1 / 11

Electron movement in CRT such as a TV screen

Electron movement in CRT such as a TV screen . Abdulaziz Abdulrahman Part One: Content (Research for information) Nawaf Abdullah Part three: Slide transitions and effects Pictures, Diagrams and Animated Figures Omar Part Two: Videos and Hyperlinks and some slide 12.05 , 12.06 .

sorena
Download Presentation

Electron movement in CRT such as a TV screen

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Electron movement in CRT such as a TV screen Abdulaziz Abdulrahman Part One: Content (Research for information) Nawaf Abdullah Part three: Slide transitions and effects Pictures, Diagrams and Animated Figures Omar Part Two: Videos and Hyperlinks and some slide 12.05 , 12.06

  2. Basic atomic structure • Atoms are made up of three main particles. These are the neutron, electron, and proton. These main parts are each made up of smaller particles. This picture shows the placement of each of the main particles. • The Proton is positively charged and is in the nucleus. The Neutron has no electrical charge and is in the the nucleus also.The electron moves around the nucleus and it has a negative charge.

  3. Types of Emission of electrons The fore type of: • Thermionic emission • Field emission • Photoelectric emission • Secondary emission

  4. Thermionic emission of electrons • is the heat-induced flow of charge carriers from a surface or over a potential-energy barrier. This occurs because the thermal energy given to the carrier overcomes the forces restraining it. The charge carriers can be electrons or ions, and in older literature are sometimes referred to as "thermions"

  5. History of CRT • The earliest version of the CRT was invented by the German physicist Ferdinand Braun in 1897 and is also known as the Braun tube. It was a cold-cathode diode a modification of the Crookes tube with a phosphor-coated screen. • In 1907, Russian scientist Boris Rosing used a CRT in the receiving end of an experimental video signal to form a picture. He managed to display simple geometric shapes onto the screen, which marked the first time that CRT technology was used for what is now known as TV.

  6. Construction and working of a CRT • The Cathode Ray Tube (CRT) is a vacuum tube containing an electron gun and a fluorescent screen, with internal or external means to accelerate and deflect the electron beam, used to create images in the form of light emitted from the fluorescent screen. The image may represent electrical waveforms (oscilloscope), pictures (television, computer monitor), radar targets and others.

  7. Movement of electrons in a CRT such as TV screen • a CRT’s electrons are concentrated into a tight beam by a positively charged terminal, called an anode. An accelerating anode is then used to speed up the movement of the electrons. These fast-moving electrons fly through the tube’s vacuum, hitting the phosphor-coated screen and making it glow.

  8. Movement of electrons in a CRT such as TV screen

  9. Advantages of CRT • Indeed, one of the most distinct advantages of CRT TVs over all other television displays is pricing. CRTs are far from being obsolete, but because of competition from other TV display technologies, prices per unit of CRT TVs are becoming more and more affordable.

  10. why CRT replaced by LCD? • THESE DAYS AN OVERWHELMING NUMBER of flat-panel LCD monitors are available, with each vendor offering multiple models. Though costs have dropped somewhat, they are not yet so low that these sophisticated displays are flying off vendors' shelves. • Response time for flat-panel displays has long been on the slow side, making them less than ideal for video use or for applications such as 3D CAD and visualization, where rotating a model or showing a walkthrough may result in a visual stutter rather than a smoothly executed display. Response times for displays reviewed here range from 12ms through 25ms. A typical CRT monitor has a response time in the 1-3ms range. If users require wire frame rotations or the animation of complex shaded models, they'll definitely see the difference between the two technologies.

  11. Reference • http://en.wikipedia.org/wiki/Thermionic_emission • http://findarticles.com/p/articles/mi_m0BLL/is_2_22/ai_n13487393/?tag=content;col1 • http://www.physicshandbook.com/topic/topice/electron%20emission.htm

More Related