Basic Production Of X-Rays

Basic Production Of X-Rays

Describe the parts of an X-ray tube and add a note on X-ray production.
or
Described parts of an X-ray tube along with a note on production of X-rays
Answer. For parts of an X-ray tube refer to Ans 1 of same chapter.

Production of X-rays

“Importance of studying X-ray production for better imaging outcomes: Questions explained”

• X-rays are produced in X-ray tube. When the X-ray machine is turned on, the electric current enter the control panel; via the plugged in cord and then to the tube head via extension wires in extension arms.
• The current is directed to the filament circuit through the step-down transformer, it reduces the 110 to 220 voltage to 3 to 5 volts.
• The filament circuit uses the 3 to 5 volts to heat the tungsten filament. The hot filament emits electron, this emission of electron from the cathode is known as thermionic emission. It forms the electron cloud around the cathode.
• When the exposure button is pushed the high voltage current is activated and the electron cloud is accelerated in X-ray tube from cathode to anode.
• Molybdenum cup of cathode directs the electron to the anode target in narrow beam.

“Understanding the process of X-ray production: Q&A explained”

• When the electron strikes the tungsten target, their kinetic energy is converted to X-ray energy. Less than 1% of the energy is converted to X-rays, the remaining 99% is lost as heat.
• The heat produced is carried away by copper stem and absorbed by the insulating oil in the tube head.
• The area where electron strike on tungsten (anode) is known as focus spot (Tungsten focus).
• Produced X-rays only exit from the X-ray tube via unleaded glass window portion of tube.
• X-rays travel through the unleaded glass window, the tube head seal, the aluminum discs, which filter the long wave X-rays from the beam.
• The size and shape of the X-ray beam is controlled by the lead collimator. X-ray beam then travels down the lead lines position indicating device and exit the tube head at the opening of position indicating device.
• X-rays produced in the X-ray tube vary in their energy and their wavelength, depending on how electrons interacted with tungsten atoms in anode. So kinetic energy of electrons is converted to X-ray photon either through Bremsstrahlung radiation or through characteristic radiation.

General (Bremsstrahlung Radiation or Breaking Radiation)

• The term refers to the sudden breaking of high-speed electrons when they hit the tungsten target in the anode. About 70% of the X-rays are produced in this manner.
• If the electron hits the nucleus of the tungsten atom, all its kinetic energy is converted into a “High Energy X-ray Photon”.
• But most of the time, instead of hitting the nucleus, most electrons just miss the nucleus of the tungsten atom. When the electron comes close to the nucleus, it is attracted to the nucleus and slows down, consequently, an X-ray photon is released. The electron that misses the nucleus continues to penetrate many such tungsten atoms producing many lower energy X-ray photons, before it imparts all its kinetic energy.
• As a result general radiation consists of X-rays of many different energies and wavelengths. It is also known as continuous spectrum.

“Common challenges in explaining the basic production of X-rays: FAQs provided”

x-ray production

Characteristic Radiation

• It is produced when a high speed electron dislodges an inner shell electron from tungsten atom and leads to ionization of atom. Once the electron is dislodged remaining orbiting electrons are rearranged to fill the vacancy. This rearrangement causes loss of the energy which results in the X-ray photon, with the energy equal to the difference in two orbital energy states. So X-rays produced are known as characteristic radiation.

“Factors influencing success in X-ray production: Q&A”

Bremsstrahlung process in radiology

how are x-rays produced

• This radiation accounts for very small part of X-rays which are produced in dental X-ray machine and occur at 70 kVp and above.