Negotiations with RCA
continued throughout 1931 in London, and, after a meeting between the inventor and RCA's
European manager, G.A. Morton on or around February 4, 1932 throughout Tihanyi's stay in
Italy to develop the prototype of the self-directing camera for the Italian navy (36).
Table of Contents
The development of the iconoscope
It would seem that the search for Tihanyi
began following Zworykin's move, in the spring of 1930, from Westinghouse to the RCA labs
and the publication of Tihanyi's French patent No. 676,546. At that time, Zworykin resumed
his television experiments, concentrating on certain new ideas regarding receiving tubes
with which, according to Albert Abramson's account, he returned after an extensive tour in
the summer of 1928 of Europe's television laboratories (37). (It is
interesting to contemplate what Zworykin might have heard about Tihanyi's ideas in Berlin
where, no doubt, he visited the same places and almost simultaneously with the Hungarian
inventor.)
Apparently, the ideas with which Zworykin
was inspired at the Belin laboratory in Paris took shape in his November 16, 1929
application (U.S. Pat, 2,109,245) to which the canonical view attributes the Kinescope.
The pivotal feature of the invention seems to be the electrostatic focusing
("thinning of the pencil of rays" in the 1926 and 1928 Tihanyi patents) (38).
On May 1, 1930, Zworykin applied for a
patent describing a complete television system (39). A second patent
application was filed on July 17, 1930 (40). Both applications are an
attempt at storage featuring two-sided targets -- that is the cathode beam impinges on the
back plate. Both specify 6.400 picture elements.
These applications run into difficulties at
the patent office, as the examiner rejects six claims, citing Tihanyi's 313, 456 and 315,
362 British patents and the fact that these were "thrown open to the public in
England on June 26, respective July 24, 1929" (41). Eventually,
fourteen claims of the May application and three, then six more claims of the July
application were rejected on this basis.
The latter were subsequently restored based
on fully spurious reasons.
Zworykin's first demonstration for RCA took
place on July 15, 1930. According to Abramson, although if featured an electronic
receiving tube, the television film transmitter was a mechanical device (Nipkow disk) and
syncronization was accomplished by a mechanical impulse generator. Another more recent
publication, Prof. J. H. Udelson's survey of the development of television in America,
confirms this (42).
Apparently, the Zworykin group began the
transmitter experiments by attempting to build a camera tube based on Zworykin's July 14,
1930 appliation. Again, in Abramson's reconstruction of the events around this time:
"...the Zworykin group at RCA was having very little success with its two-sided
camera tubes". The turning point came almost a year later in May 1931 when it was
decided, according to Abramson around May 14, 1931, "to- investigate the single-sided
target," that is, the technology which was characteristic for the first iconoscopes.
We further learn that according to Zworykin's notebook, "by June 12, 1931, several
tubes had been built that were giving quite promising results, and it was decided to
proceed along these lines" and that by September or early October "the group at
Camden was making excellent progress with the new single-sided camera tube".
Apparently, so much so that on October 23, 1931 it was decided the new camera would be
called Iconoscope (43). A relevant detail confirmed both before and
after Abramson: the name "iconoscope" was given the new device on October 23,
1931.
As the archival files show, in late 1931
Zworykin began to file amendments to his still pending 1923 application, on which there
had been no action since 1926. These amendments featured radical revisions,
primarily to the important "claims" (44) section,
introducing language associated with storage technology and explaining how the new
terminology fitted the originally specified elements and operation. Likewise, after that
first blush of success in June, a series of revisions were initiated to the May 1 and July
17, 1930 applications.
On November 13, 1931, Zworykin filed yet
another patent application. A reading of this patent and its archival files reveals that
though it describes a device which is "capable of making visible objects so small as
to be otherwise invisible to the eye" (an electron microscope?) the subject of
controversy became the television camera it specified, featuring single-sided scanning,
mica insulation, platinum collector electrode, and other features characteristic for
iconoscopes (45).
Thus in August 1934, six claims were denied
to this application due to cited prior conception by Tihanyi and cited publication of his
two British patents in 1929 (46). These claims sought to protect
priority to single-sided scanning, the adapter tube (the elongated auxiliary tube which
makes possible single-sided scanning), and other features associated with the iconoscope.
This last effort by Zworykin and RCA to
secure the right to the single-sided technology thus defeated, RCA had a camera tube at
last, but no control over the rights to the technology. By this time, however,
negotiations with Tihanyi had been resumed.
Less than three weeks later, according to a
September 13, 1934 letter by Tihanyi, an agreement had been signed between himself and
RCA. By then, it seems, RCA was manufacturing iconoscopes based on his patents. Namely, as
we learn from Abramson, in U.S. Pat. No. 2,047,369, filed in December 1934 by W. Hickok of
RCA for a photoelectric device, the inventor stated that the image carrier described in
Kalman Tihanyi's copending application "was the type usually constructed" (47).
In early February 1935, "urgent"
cables from RCA to Tihanyi indicate that company representatives arrived in Budapest for
the signature of additional papers and that these were signed on February 15th. On March
8, the Tihanyi application was revived and filed as two separate applications, transmitter
and receiver, now under RCA aegis. On March 13, RCA filed an application for the trademark
"Iconoscope," curiously enough, claiming use of the name only since February 13,
1935 (48).
Archival files of the Tihanyi transmitter
application, U.S. Pat. 2,158,259, and of the November 13, 1931 Zworykin application seem
to indicate that the struggle to secure for the Zworykin patent at least some of the
claims related to the iconoscope technology must have continued after the August 1934
rejection by the examiner. But on March 18, 1935, RCA attorney H. G. Grover stated on
behalf of Tihanyi that four of the six claims previously denied the Zworykin application
would be "canceled from the Zworykin patent in that the common assignee will elect to
prosecute the said claims in this application", that is in the Tihanyi application
whence it was taken originally (49). In an April 9, 1935 brief to the
Commissioner of Patents, RCA attorney R. Goldsborough on behalf on Zworykin, canceled all
six claims "in view of the examiner's rejection of the same on Figure 9 on Tihanyi
313, 456," the first of the two British patents (50). These
briefs signify the final capitulation of the effort to persuade the U.S. Patent Office
regarding Zworykin's priority to controlling features of the iconoscope.
Parallel with these developments and
entirely contradicting what went on in the patent office, Zworykin's prestige grew at an
accelerated pace following the January 1934 publication of his paper, "The Iconoscope
- A Modern Version of The Electric Eye" in the Proceedings of the Institute of Radio
Engineers. The introduction to the article established the link to the 1923 patent. It
said:
"This paper gives a preliminary
outline of work with a device which is truly and electric eye, the iconoscope, as a means
of viewing a scene for television transmission and similar applications. It required ten
years to bring the original idea to its present state of perfection".
But while Zworykin's rendition of
television's development was further propagated and gained almost universal acceptance,
his 1923 application itself was embroiled in a series of interference proceedings Zworykin
had initiated against rival inventors, including Philo Farnsworth, with most of these
cases ending in defeat. The transcript of the 1934 Final hearing in the Patent
Interference Farnsworth v. Zworykin is a rare document whose testimonies and decision are
highly relevant to the conlusions of this article (51). In 1938,
however, Zworykin's claim to priority was finally legitimized when, being judged the
winning party of an interference against another inventor, H. J. Round, on a minor issue,
the District Court of Delaware Issued patent on his 1923 application.
Of course, no one had reason to doubt that
the text as eventually published in the U.S. Patent Office Gazette corresponded to the
text of the application as filed. On the one hand, this is accepted practice, on the
other, the Zworykin patent's claims section and the abstract, as published on December
20, 1938, seems to describe storage technology. The truth, the complete
transformation through the years of the original claims section - where practically all
claims had been replaced with new ones - despite the obvious inconsistency between them
and the narrative description, remained a well-guarded secret for the next forty years.
Thus based on the documents which have come
to light, it is evident that neither the devices nor the conditions for storage technology
were specified in the 1923 -- and in his 1945 application -- Zworykin patent and that
these ideas did not occur to him, even in rudimentary form, until sometime in 1930,
following publication of the Tihanyi patents.
Paul Vajda's opinion, namely, that what was
new in the iconoscope was invented by Kalman Tihanyi and that it was on the basis of
Tihanyi's inventions Zworykin developed the iconoscope at the laboratories of RCA, is born
out by the documents.
Based on these documents it becomes obvious
that any survey of television's development is incomplete and distorted without an
examination of the Tihanyi patents.
Table of Contents
Kalman Tihanyi (1897-1947)
Kalman Tihanyi studied in Pozsony and
Budapest. By age fifteen, he had several small inventions, and was only seventeen years
old when he sold his patented remote control for city lights to a Viennese manufacturer. A
list of "Future projects" dating from the same year included: device for the
prevention of train collision, hydrogen-oxygen motor; scanner with selenium cells against
the grounding of ships; automatically guided torpedo; remote controlled submarine boat and
submarine mine. Interestingly enough, all these projects were later realized.
During World War I, Tihanyi served as
artillery engineer, then as radio engineer at the Austro-Hungarian Navy Headquarters in
Pola, where his remote controlled submarine mine was developed and successfully used. It
was subsequently honored as an outstanding military invention.
Though his preoccupation with the problem
of television goes back to at least 1917, it was not until 1924 that Tihanyi found the
solution he was looking for and began conducting experiments. By April 1925, he had
confirmed the soundness of his plans; on March 20, 1926, he applied for his first
television patent, introducing the concept of "storage".
In 1928, having refined the invention,
Tihanyi filed new patent applications that would later become the basis for the
iconoscope, then left for Berlin, according to his own account, with a suitcaseful of
inventions. Although Siemens, Telefunken and others rejected his storage television
system, he succeeded in selling patents for his loudspeaker, television receiver, and
short wave radio.
In the beginning of 1930, Tihanyi moved to
London at the invitation of the British Air Ministry to build a prototype of his aerial
torpedo, whose plans he had completed in Berlin. Later that same year, he learned of RCA's
interest in his television patents. While working on the aerial torpedo and negotiating
with RCA, he conducted negotiations regarding various other inventions as well:
wide-screen and stereo film, a reflector for submarines, etc.
At the end of 1931, Tihanyi was invited by
the Italian Navy to develop his torpedo for marine use. During the next three years, he
divided his time between the laboratories of the Air Ministry in London and the
laboratories of the Italian Navy off the harbor of Genoa, on Isola Castagna. In September
1934 he signed the contract with RCA regarding his television patents.
In 1935, Tihanyi began to work on
applications of hyper-energy ultrasound for rain-inducing irradiation of clouds and the
large-scale eradication of harmful insects The completed plan described an ultrasound
reflector with a range of 5-8 kilometers in the air and 400 kilometers in water.
In 1940, Tihanyi returned to Hungary and in
late 1941 began construction of the full-scale prototype. At the same time, he became
involved with the Resistance and developed an intimate friendship with its leader Endre
Bajcsy-Zsilinszky. In 1941, he was briefly arrested in connection with propaganda material
against Hitler and Basch; in 1943 his home was searched.
Following Hungary's March 19, 1944
occupation by the Germans, Kalman Tihanyi was arrested by the Gestapo and imprisoned at
the Margit Ring prison. Although he survived five months of solitary confinement,
starvation and interrogations, following the failed attempt at armistice on October 15th
by Regent Miklós Horthy and the installation of the Szálasi government, like the rest of
the Resistance, he went underground.
After the war, during the barely two years
until his death in February 1947, he began manufacturing his (hollow) ballbearings,
developed the prototype of a centrifuge which would separate and collect gold and other
metal particles from sand, volcanic ash, river beds, etc., and worked on various ideas
regarding nuclear defense.
At his death, he left behind a large number
of inventions. Those he deemed most valuable were almost without exception conceived
between 1935 and 1940. These included a sound abatement device and sound abatement wall,
energy-saving light-bulbs, device for the separation of infrared waves from light waves,
magnetostrictive telephone, sonar detector and a cluster of other inventions based on
ultrasound technology, among them a device for the elimination of carbon monoxide
emission. These manuscripts were marked: "To be saved for peacetime".
Note: Technikatörténeti Szemle (Review
of Technics) is published by Országos Műszaki Múzeum, the National Museum for Science
and Technology, Budapest
Table of Contents
Endnotes and Literature
- F. C. Waldorf and J. Borkin: Television:
A Struggle for Power, New York 1936. pp. 239.
- Archival files, United States Patent and
Trademark Office, Washington, D.C.: U.S. Pat. 2,133,123/June 10, 1929 and U.S. Pat.
2,158,259/June 10, 1929.
- Archival files, United States Patent and
Trademark Office, Washington, D.C.: U.S. Pat. 2,141,059/December 29, 1923; U.S. Pat.
2,246,283/May 1, 1930; U.S. Pat. 2,157,048/July 17. 1930; U.S. Pat. 2,021,907/November 13,
1931.
- K. Tihanyi: Hungarian patent application
T-3768/March 20, 1926.
- V. K. Zworykin, G. A. Morton, and I. E.
Flory: "Theory And Performance Of The Iconoscope." = Proceedings of the
Institute of Radio Engineers, August 1937; Harley lams, G. A. Morton, and V. K. Zworykin:
"The Image Iconoscope." = Proceedings of the Institute of Radio Engineers,
September 1939; V. K. Zworykin, G. A. Morton: Television. The Electronics of Image
Transmission, New York 1940.
- V. Babits: A távolbalátás és az
ultrarövid hullámok technológiája, (Television and the technology of ultrashort waves)
Budapest 1947, pp. 65-67. Although prof. Babits speaks about "Zworykin's
iconoscope," he states: "the famous ‘storage principle' appears first in (the
above) cited patents of Kalman Tihanyi".
- Letter from Prof. Walter Bruch to me,
dated Sept. 23, 1983. This statement is all the more curious as, according to the letter,
K. Tihanyi contacted Prof. Bruch in 1937 and must have mentioned the purchase of his
patents by RCA.
- F. Schröter: Handbuch der
Bildtelegraphie und des Fernsehens, Berlin 1933, p. 61.
- Diary notes from June and July 1928,
Kalman Tihanyi (The author's property.)
- Prof. F. Schröter's letter to Kalman
Tihanyi, dated July 10. 1928.
- F. Schröter: Fernsehen. Die neue
Entwicklungen insbesondere der deutschen Fernsehtechnik, Berlin 1937, p. 123.
- P. Vajda: "Újabb adatok a
hiradástechnika magyar úttörőire vonatkozóan" ("New data regarding the
Hungarian pioneers of telecommunication") = Technikatörténeti Szemle 1973/74, VII.
p. 91.
- See Zworykin's own article: "The
Iconoscope - A modern Version Of The Electric Eye" = Proceedings of the Institute of
Radio Engineers, January 1934.
- V.K. Zworykin U.S. Pat. 1,691,324/July
13, 1925 appl., issued Nov. 13, 1928. This patent specifies and claims the same device as
did the original 1923 application, but adapted to color transmission of the Piaget type.
Although here Zworykin describes a photoelectric layer deposited in the form of
"globules," for reasons detailed further on in the article, as in the system
described by Zworykin in 1923, neither the devices (storage electrodes, etc.) nor the
conditions (continuous electron flow, etc.) for storage technology were specified in 1925.
- Correspondence between K. Tihanyi and
Prof. F. Schröter, April 1940. (The author's property.)
- K. Tihanyi: Hungarian appl. T-3768/March
20, 1926; German appl. 424822/June 11, 1928; German appl. 482422/July 3, 1928; Hungarian
appl. 9780/1928; Fr. Pat. 676.546/June 11, 1929; Br. Pat. Spec. 313.456/June 11, 1929; Br.
Pat. Spec. 315.362/July 10, 1929; U.S. Pat. 2.133,123 and 2,158,259/June 10, 1929. The two
U.S. patents were asssigned to RCA. Contrary to custom, however, these patents, as applied
for by RCA after purchasing the Tihanyi patents, do not reflect the full scope of the 1928
convention patent. For a clear picture of what Tihanyi really invented, it is therefore
essential to examine Br. 313,453 (and Fr. Pat. 676.546 issued as early as November 1929,
as well as Br.315,362), which includes designs and solutions of the subsequently developed
image iconoscope, orthicon and super orthicon.
- See Tihanyi correspondence with F.
Schröter, V. Babits, and T. Kiss. With regard to the latter, apparently mention had been
made of the patents of H. J. Round and Pierre Henroteau (U.S. Pat. No. 1,759,594, conv.
date May 21, 1926, respective Br. Pat. No. 335,995/June 4, 1929). These patents were first
brought up by Schröter in 1937 as parallel suggestions for storage. However, as Tihanyi
points out in a letter, both patents were filed subsequent to his 1926 application,
and--although both proposals feature arrangements where the photoelectric surface is
exposed to the light form the picture during the scansion cycle through a simple
condensing action--their output is determined by the minute local capacity of the
photoelectric layer, due to the absence of a separate storage electrode. In addition, as
Tihanyi points out, neither plan featured cathode ray scanning but operated with
mechanical commutators, and neither ever served as a basis for a practical television
system. (The author's property.)
- P. Vajda: Nagy magyar feltalálók,
(Great Hungarian Inventors) Budapest 1958, p. 356.
P. Vajda: "Nagy Magyar Feltalálók." Exhibit guide, Budapest 1973, p. 3. The
title of the exhibit would translate to "Great Hungarian Inventors."
P. Vajda: "Újabb adatok a hiradástechnika magyar úttörőire vonatkozóan"
("New data regarding the Hungarian pioneers of telecommunication") =
Technikatörténeti Szemle 1973/74., VII., pp. 89-92.
P. Vajda: "Magyar Alkotók" - Creative Hungarians, Budapest 1975, pp. 64-65.
P. Vajda: "Creative Hungarians in Mathematics, Astronomy, Physics, Chemistry,
Technical Sciences and Industry" = Technikatörténeti Szemle 1979, XI., pp. 69-70.
- P. Vajda: Op. Cit. Exhibit guide to
"Great Hungarian Inventors," Budapest 1973. p. 3.
- F. S. Wagner: Hungarian Contributions
to World Civilization, De Kalb Pike 1979, pp. 68-69; A. Abramson: The History of
Television, 1880 to 1941, Jefferson, North Carolina, 1987, p. 119;
Elma G. Farnsworth: Distant Vision; Romance and Discovery on an Invisible Frontier,
Salt Lake City, Utah, 1989, pp. 157-158.
- P. Nipkow: German patent 301105/1884.
- A. A. Campbell Swinton: "Scientific
Progress and Prospects" = Nature. December 7, 1911, pp. 191-195.
- V. K. Zworykin: "The Iconoscope - A
Modern Version Of The Electric Eye" = Proceedings of the Institute of Radio
Engineers, January 1934, pp. 18 and 23.
- V. K. Zworykin: G. A. Morton: Television,
the Electronics of Image Transmission, N.Y., London 1940, pp. 228, 231. "The
basic similarity between this type of tube and the mechanical scanners is evident from the
description of its mode of operation".
- A. Abramson: Op.Cit. p. 286.
- K. Tihanyi: "Az elektromos
távolbavetítésről" ("About electric transmission")= Nemzeti Újság,
May 3, 1925, p. 23.
- The International Dictionary of Physics
and Electronics, N.Y. 1956, 1961, pp. 126, 183, 859-861, 863, 1028-1028, 1094-1095.
- The Concise Dictionary of Physics,
Oxford, 1985.
- A. Abramson: Op.Cit. p. 155.
- Though often cited, this patent has never
been properly evaluated, except possibly by Paul Vajda. It is now available in English
translation at the Smithsonian Institution's Division of Electricity and Modern Physics,
Washington, D.C.; the Museum of Science and Technology, Budapest; and the CHEE/IEEE
Archives, Rutgers University, New Brunswick, N.J.;.
- K. Tihanyi, letters from London, 1931.
Most likely, the reference is made to U.S. patent application, serial no. 377.261, filed
on July 10, 1929, as was Br. Pat. No. 315,362 with the same content, both with conv. date
July 10, 1928 (The author's property.)
- Letter dated March 3, 1927, from prof.
Emmerich Poeschl to Zoltán Magyary, Ministerial Counselor; notarized German translation.
(The author's property.)
- K. Tihanyi, diary notes, 1927. (The
author's property.)
- The first letter indicating RCA's interest, conveyed
simultaneously by Tihanyi's German and British patent attorneys is not dated, but judging
form the content must be from the end of July 1930. (The author's property.)
- K. Tihanyi: Br. Pat. 352,035/December 21,
1929 application, (conv. date December 16, 1929, Hungary), issued June 22, 1931. In an
article, entitled, "Etwas uber das Fernsehen," ("About television,")
written by Tihanyi and published in the journal: Funk und Fernseh Technik, Berlin,
(undated, but judging form reference to the invitation by the British Air Ministry to
London, probably in early 1930) Tihanyi describes his Aerial Torpedo as a device which
also possesses "eyes" with the help of which it "sees" and locks onto
moving targets deploying one of various weapons it carries for the target's destruction.
It should be noted that the patent describes television guidance through specially
constructed light and heat sensitive photocells for other types of weaponry, such as
tanks, bombs, etc. as well (The author's property.)
- Letter by Tihanyi to his family, January
1932. indicating telephone call received from Paris, from RCA's European manager. Based on
subsequent letters to Tihanyi, this meeting was followed by personal negotiation with
RCA's G.A. Morton later co-author of Zworykin on two articles and the above referenced
book.
- A. Abramson: Op.Cit. p. 122.
- As disclosed by Abramson, the name
"Kinescope" appears on U.S. Pat. 2,021,252, issued to French inventor P.E.
Chevallier and assigned to RCA. The author notes - though the logic of his statement
eludes the reader - that, in the course of the prosecution, "RCA went on to great
lengths to prove that Chevallier was the first to use electrostatic focus. Obviously, this
was to protect RCA's interest in the vital picture tube that had been developed by
Zworykin"! Studying the patents, one can conclude that while Zworykin also describes
this feature, he states that he does not quite understand how it works.
- V.K. Zworykin: U.S. Pat. 2,246,283,
assigned to Westinghouse.
- V.K. Zworykin: U.S. Pat. 2,157,048,
assigned to RCA. The fact that the previous filing of May 1, was assigned to Westinghouse
would indicate that Zworykin's relationship with RCA was finalized at some time falling
between these two dates.
- See U.S. Patent Office archival file re.
Zworykin's 2,246,283, June 8, 1936 letter form the examiner, respective archival file re.
2,157,048, October 17, 1931 letter from the examiner.
- J. H. Udelson: The Great Television
Race. A History of the American Television Industry, Alabama, 1982, p. 85.
- A. Abramson: Op. Cit. 1987, p. 167. See
also V. Babits: A távolbalátás technikája, Budapest, 1948, p. 89. Babits who
co-authored an article with Zworykin in 1934 probably had this information from Z.
himself.
- Occupying the second half of a patent
specification, "claims" delineate each feature of a patent application that the
inventor considers an innovation. "Claims" then have to be consistent with the
description contained in the specification.
- V.K. Zworykin: U.S. Pat.
2,021,907/November 13, 1931.
- Archival files, U.S. Patent and Trademark
Office, Washington, D.C., Zworykin's 2,021,907, Paper No. 15, letter from the examiner.
- A. Abramson: Op. Cit. p. 214.
- U.S. Patent and Trademark Office,
Official Gazette, Apr. 30, 1935, Class 21.
- Archival file, U.S. Patent and Trademark
Office, Washington, D.C., K. Tihanyi 2,158,259.
- Archival file, U.S. Patent and Trademark
Office, Washington, D.C., V.K. Zworykin 2,021,907.
- See Patent Interference No.64027,
Farnsworth v. Zworykin, transcript of Final hearing, April 24, 1934. This document shows
that the Zworykin team presented two different theories as to how the 1923 Zworykin device
operated, claiming the two concepts were essentially the same. Yet, the judge, apparently
not persuaded by the testimonies or the introduced evidence, declared that the witnesses
described "two entirely different inventions," the first operation
being "entirely different from that now alleged...and which is necessary to produce
the electric charge image". This operation, of course, was described by Tihanyi in
1926 and 1929.
Table of Contents
TIHANYI GLASS KATALIN:
AZ IKONOSZKÓP: TIHANYI KÁLMÁN ALKOTÓ SZEREPE A TELEVÍZIÓ
MEGVALÓSULÁSÁBAN
Ismeretes az, hogy az ikonoszkópot, vagyis
a töltéstárolás elvén működő televíziót az irodalom az 1930-as évek óta szinte
egyhangúan V. K. Zworykin találmányaként tartotta számon.
Az 1970-es évek elején azonban Dr. Vajda
Pál történész, a korabeli találmányok beható tanulmányozása után, szembeszállva
az akkor már negyven éve terjesztett mítosszal megállapította, hogy a megoldás,
amely forradalmasította a televízió technológiáját és lehetővé tette annak
kivirágzását, nem V. K. Zworykin, hanem Tihanyi Kálmán találmánya volt. Vajda
továbbá rámutatott, hogy Zworykin az amerikai Radio Corporation által megvásárolt
Tihanyi szabadalmak alapján fejlesztette ki az ikonoszkópot a harmincas évek elején.
Tihanyi Kálmán érdemeinek
újraértékelése később Amerikában folytatódott, ahol az általában elfogadott
Zworykin mítoszt több oldalról megkérdőjelezték. Egyúttal évtizedekig tartó
agyonhallgatás után a magyar feltaláló neve felmerült az újabb keletű amerikai
technikatörténeti munkákban. Ezek már elismerik, hogy az ikonoszkópot jellemző
technológiára Zworykin nem 1923-ban, hanem csupán 1931 novemberi bejelentésében utalt
először, jóval Tihanyi szabadalmainak publikálása után és a magyar feltaláló és
a Radio Corporation közötti tárgyalások megkezdését követően.
A tanulmány szabadalmi levéltárban
őrzött akták, valamint egyéb eddig elhanyagolt, vagy hozzáférhetetlen elsődleges
forrás alapján vizsgálja az ikonoszkópnak, mint technológiának lényegét és ad
számot fejlesztésének eddig ismeretlen részleteiről.
Az angol nyelvű cikk
Table of Contents
Tihanyi in the technical
literature / Tihanyi a szakirodalomban
last update / utolsó frissítés: May 21,
2007
Tihanyi, Kálmán: "Az elektromos
távolbavetítésről", Nemzeti Újság, Science column, May 3, 1925, p. 23.
Tihanyi, Kálmán: "Etwas über das
Fernsehen, Die zukunft liegt im Kathodenstrahlapparat", most likely Funkstunde,
1929.
Editorial: "Unwarscheinliche
Fernsehfrotschritte", Funkbastler, Heft 7, 1930, p. 108
Schröter, Fritz: Handbuch der
Bildtelegraphie und des Fernsehens, Berlin: Julius Springer, 1932, pp. 61-65, 460.
Schröter, Fritz: Fernsehen, Die neue
Entwicklungen insbesondere der deutschen Fernsehtechnik, Berlin: Julius Springer, 1937,
pp. 50-51, 123.
Behne, R.: "Die Entwicklung der
Speicherröhre." In: 10 Jahre Fernseh A.G. Hausmitteilungen aus Forschung und
Betrieb der Fernseh Akziengesellschaft, Berlin, 1 Band, Heft 4, Juli 1939, 134-138.
Babits, Viktor: A távolbalátás és az
ultrarövid hullámok technikája, Budapest: Mérnöki Továbbképző Intézet
Kiadványai, VI., 3., 1942, pp. 11, 56, 65, 67, 100.
Tarján, Ferenc: Feltalálók
műhelytitkai, Budapest: Beta, 1943, 202-203.
Babits, Viktor: A távolbalátás
technikája, Budapest: Hungária, 1947, pp. 19, 48, 76, 89, 91, 147.
Below, F.: "Zur Entwicklung des
Fernsehens in Deutschland", FTZ, Heft 8, August 1950, p. 301
Goebel, Gerhard: Das Fernsehen in
Deutschland bis zum Jahre 1945, Archiv für das Post- und Fernmeldewesen Nr. 5.,
Frankfurt (Main), August 1953, 290-295, 388.
Vajda, Pál: Nagy magyar feltalálók,
Budapest: Zrinyi Kiadó, 1958, pp. 356, 359.
Bruch, Walter: Kleine Geschichte des
deutschen Fernsehens, Berlin: Hande & Spender, 1967, 38-39.
Vajda, Pál: "Újabb adatok a
hiradástechnika magyar úttörőire vonatkozóan", Technikatörténeti Szemle
VII (1973/74): 81-100.
Vajda, Pál: Magyar Alkotók - Creative
Hungarians, Budapest: Novex, 1975.
Wagner, Francis S.: Hungarian
Contributions to World Civilization, De Kalb Pike: Alpha Publications, 1977, 68-69.
Vajda, Pál: "Creative Hungarians in
Mathematics, Astronomy, Physics, Chemistry, Technical Sciences and Industry", Technikatörténeti
Szemle XI. (1979): 35-74.
Nagy, Ferenc és Nagy, Dénes, editors: Magyarok
a Természettudomány és Technika Történetében, Budapest: OMIKK, 1986, 1992, 1995.
Abramson, Albert: The History of
Television, 1880 to 1941, Jefferson: McFarland, 1986, pp. 119, 121, 155, 163, 167,
173, 215.
Farnsworth, Elma G.: Distant Vision.
Romance and Discovery on an Invisible Frontier, Salt Lake City: Pemberlykent
Publishers, Inc., 1989, p. 153.
Tihanyi Glass, Katalin: "The
Iconoscope: Kalman Tihanyi and the Development of Modern Television", Technikatörténeti
Szemle XX (1993): 173-199.
Abramson, Albert: Zworykin. Pioneer of
Television, University of Illinois Press, Campaign, 1995.
Shiers, George and May: Early
Television. A Bibliographic Guide to 1940, Garland Publishing, Inc., New York and
London, 1997, pp. 149, 152, 503.
Gazda, István: Magyar
Tudománytörténet, Piliscsaba: Magyar Tudománytörténeti Intézet, 1997, p. 188.
Nagy, Ferenc, ed.: Magyar Tudós
Lexikon, Budapest: OMIKK, 1997, 810-811.
Kádár, Márta: "Látogatás egy
kiállításon", Élet és Tudomány, LII. évf. 30. szám, July 25, 1977, p.
958.
Tihanyi, Katalin: "Az ikonoszkóp
magyar vonatkozása. Megemlékezés Tihanyi Kálmán életéről és
munkásságáról", the edited, illustrated version of the paper delivered at the
World Telecommunication Day Conference, Budapest, May 1997, Iparjogvédelmi Szemle
(Supplement to the Gazette of Patents and Trademarks, HPO) 102. évfolyam IV. szám,
August 1997, 42-47.
Vámos, Éva: "100 éve született
Tihanyi Kálmán", Technika, XL. évf. 9. szám, September 1997, 30-31.
Schatzkin, Paul: "The Farnsworth
Chronicles", www.farnovision.com/chronicles
(part 6 & 7).
Emmerson, Andrew: "Rewriting
History", Electronics World, November 1998, 925-926, www.bvws.org.uk/405alive/history/revisionist_history.html
Tetzner, Karl: "Entzauberte
Helden?" Funk Geschichte, 22. Jahrgang, Nr. 125, May/June 1999.
Bartolits, István: "A hiányzó
láncszem: a töltéstárolás elve" ; "A Tihanyi-féle ikonoszkóp";
"Szabadalmak egymás ellen", In: "A hírközlés története", article
series on the development of communication technology, Modern Kor, VI. évf. 4.,
5., 6. szám, May 2000, p. 23, June 2000, p. 18, July 2000, p. 10.
Tihanyi, Katalin: "A televízió nagy
magyar úttörője", Magyar Tudomány, 2000/6, 774-784. www.scitech.mtesz.hu
Tihanyi, Katalin: "Tihanyiról,
Zworykinról és a szekunder elektronokról. Hozzászólás a Bay Zoltán munkásságával
foglalkozó cikkhez," Magyar Tudomány 2001/1, 102-103.
Kovács, László: " Válasz Tihanyi
Katalinnak", Magyar Tudomány 2001/1, p. 103.
Sipka, László: "Innovators and
innovations", The Hungarian Quarterly, Vol. 42., Summer 2001, 20-34.
Jeszenszky, Sandor: "A televízió
magyar fejlesztői. Mihály Dénes és Tihanyi Kálmán" In: Több nemzet vallja
magáénak, Ed: Walter Endrei and Sandor Jeszenszky, Budapest: Balassi Kiadó, 2001,
131-136.
Tihanyi Glass, Katalin: "Hetvenéves a
modern televízió. A Radioszkóp", Élet és Tudomány, Vol. LVI., No. 39,
September 28, 2001, 1225-1230.
Editorial: "Magyar feltaláló a
Világmemóriában" Magyar Tudomány, 2001/11, p. 1371.
"Tihanyi Kálmán (1897-1947).
Korszakváltás a televízió történetében" In: Álmok Álmodói
Világraszóló Magyarok, Exhibit Catalogue, Vol. I. Budapest: Millenaris Kht., 2002,
204-221.
Abramson, Albert: Die Geschichte des
Fernsehens, Munich: Fink Verlag, 2003.
Horváth, Gyula: "EMC kompatibilis
lapos képcső -- anno 1936!", Híradástechnika, Volume LIX, January 2004,
52-56; www.scitech.mtesz.hu
Bödők, Zsigmond: "Tihanyi
Kálmán", In: Magyar feltalálók a távközlés történetében, Dunaszerdahely:
NAP Kiadó, 2005, 109-119.
"Kalman Tihanyi" in "Thinkers through the
Ages" and "Inventors/Scientists", www.iec.ch/100years/techline
, 2006.
Bödők, Zsigmond: "Kalman Tihanyi" in: Magyar
feltalálók a hírközlés történetében, Dunaszerdahely: NAP Kiadó, 2006, 262-271
Table of Contents |
