What is Electron gun: Definition and 29 Discussions

An electron gun (also called electron emitter) is an electrical component in some vacuum tubes that produces a narrow, collimated electron beam that has a precise kinetic energy. The largest use is in cathode ray tubes (CRTs), used in nearly all television sets, computer displays and oscilloscopes that are not flat-panel displays. They are also used in field emission displays (FEDs), which are essentially flat-panel displays made out of rows of extremely small cathode ray tubes. They are also used in microwave linear beam vacuum tubes such as klystrons, inductive output tubes, travelling wave tubes, and gyrotrons, as well as in scientific instruments such as electron microscopes and particle accelerators.
Electron guns may be classified by the type of electric field generation (DC or RF), by emission mechanism (thermionic, photocathode, cold emission, plasmas source), by focusing (pure electrostatic or with magnetic fields), or by the number of electrodes.

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  1. S

    Electrical Need advice on building a linear particle accelerator

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  2. C

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    For part (a) of this problem, The solution is, However, why did they need to take the absolute value of the charge? I thought they could keep the original signs as shown below: Using energy conservation, the electric force dose internal work transferring electric potential energy into...
  3. rsc9421

    A Power consumed by electron gun

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  4. D

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  5. SWKatzen

    Exploring Electron Gun Deflection: Causes and Resources for Understanding

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  6. D

    Electron gun in a vacuum -- How hard of a vacuum is needed?

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  7. chucrut

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  8. R

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  9. J

    B Electron Gun for a Grade 9 Physics Project?

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  10. dholbach

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  11. O

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  12. P

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  13. D

    Can a electron gun attract/repel permanent magnet?

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  14. genxium

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  15. S

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  16. T

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  17. I

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  18. J

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  19. P

    How to Remove Electron Gun from CRT?

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  20. M

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  21. C

    How would the electric field look like for an electron gun?

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  22. E

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  23. C

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  24. S

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  25. D

    What angle should an elctron beam leave an electron gun?

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  26. S

    Calculating the electric field in an electron gun

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  27. M

    Electron Gun Grounding: Best Practices for Photoemission Experiments

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  28. F

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  29. C

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