Normal glass isn't particularly luminescent so tubes designed to produce light (like a CRT) are coated with phosphors. Basically, the electrons striking the glass excite components of the glass to an elevated electronic state which releases light upon returning to the ground state. A potential placed between the cathode and the anode accelerates these electrons through the tube, at the front face of which they strike a phosphor screen. Each stream travels through a shadow mask where the electrons will impinge upon either a red, green or blue phosphor to light up a color pixel on the screen.
A filament near the cathode heats it, boiling electrons off it. 60 An electron in a cathode-ray tube is accelerated thr. Most color cathode-ray tubes incorporate three electron guns, each one producing a different stream of electrons. The glow of the glass envelope is luminescence-either fluorescence or phosphorescence (or both). A cathode ray tube is an evacuated glass envelope having a cathode at the back, and an anode some distance in front of it. In cold cathodes, electrons are released by field emission, where a large applied electric field allows electrons to tunnel away from a metal electrode. The electron beam is produced by thermionic emission in hot cathodes-electrons are liberated from a hot filament when the thermal energy is enough for electrons to exceed the filament's work function. It is an additional object of the present invention to provide a method for reducing the number of residual gas molecules in a cathode-ray tube to a greater. If there's enough gas, you get a plasma rather than a beam of electrons. The vacuum doesn't have much to do with the production of electrons, per se, but without high vacuum, the electrons collide with gas particles before they travel very far. When the two metal plates are connected to a highvoltage source, the negatively charged plate. The sharp shadows produced by Crookes tubes meant that something was travelling in a straight line from the cathode down the tube, so they were named cathode rays. power strips jumper cables with banana plugs to connect everything a fairly powerful magnet Procedure Deflection of Cathode Rays (electron beam) by an Electric Field - Turn on the power strip. It is a glass tube from which most of the air has been evacuated.
The name exists because cathode ray devices predate the discovery of the electron. "Cathode rays" are simply beams of electrons. A cathode ray is defined as a stream of electrons leaving the negative electrode (or cathode) in a discharge tube that contains gas at low pressure or the electrons emitted by the heated filament in certain electron tubes.
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