Physic (Medical Imaging & Laser Surgery) Coursework

Physic (Medical Imaging & Laser Surgery) - Coursework Example The wavelength reduces with the increase of absorbed energy (Zettili, 2009). The wavelength for visible light is in the range of 750nm-400nm. X-rays wavelength is in the range of 10nm upward. The wavelength of x-rays is extremely short as compared to the wavelength of visible light. The order of absorbency for x rays from the most absorbent to the least absorbent for the following materials is as follows: copper, glass, wood and air while the order of absorbency for visible light is as following: air, wood glass and lastly copper. From the list it can deduced that the order of absorbency of X rays is exactly vice versa to that of visible light for the mention materials (Kusky and Cullen, 2009). When the produced x-ray is passed through the body, some part of the energy is absorbed by the body during the rest pass. The opposite side of the body is a plate containing a film that detects the X- rays and captures the attenuated x-rays. As x-ray emerges from the body, it contains an image in the form of variation in exposure across the image area. Variations are as a result of different rate of attenuation of x ray by the object. The plate is sprayed with powder that adheres to the charged areas hence electrostatic charge is formed. The heavily charged areas produce more detailed information as powder gathers more quickly in those areas. X rays are more attenuated by denser material than light material; therefore bones will attenuate more rays than fats and muscles. From the above picture, the bones are clearly seen (denser material) while muscles, blood and fats cannot distinctly be seen. Shadings show them. The CT scanner uses x-rays that are emitted in a fan shape to produce 3D images of objects. It has rotating gantry with x-ray tube mounted on it and arc shaped detector. When the x-ray beam is aligned by collimator and emitted, the rotating frame spins the tube and detector by 360 degrees