* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download X-ray tube - El Camino College
Survey
Document related concepts
Transcript
1 2 3 4 5 THE X-RAY TUBE REVIEW OF X-RAY DISCOVERY CROOKE’S TUBE WILHELM ROENTGEN’S OBSERVATIONS November 8, 1895 BERTHA ROENTGEN’S HAND 6 THE X-RAY TUBE CATHODE ANODE VACUUM GLASS ENVELOPE CURRENT 7 THE X-RAY TUBE Simple car battery 8 THE X-RAY TUBE 9 10 THE X-RAY TUBE anode cathode X-ray tube Glass envelope Tube housing 11 THE X-RAY TUBE Focusing cup cathode Tungsten filament Milli ampereage Thermionic emission Electron cloud 12 THE X-RAY TUBE 13 THE X-RAY TUBE target anode High voltage tungsten Rotating Focal track 14 THE X-RAY TUBE 15 THE X-RAY TUBE What do you need to produce ionizing radiation? 16 THE X-RAY TUBE A source of electrons A force to move them quickly Something to stop them very suddenly 17 THE X-RAY TUBE 18 THE X-RAY TUBE 19 THE X-RAY TUBE 20 THE X-RAY TUBE anode cathode X-ray tube Glass envelope Tube housing 21 THE X-RAY TUBE Cathode Anode filament Target/focal track Focusing cup rotor Milliamps kilovolts 22 THE X-RAY TUBE Glass Envelope Tube Housing vacuum Lead and steel Pyrex glass Surrounds anode and cathode Port for exit beam Surrounds glass envelope 23 THE X-RAY TUBE 24 THE X-RAY TUBE anode cathode Glass envelope Lead casing oil Port/window steel casing Which end of tube is the positive end? Which end is the negative end? Is this a stationery or rotating anode? 25 THE X-RAY TUBE What is electromagnetic spectrum? What are photons? What is radiation? What is ionizing radiation? What is x-ray? What are roentgen rays What are photons? 26 THE X-RAY TUBE Electromagnetic Radiation Bits of energy that passes thru matter Travels at the speed of light Not always ionizing!!!! photon 27 THE X-RAY TUBE Electromagnetic Energy Spectrum 28 29 30 31 32 33 THE X-RAY TUBE TThe amount of time charged is applied The amount of electrons burned off 34 THE X-RAY TUBE The amount of electrons burned off • • • • • Milli-amperage Electron cloud Thermionic Emission Focusing cup ??amount of electrons??? • ? How many mA are applied? 35 THE X-RAY TUBE • • • • The longer the the milli-amps are applied, the more electrons are burned off. The amount of time charged is applied • How many seconds are • applied? 36 THE X-RAY TUBE The stronger the force of the positive charge, the faster the electrons rush toward anode, The more x-rays are generated. The force of the charge is measured by kilovoltage (kV) applied to the anode 37 THE X-RAY TUBE milli-Amperage (mA) Time-(in fractions of seconds) kilo-Voltage (kV)(kVp) technique 38 CONTROL PANEL Where the technologist controls the x-ray machine Where technique selection occurs Always located outside the x-ray room 39 CONTROL PANEL 40 CONTR0L PANEL kVp controls Strength of beam kVp more penetrating 50-110 kVp in diagnostic x-ray Controls contrast and density on image 41 CONTROL PANEL mA controls the amount of electrons Time controls how long the electrons are sent to anode Frequently used as a single unit of measure mAs Controls the density of the image 42 ANCILLARY EQUIPMENT Image Receptors Table Tube supports Grids Collimators Misc Equipment 43 IMAGE RECEPTORS Film cassettes CR cassettes Direct imaging Bucky tray(grid) Wall Bucky tray(grid) 44 IMAGE RECEPTORS Film Cassettes are light tight, with intensifying screens. They serve to hold the film safe from any damage. CR cassettes look almost identical but contain a PSP plate that is used to create the image. 45 IMAGE RECEPTORS 46 TABLE 47 TABLE 48 TABLE 49 TUBE SUPPORTS Tube Suspension systems are available in 5 versions. Be sure to check the book for configurations. 50 TUBE SUPPORTS Designed to help technologists with various tube locations for creative imaging. 51 TUBE SUPPORTS Tube Movement Longitudinal Transverse Vertical Angling or Rolling Rotating Telescoping 52 COLLIMATORS Limits the X-ray field Limits the transverse and longitudinal field Positive beam limitation 53 COLLIMATORS 54 COLLIMATORS Always collimate smaller than the image receptor 55 GRIDS Device used to “clean up” the x-ray image by reducing the amount of scatter radiation reaching the image receptor Used on larger, thicker parts Built with parallel lead strips to absorb the scatter radiation 56 GRIDS ??? + - Primary beam Exit Radiation 57 GRIDS No grid grid 58 GRIDS 59 MISCELLANEOUS EQUIPMENT Positioning sponges Tape Lead aprons Lead blockers Markers Sand bags linens 60 MISCELLANEOUS EQUIPMENT 61 MISCELLANEOUS EQUIPMENT 62 63 64 65 PROCESSING ROOM Film Screen Image Production Digital Image Production 66 PROCESSING ROOM-IMAGE PRODUCTION ??? + - Primary beam Exit Radiation 67 PROCESSING ROOM-IMAGE PRODUCTION RADIOGRAPH- PERMANENT RECORD OF IMAGE, BY FILM OR BY COMPUTER STORAGE 68 DARK ROOM 69 DARK ROOM 70 DARK ROOM Pass Box Lockable from inside, contains cassettes Clean, dry, dustless countertop Work space be free of clutter Safe light 15 watt bulb 3 feet from film, countertop Orange or amber filter/light bulb, depends on film emulsion type Cassettes, empty and full Film bin Must be light tight Sometimes locks with door Processor Needs water supply, Must be clean Chemicals Store safely 71 DARK ROOM 72 DARK ROOM 73 CR READER CR - Computed Radiography Computed Radiography is an indirect type of imaging system. The receptor used within a CR cassette is called a photostimulable imaging plate (PSP) and it absorbs the radiation exiting the patient. The exposed plate is processed in a CR reader, where the absorbed energy is extracted. The information stored in the CR imaging plate must be processed before viewing can occur. The resultant latent image data is converted from an analog to a digital signal and a digital image is created. Computed Radiography x-ray systems predominantly use conventional xray tube systems. 74 CR READER 75 REVIEW 76 REVIEW 77 REVIEW 78 REVIEW A source of electrons A force to move them quickly Something to stop them very suddenly 79 THE X-RAY TUBE 80 4 3 3 5 6 8. Describe tube travel 1 7. Describe Tube Travel 2 9. Describe how the tube would travel in order to direct xray output at #1?? 81