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A scheme for focusing sheet, beams by means of a periodic configuration of magnetic fields directed transverse to the beam is presented. Discussion of a particular model gives information about stability limits and perveance. This scheme, which lends itself to the incorporation of intense magnetic fields, should be immune to the space-charge instabilities of beams focused in longitudinal magnetic fields. The focusing mechanism is such as to produce coupling between the beam and electromagnetic waves of phase velocity exceeding the velocity of light. Application to millimetre-wave tubes is anticipated.
Wiki User
∙ 12y ago
Wiki User
∙ 13y agoA: ON an CRT emitted electrons must be focused to a spot to see the detail of the information. There are purity rings on a CRT that does exactly that by magnetism the electrons are focused.
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What is called the winding around the CRT yoke that deflects the electron beam with its magnetic field?
It's called a deflection coil. If a c.r.t. uses magnetic deflection, there will be two deflection coils, a horizontal one and a vertical one.
Define the deflection sensitivity of CRT?
There is basically two cases: (It is recommended to read about Cathode Ray Tube Deflection prior to read this) 1 - Electrostatic Deflection: Is the voltage necessary to move the electronic beam by a unit of lenght. Usually is V/cm or V/in. Since there is no significant current flowing on the deflection plates, and these kind of CRTs (Cathode Ray Tubes) are using on measuring devices (on wich the lenght of the trace on the screen will be measured in a way or another), only the voltage is relevant on the specification of the CRT, and its effect on the moving of the bean. CRT manufacturers made a tremendous effort to make the relationship between the Voltage on the plates and the beam deflection to be linear. 2 - Magnetic Deflection: Used on most popular CRTs, as TVs, Monitors (now being replaced by LCDs). Is the product of the square of the total (Ap-p)current needed to deflect the beam tottaly on the screen (from left to right - horizontal deflection, or top to bottom - vertical deflection), and the inductance of the coil. It is understood as the minimum energy that the inductor (the deflection coil) must store to generate the magnetic field and move the beam totally on the screen. Magnetic is the most complicated deflection since there are several factor affecting the performance of the circuit, i.e. coil resistance, geometric limitations, core saturation, variation of core permeability. Is the product of the inductance of the coil by the peak-to-peak current, squared. Most of the time is given in mHApp^2, but less often found in OhmsApp^2 Needless to say that the CRT using this kind of deflection uses several types of correction of linearity, because now the beam does no move in a linear way with the surface of the screen. The most popular are East-West correction, Pin-Cushion correction, and S-correction. There is basically two cases: (It is recommended to read about Cathode Ray Tube Deflection prior to read this) 1 - Electrostatic Deflection: Is the voltage necessary to move the electronic beam by a unit of lenght. Usually is V/cm or V/in. Since there is no significant current flowing on the deflection plates, and these kind of CRTs (Cathode Ray Tubes) are using on measuring devices (on wich the lenght of the trace on the screen will be measured in a way or another), only the voltage is relevant on the specification of the CRT, and its effect on the moving of the bean. CRT manufacturers made a tremendous effort to make the relationship between the Voltage on the plates and the beam deflection to be linear. 2 - Magnetic Deflection: Used on most popular CRTs, as TVs Monitors (now being replaced by LCDs). Is the product of the square of the total (Ap-p)current needed to deflect the beam tottaly on the screen (from left to right - horizontal deflection, or top to bottom - vertical deflection), and the inductance of the coil. It is understood as the minimum energy that the inductor (the deflection coil) must store to generate the magnetic field and move the beam totally on the screen. Magnetic is the most complicated deflection since there are several factor affecting the performance of the circuit, i.e. coil resistance, geometric limitations, core saturation, variation of core permeability. Is the product of the inductance of the coil by the peak-to-peak current, squared. Most of the time is given in mHApp^2, but less often found in OhmsApp^2 Needless to say that the CRT using this kind of deflection uses several types of correction of linearity, because now the beam does no move in a linear way with the surface of the screen.
What is horizontal deflection?
The term horizontal deflection refers to how much something deviates from the horizontal line.
What is vertical deflection plate?
As we mentioned earlier, a CRT can be used to graphically and visually plot an electronic signal,such as a sine wave. This is done by using a second set of deflection plates called VERTICAL-DEFLECTION PLATES
What is full scale deflection?
Full Scale Deflection is equal to the max value on a scale or meter. If a thermometer reads from -20 degrees to +100 degrees, the full scale deflection = 100 degrees and the range = 120 degrees
What meant by magnetic focusing and how does a momentum selector work?
1800 magnetic deflection is mainly used in mass spectrograph for separating the different types of ions or for focusing the charged particles of same momentum on the screen nearly at the same point when they enter through the slit at different angles. Hence it is also known as 1800 magnetic focusing or momentum selector. When a beam of charged particles enters through a slit in a uniform magnetic field B in direction perpendicular to the direction of field with a velocity v the particles move in a circular path the radius of which is r=mv/qB. Thus a beam of particles of same momentum mv can be obtained after 1800 deflection .
What is called the winding around the CRT yoke that deflects the electron beam with its magnetic field?
It's called a deflection coil. If a c.r.t. uses magnetic deflection, there will be two deflection coils, a horizontal one and a vertical one.
How do you compare magnetic moments of two magnets using deflection magnetometer?
introduce it in magnetic field.
What is magnetic deflection sensitivity of CRO?
ghanta le lo
What is magnetic deflection senstivity?
Magnetic deflection sensitivity of a cathode ray oscilloscope (CRO) is defined as the amount of deflection of electron spot produced when a magnetic flux density of 1 Wb/m2 is applied. SM = (e / m )1\2 x 1\ (2V0) 1\2 x l x L
What is an electrical current that produces a magnetic field?
The deflection of a magnetic compass in the presence of an electric current, is evidence that an electric current produces a magnetic field.
What is evidence that an electrical current produces a magnetic field?
The deflection of a magnetic compass in the presence of an electric current, is evidence that an electric current produces a magnetic field.
Does a lodestone create a magnetic field?
A lodestone is magnetized and thus produces a magnetic field around it. This can be detected by the deflection of a compass needle.
Why deflection of the magnetic needle placed in a coil carrying current increases as the number of turns in the coil increases?
Deflection of the magnetic needle placed in a coil carrying current increases as the number of turns in the coil increase because as the number of turns in the coil increases the strength of the magnetic field also increases.
What is hall effect explain briefiy?
Deflection of moving carriers in a semiconductor perpendicular to a magnetic field.
What are the main parts of CRO?
1. Electron Gun 2. Focusing system 3. Deflection system 4. Fluorescent screen
What did Thomson use in his experiments?
J.J. Thomson studied the deflection of cathode rays in electric and magnetic fields.
