Search results
Results From The WOW.Com Content Network
The current in a beam of cathode rays through a vacuum tube can be controlled by passing it through a metal screen of wires (a grid) between cathode and anode, to which a small negative voltage is applied. The electric field of the wires deflects some of the electrons, preventing them from reaching the anode.
In vacuum tubes (including cathode-ray tubes) it is the negative terminal where electrons enter the device from the external circuit and proceed into the tube's near-vacuum, constituting a positive current flowing out of the device.
The first commercially made electronic TV sets with cathode-ray tubes were manufactured by Telefunken in Germany in 1934. [32] [33] In 1947, the cathode-ray tube amusement device, the earliest known interactive electronic game as well as the first to incorporate a cathode-ray tube screen, was created. [34]
The cathode-ray tube by which J. J. Thomson demonstrated that cathode rays could be deflected by a magnetic field, and that their negative charge was not a separate phenomenon While supporters of the aetherial theory accepted the possibility that negatively charged particles are produced in Crookes tubes , [ citation needed ] they believed that ...
The control grid is an electrode used in amplifying thermionic valves (vacuum tubes) such as the triode, tetrode and pentode, used to control the flow of electrons from the cathode to the anode (plate) electrode. The control grid usually consists of a cylindrical screen or helix of fine wire surrounding the cathode, and is surrounded in turn by ...
In general, an X-ray's beam intensity is not uniform. When it focuses to a target, a conical shape appears (divergent beam). The intensity of the beam from the positive anode side is lower than the intensity from the negative cathode side because the photons created when the electrons strike the target have a longer way to travel through the rotating target on the anode side.
The cathode is the negative electrode. Any gas-discharge lamp has a positive (anode) and a negative electrode. Both electrodes alternate between acting as an anode and a cathode when these devices run with alternating current. A standard computer case fitted with blue and green cold-cathode tubes Cold-cathode fluorescent lamp backlight
A modern dental X-ray tube. The heated cathode is on the left. Centre is the anode which is made from tungsten and embedded in the copper sleeve. William Coolidge explains medical imaging and X-rays. An X-ray tube is a vacuum tube that converts electrical input power into X-rays. [1]