Proton precession magnetometer
thesisposted on 2022-03-28, 18:47 authored by Arefin Islam Ayon
Magnetic resonance imaging (MRI) is a medical imaging technique to produce images of the anatomy and physiological processes of the body. MRI devices use very strong magnetic fields and radio waves to process these images of the human body. MRI is based on the physical principle of nuclear magnetic resonance (NMR). This is a phenomenon where and atom's nucleus, placed in an external magnetic field, absorbs and emits radio frequency. The cost of a conventional clinical MRI scanner is in the order of 2-3 million dollars and additional maintenance and operating costs make a single MRI exam cost about $1000. Also, sometimes, an MRI of the entire body is not required. From this originates the idea of this project, which is to prototype a proton precision magnetometer (PPM), which will lead us to explore the possibilities for cheaper MRI technology. This magnetometer will be first prototyped to measure the earth's magnetic field, but in the longer term it can be further extended for other industrial and biomedical applications. Similar to clinical MRIs, the PPM relies on the signal from processing nuclear magnetic dipoles. The frequency of the precession is directly proportional to the external magnetic field strength. And when there are enough precessing protons resulting, an oscillating magnetic field will be created. The frequency of the generated oscillating field is exactly what we will be measuring with the PPM which will correspond to earth's magnetic field.