Clover Learning's video: The X-Ray Tube Components

Visit www.radtechbootcamp.com TODAY to view the rest of the videos in this series. In this video, we will be discussing the x-ray tube and its components. Without the x-ray tube, diagnostic imaging such as plain film x-ray, fluoroscopy, and computed tomography would not exist. The first generation of x-ray producing tubes was the Crookes tube. This simple tube included two electrodes that were placed at opposite ends of a semi-vacuum tube. Crookes, as well as other physicists, discovered that when high voltage electricity was delivered to opposite ends of the tube, that electrons would flow within the tube in a straight line. Through the use of the Crooks tube, Wilhelm Conrad Röntgen was able to both discover X radiation along with producing the first x-ray image. In 1913 a physicist and engineer named Edward Coolidge invented what would be known as the Coolidge tube. The Coolidge tube provided the framework of what we know today as the modern x-ray tubes. This image represents the x-ray tube and components. Every x-ray tube is protected by a metal housing. Within the metal housing lay both the x-ray tube And oil cooling layer. The oil layer is also used to both protect against electroshock as well as absorbed unnecessary leakage radiation. The national council for radiation protection requires that radiation leakage must fall below 100mRoentgens /h at one meter or 3.2 feet from the tube. The components of the x-ray tube are housed inside a vacuum glass pyrex tube or metal case that is free of all gases. The absence of oxygen gas within the tube allows for greater efficiency of x-ray production, as well as helps extend the life of the tube. Within the cathode lay the focusing cup. Most standard x-ray tubes will have two filaments within the focusing cup, one small and one large. The large filament within the cup allows for greater technical factor, where the small filament is used to increase image detail. The term dual-focus cup is used to describe a focusing cup with two filaments. The filaments used within x-ray production are similar to those found in older plight bulbs or kitchen toasters. The one fundamental difference with x-ray tube filaments is that they are composed of the heat resistant material tungsten, Opposite to the cathode and focusing cup is the positively charged anode. I remember the charges of the anode and cathode by, I want an A+ in class, not C-. There are two types of anodes used in diagnostic imaging, the stationary and rotating. Stationary anodes are typically smaller and are used in both Portable x-ray units along with dental imaging systems. Due to their small target area, stationary anodes are limited in their ability to producing high mAs exposures. For example, a portable x-ray unit with a stationary anode might only be able to produce a maximum exposure of 100 kvp @ 60 mAs. The Rotating anode, which is labeled B, is what you will find in all clinical and computed tomography x-ray systems. Rotating the anode creates almost 500 times more surface area as compared to the stationary anode. This increase in surface area allows for an increased in Ma settings as well as an increase in exposure times. The area where the x-ray photons are created is known as the target area. The dark coloration within the anodes symbolizes the target area of both the rotating and stationary anode. Tungsten is most often used within the anode targets due to its high atomic number of 74. This high atomic number not only allows for greater heat dissipation but also aids in photon production This sums up the major components of the x-ray tube. More advanced topics concerning the x-ray tube will be discussed in further videos.