Karl Ferdinand Braun
1850-1918
1850-1918
The Cathode Ray Tube site
electronic glassware
History and Physics Instruments
electronic glassware
History and Physics Instruments
The Braun tube, this small early 1900 tube is in fact a cold Cathode Crookes tube with an internal mica screen covered with phosphorescent paint. The neck contains a glass diaphragm with a small 2mm hole to let only a tiny electron beam go through (focus) which can be deflected by an (electro) magnet to produce a spot on the screen. Click here to see the family of educational CRT's sold by Max Kohl early 1900 and here by Müller-Uri.
Thomsons experimental tube
Click at the picture to see the original tube in The Cavendish Lab at the University of Cambridge.
Click at the picture to see the original tube in The Cavendish Lab at the University of Cambridge.
The beginning of the CRT Century which would last more than 100 Years!
In Europe there were several companies active with the early CRT techniques like,
Leybold & Von Ardenne, Emil Gundelach, Philips, Lorenz AG, Telefunken AG, Otto Pressler,
Gladitz GmbH, Fernseh AG, Radio AG, D.S.Loewe, Baird Television, Marconi-EMI and Cossor.
Some of them were close connected to RCA or the Farnsworth company. Most of these firms
had also long reputation in early science vacuum tube technology.
In the US General Electric, The Bell laboratories, National Union, Westinghouse, RCA Victor,
Farnsworth Television, and Dumont developed their pre-War CRT's.
The first used CRT's were the low pressure argon filled tubes. In these low vacuum tubes the
focus of the beam was regulated by controlling the heater current like the Western 224.
The first US commercial available high vacuum CRT developed by Zworykin, at that time working
for Westinghouse (part of RCA) was the high vacuum RCA 906.
Vladimir Kosma Zworykin demonstrated this tube in the first RCA TV receiver in 1929 and named
the CRT Kinescope, it was used with 60 lines at 12 frames per second. Zworykin played an
important role in the electronic TV development, he eventual became director of RCA, in those
days the leading CRT producing company in the US. RCA made large progress in developing
different and better tubes for TV, radar and oscilloscopes.
Farnsworth television also produced for a short period low vacuum tubes for his television
receivers, this CRT's were called Oscillite which never became successful like the RCA tubes.
Another important player on the US CRT market was Allen B Dumont who developed his
own CRT's and started CRT production in 1931 in his garage mainly for oscilloscopes,
later also for Television. There were tubes produced by DuMont with only one deflection plate,
this could be done by placing the gun under an angle pointing towards the side of the tube.
For TV use, magnetically deflecting won over statically deflection due to the high tensions needed
in the deflection amplifier circuits for tubes with large screen sizes.
In Japan Kenjiro Takayanagi at the Hamamatsu Higher Technical Institute worked on CRT
television since 1924. He started the production of high vacuum CRT's in 1930 build by
Dr. Asao at the research Institute of Tokyo Shibura Electric Company. The early CRT displays
were used with 40 lines flyingspot scan techniques, the camera tubes were not yet developed.
In 1936 he presented a 30 Hz 245 lines interlaced all electronic television system. Going further
in 1937 to 441 lines competing with the rest of the world, in 1939 Nippon Electric Company
produced the first domestic TV sets for the Japanese market.
In Europe there were several companies active with the early CRT techniques like,
Leybold & Von Ardenne, Emil Gundelach, Philips, Lorenz AG, Telefunken AG, Otto Pressler,
Gladitz GmbH, Fernseh AG, Radio AG, D.S.Loewe, Baird Television, Marconi-EMI and Cossor.
Some of them were close connected to RCA or the Farnsworth company. Most of these firms
had also long reputation in early science vacuum tube technology.
In the US General Electric, The Bell laboratories, National Union, Westinghouse, RCA Victor,
Farnsworth Television, and Dumont developed their pre-War CRT's.
The first used CRT's were the low pressure argon filled tubes. In these low vacuum tubes the
focus of the beam was regulated by controlling the heater current like the Western 224.
The first US commercial available high vacuum CRT developed by Zworykin, at that time working
for Westinghouse (part of RCA) was the high vacuum RCA 906.
Vladimir Kosma Zworykin demonstrated this tube in the first RCA TV receiver in 1929 and named
the CRT Kinescope, it was used with 60 lines at 12 frames per second. Zworykin played an
important role in the electronic TV development, he eventual became director of RCA, in those
days the leading CRT producing company in the US. RCA made large progress in developing
different and better tubes for TV, radar and oscilloscopes.
Farnsworth television also produced for a short period low vacuum tubes for his television
receivers, this CRT's were called Oscillite which never became successful like the RCA tubes.
Another important player on the US CRT market was Allen B Dumont who developed his
own CRT's and started CRT production in 1931 in his garage mainly for oscilloscopes,
later also for Television. There were tubes produced by DuMont with only one deflection plate,
this could be done by placing the gun under an angle pointing towards the side of the tube.
For TV use, magnetically deflecting won over statically deflection due to the high tensions needed
in the deflection amplifier circuits for tubes with large screen sizes.
In Japan Kenjiro Takayanagi at the Hamamatsu Higher Technical Institute worked on CRT
television since 1924. He started the production of high vacuum CRT's in 1930 build by
Dr. Asao at the research Institute of Tokyo Shibura Electric Company. The early CRT displays
were used with 40 lines flyingspot scan techniques, the camera tubes were not yet developed.
In 1936 he presented a 30 Hz 245 lines interlaced all electronic television system. Going further
in 1937 to 441 lines competing with the rest of the world, in 1939 Nippon Electric Company
produced the first domestic TV sets for the Japanese market.
With the increasing TV market, mass production of CRT's was the result.
These pictures above are from the Philips tube factory about 1947.
These pictures above are from the Philips tube factory about 1947.
Philips TV projection tube [1]
This tube with a hollow face to prevented picture distortion on a 40 x50 cm screen.
This tube with a hollow face to prevented picture distortion on a 40 x50 cm screen.
Philips DW31-2 CRT [6]
This is a 31cm TV tube from 1937.
DW means double electrostatic deflection.
MW means magnetic deflection.
SW means only one pair of electrostatic deflection plates, this can be used
together with magnetic deflection.
The W stands for white phosphor.
This is a 31cm TV tube from 1937.
DW means double electrostatic deflection.
MW means magnetic deflection.
SW means only one pair of electrostatic deflection plates, this can be used
together with magnetic deflection.
The W stands for white phosphor.
Philips TV projection CRT 1949 [1]
Due to distortion problems with bigger tubes Philips developed small projection CRT's.
Due to distortion problems with bigger tubes Philips developed small projection CRT's.
Early Ediswan CRT [1]
This is one of the first known Ediswan CRT's.
With screw connections on the base.
This is one of the first known Ediswan CRT's.
With screw connections on the base.
No, it's not me ! [6]
It's actually a 50cm Telefunken CRT from 1938 with a total length of 85 cm, these were used in mirror TV's.
It's actually a 50cm Telefunken CRT from 1938 with a total length of 85 cm, these were used in mirror TV's.
HOME
NEXT
Joseph John Thomson (1856-1940), professor of Physics
at the Cambridge University, proved in 1897 that Cathode
rays were streams of particles (corpuscles) that carried a
negative charge and were 2000 times lighter than the
hydrogen atom and called electrons. He used his new
developed CRT to measure the mass to charge m/e ratio.
You can find a detailed description here at the University of
Canberra. Thomson's work has been a great contribution in
the development of Cathode Ray tubes. A complete
description of Thomson can be found at the
American Institute of Physics.
Including audio recordings of him about his discovery,
definitely a must see website for anyone interested.
JJ Thomson developed his tube slightly earlier than Braun's
tube and has two internal statically deflection plates
instead of the magnetic deflection Braun used in his early
experiments. Although Thomsons type of deflection is
used in many CRT designs, the common name in most
European country's is still Braun tube.
at the Cambridge University, proved in 1897 that Cathode
rays were streams of particles (corpuscles) that carried a
negative charge and were 2000 times lighter than the
hydrogen atom and called electrons. He used his new
developed CRT to measure the mass to charge m/e ratio.
You can find a detailed description here at the University of
Canberra. Thomson's work has been a great contribution in
the development of Cathode Ray tubes. A complete
description of Thomson can be found at the
American Institute of Physics.
Including audio recordings of him about his discovery,
definitely a must see website for anyone interested.
JJ Thomson developed his tube slightly earlier than Braun's
tube and has two internal statically deflection plates
instead of the magnetic deflection Braun used in his early
experiments. Although Thomsons type of deflection is
used in many CRT designs, the common name in most
European country's is still Braun tube.
J.J. Thomson in the Cavendish Lab
Cathode Ray Tubes
From the beginning to the end....
From the beginning to the end....
Want to know CRT basics ? Look here at Wikipedia.
You can find much tube data at Frank's Electron tube Pages.
You can find much tube data at Frank's Electron tube Pages.
Annalen der
Physik und Chemie
F. Braun 1897
See here the translation of the
original German publication from
Ferdinand Braun concerning
his work on the Braun tube.
Physik und Chemie
F. Braun 1897
See here the translation of the
original German publication from
Ferdinand Braun concerning
his work on the Braun tube.
THE EARLY DAYS OF THE CRT
Allen Balcom DuMont
1901 - 1965
1901 - 1965
Manfred von Ardenne
1907 - 1997 [1]
1907 - 1997 [1]
Didactic
CRT's
CRT's
Scope
CRT's
CRT's
Radar
CRT's
CRT's
TV
CRT's
CRT's
Misc.
CRT's
CRT's
Look at the collection of different CRT's on the next pages.
Braun tube after Thomson, second quarter 20th Century. Length 65cm.
This from origin cold cathode Braun tube is equipped with two deflection plates to bent the beam electrostatic instead of the magnetically deflected Braun tube.
This tube became forerunner of the static CRT used in measuring equipment like the oscilloscope. The neck contains an aluminum diaphragm to form the beam.
This from origin cold cathode Braun tube is equipped with two deflection plates to bent the beam electrostatic instead of the magnetically deflected Braun tube.
This tube became forerunner of the static CRT used in measuring equipment like the oscilloscope. The neck contains an aluminum diaphragm to form the beam.
Deflection section
The phosphor mica screen.
The first lines appear on the screens in this type of early tubes in order to measure the amount of voltage supplied
to the deflection plates in respect to the
deviation of the beam. In later tubes the glass front is internally covered with phosphor like in modern CRT's.
The first lines appear on the screens in this type of early tubes in order to measure the amount of voltage supplied
to the deflection plates in respect to the
deviation of the beam. In later tubes the glass front is internally covered with phosphor like in modern CRT's.
Collection of Radio-AG D.S Loewe CRT's 1937.
These are high vacuum tubes. [6]
These are high vacuum tubes. [6]
Two Lorenz CRT's 1937. [6]
Electrostatic deflection for projection use.
Electrostatic deflection for projection use.
Vladimir Kosma Zworykin
1889-1982
1889-1982
Click on the pictures for the original German documentation from Gundelach and information about the Fernseh AG Company.
From this fine web site.
Foundation for German communication and related technologies.
From this fine web site.
Foundation for German communication and related technologies.
Early RCA TV ad
Karl Ferdinand Braun a German physicist, interested in the just discovered Cathode rays worked and experimented with Crookes tubes. When he was working at the Physics Institute of the Strasbourg University (from 1895-1918) he developed the first cold Cathode Ray tube with magnetically beam deflection (the effect discovered by Plucker and Hittorf in 1869) and a mica screen covered with phosphor to produce a visible spot. The tube, build for him by Franz Müller successor of Geissler was called after its inventor, the Braun tube. Braun used this tube as an indicator tube for studying the effects of Cathode rays in order to visualize alternating currents and described this 1897, this was in fact the first oscilloscope. Harris J Ryan introduced this tube in 1903 in the USA as an alternating current wave indicator, known as the Braun-Ryan tube.
The first ideas of using Cathode rays (Braun's tube) for Television came from the Englishman Campbell Swinton in 1908. The Frenchman Rignoux and the Russian Rosing experimented also with the Braun's tube for the same reason, just like Belin and Holweck who used Cathode rays for their TV receiver and demonstrated it in Malmaison in 1928. At that time, mechanical TV was the only way to transmit moving images, mostly with a Baird, TeKaDe, or Jenkins (US) mechanical receiver.
The first ideas of using Cathode rays (Braun's tube) for Television came from the Englishman Campbell Swinton in 1908. The Frenchman Rignoux and the Russian Rosing experimented also with the Braun's tube for the same reason, just like Belin and Holweck who used Cathode rays for their TV receiver and demonstrated it in Malmaison in 1928. At that time, mechanical TV was the only way to transmit moving images, mostly with a Baird, TeKaDe, or Jenkins (US) mechanical receiver.
Television before and during the War.
From the 1930's on, electronic TV developments started in Europe and the US, many companies produced series of electronic TV sets more than 25.000 sets were produced in the US when the War stopped the production. From 1935 the developments in Germany were under strict orders from the Nazi regime, in march of that same year the Fernsehgruppe Paul-Nipkow started their first TV Broadcasting with the Von Ardenne mechanical camera system using film, and later also with Iconoscope camera's at the Olympic Games in 1936, using techniques with permission from RCA and Farnsworth Television. Companies like Loewe AG and Lorenz AG were held under rigorous military control and Von Ardenne joined like many other German scientists the Nazi regime. From 1939 the TV manufacturing in Germany stopped completely due to the beginning of the War. German Nazi Television, only limited to Berlin for fifty high placed persons and a few public TV places called Fernsehstubes for the propaganda TV. In 1943 after bombings on Berlin the survived TV equipment went to occupied France where the Germans build a new TV studio in Paris at
180 Rue de l'Université with the name "Magic City". It was completely build by Telefunken A.E.G and Fernseh AG, and was used until August 16 1943 when they took
all equipment back to Germany. Look here for an interesting Dutch television documentary about recently found (1999) original Nazi film-for-TV footage.
In Britain first public TV BBC Broadcasting started in London 1933 in the Crystal Palace facility, Europe's largest TV studio's, home of the Baird television company using mechanical camera's, although the Baird company had connections with Farnsworth, their Dissector pickup tube was not used due to it's poor light sensitivity.
The Crystal Palace burned to the ground in 1936 but Baird's CRT production plant housed in the same building was spared. After the fire the BBC banned Baird's mechanical camera system and was replaced by the Marconi-EMI all electronic system. (EMI had license cross-connections with RCA)
During WWII, the TV production in the US and UK stopped almost complete, development of radar and oscilloscope techniques for the War industry had now more priority. You can find more info about early British television on these fine web sites Baird's Independent Television and Baird Television. See also the Camera tubes page.
From the 1930's on, electronic TV developments started in Europe and the US, many companies produced series of electronic TV sets more than 25.000 sets were produced in the US when the War stopped the production. From 1935 the developments in Germany were under strict orders from the Nazi regime, in march of that same year the Fernsehgruppe Paul-Nipkow started their first TV Broadcasting with the Von Ardenne mechanical camera system using film, and later also with Iconoscope camera's at the Olympic Games in 1936, using techniques with permission from RCA and Farnsworth Television. Companies like Loewe AG and Lorenz AG were held under rigorous military control and Von Ardenne joined like many other German scientists the Nazi regime. From 1939 the TV manufacturing in Germany stopped completely due to the beginning of the War. German Nazi Television, only limited to Berlin for fifty high placed persons and a few public TV places called Fernsehstubes for the propaganda TV. In 1943 after bombings on Berlin the survived TV equipment went to occupied France where the Germans build a new TV studio in Paris at
180 Rue de l'Université with the name "Magic City". It was completely build by Telefunken A.E.G and Fernseh AG, and was used until August 16 1943 when they took
all equipment back to Germany. Look here for an interesting Dutch television documentary about recently found (1999) original Nazi film-for-TV footage.
In Britain first public TV BBC Broadcasting started in London 1933 in the Crystal Palace facility, Europe's largest TV studio's, home of the Baird television company using mechanical camera's, although the Baird company had connections with Farnsworth, their Dissector pickup tube was not used due to it's poor light sensitivity.
The Crystal Palace burned to the ground in 1936 but Baird's CRT production plant housed in the same building was spared. After the fire the BBC banned Baird's mechanical camera system and was replaced by the Marconi-EMI all electronic system. (EMI had license cross-connections with RCA)
During WWII, the TV production in the US and UK stopped almost complete, development of radar and oscilloscope techniques for the War industry had now more priority. You can find more info about early British television on these fine web sites Baird's Independent Television and Baird Television. See also the Camera tubes page.
Didactic
CRT's
CRT's
Scope
CRT's
CRT's
Radar
CRT's
CRT's
TV
CRT's
CRT's
Misc.
CRT's
CRT's
The CRT History page
The first Braun tube model. [12]
In the first production of thirty tubes the screen was placed under an angle for better viewing.
In the first production of thirty tubes the screen was placed under an angle for better viewing.
[10]
[1]
[1]
A great 314 page book about CRT is:
The Cathode-Ray Tube
Technology, History, and Applications
By Peter A. Keller
$69.50 + $25 shipping worldwide
This can only be ordered by him personally.
e-mail: peterke1(at)comcast(dot)net
The Cathode-Ray Tube
Technology, History, and Applications
By Peter A. Keller
$69.50 + $25 shipping worldwide
This can only be ordered by him personally.
e-mail: peterke1(at)comcast(dot)net