X RAY TUBE

• What is the main function of the anode in an X-ray tube?

  Convert electrons into X-rays and heat
• What does the filament in an X-ray tube do?

  Heats up to produce free electrons
• What is the purpose of the glass insert in an X-ray tube?

  Holds anode and filament, preserves vacuum
• How does tube oil function in an X-ray tube?

  Helps to cool the tube
• What is the role of the tube housing in an X-ray tube?

  Contains oil and shields against radiation
• What percentage of energy is converted into X-rays in an X-ray tube?

  1%
• What is the main requirement for producing X-rays efficiently?

  Minimize heat damage during production
• Why is it important to control the quality and intensity of radiation in X-ray tubes?

  To select and manipulate exposure factors
• What is the voltage range for X-ray tubes?

  40,000 – 100,000 Volts
• What is the purpose of the focusing cup in an X-ray tube?

  Minimize unsharpness by focusing the electron stream
• What material is typically used for the anode in X-ray tubes?

  Tungsten
• Why is tungsten preferred for the anode target area?

  High atomic number and melting point
• What is the melting point of tungsten?

  3,387 °C
• What does the cathode assembly consist of?

  Coiled tungsten filament and focusing cap
• What is the thickness of the tungsten filament wire?

  Approximately 0.2 mm
• Why is the filament coiled in an X-ray tube?

  To increase surface area for electron emission
• What is the function of the focusing cup in the cathode assembly?

  Prevents electron stream from diverging
• What materials are used for the glass envelope of an X-ray tube?

  Borosilicate glass, ceramics, metals
• What is the purpose of the tube oil in an X-ray tube?

  Removes heat by convection currents
• How does the tube housing contribute to radiation safety?

  Provides a lead lining to block radiation
• What is the function of the tube port or window?

  Directs X-ray beam towards the patient
• Why do rotating anodes require higher tube currents?

  To achieve very short exposure times
• What is the typical rotation speed of a rotating anode?

  3000 rpm
• What is the advantage of a rotating anode over a stationary anode?

  Distributes heat over a greater surface area
• What is the composition of the rotating anode disk?

  90% tungsten and 10% rhenium alloy
• Why is rhenium used in the rotating anode disk?

  Improves durability and reduces cracking
• How does the shape of the rotating anode disk aid in heat loss?

  Saucer shape improves heat loss via radiation
• What are the main components of an X-ray tube?

  • Anode (tungsten)
  • Filament
  • Glass insert/tube
  • Tube oil
  • Tube housing
  • Tube port/window
• What are the main requirements and challenges of X-ray tubes?

  • Efficient X-ray production
  • Heat damage reduction
  • Small focal spot for clarity
  • Control of radiation quality and intensity
  • Safety in radiation emission
• What are the differences between stationary and rotating anode X-ray tubes?

  • Stationary: fixed anode, limited heat dissipation
  • Rotating: anode rotates, better heat distribution, shorter exposure times
• What are the properties of tungsten that make it suitable for X-ray tubes?

  • High atomic number (Z=74)
  • High melting point (3,387 °C)
  • Good heat conductivity
  • Low vapor pressure
• What are the functions of the filament in an X-ray tube?

  • Generates electrons through thermionic emission
  • Increases surface area for electron release
  • Confines thermionic emission to a smaller area
• What are the cooling mechanisms in an X-ray tube?

  • Tube oil for convection cooling
  • Heat exchanger in high output tubes
  • Design of rotating anode for heat distribution
• What are the safety features of X-ray tube housing?

  • Lead lining for radiation shielding
  • Conductive sheath for electrical safety
  • Support for tube assembly and attachments
• What are the characteristics of the rotating anode disk?

  • Made of composite material (90% tungsten, 10% rhenium)
  • Saucer-shaped for improved heat loss
  • Two target areas for dual filaments
• What are the functions of the focusing cup in an X-ray tube?

  • Prevents electron stream divergence
  • Helps achieve a point source of X-rays
  • Increases electrical potential for focusing effect
• What are the properties of the glass envelope in an X-ray tube?

  • Made from borosilicate glass or ceramics
  • Acts as an electrical insulator
  • Maintains vacuum to prevent oxidation
• What are the advantages of using a rotating anode in X-ray tubes?

  • Higher tube loadings
  • Shorter exposure times
  • Better heat management
• What are the challenges associated with the use of tungsten in X-ray tubes?

  • Potential for vapor build-up
  • Need for high melting point
  • Risk of damage from electron bombardment
• What is the significance of the tube port in an X-ray tube?

  • Directs X-ray beam towards the patient
  • Area of low beam attenuation
  • Secured for alignment with light beam diaphragm