ABSTRACT
The physics of Magnetic resonance imaging (MRI) is very complicated, and physicists are constantly working for major manufacturers to create new or improved scanning sequences. A transducer generates ultrasound pulses which are transmitted into tissues and echoes are detected as they return to the transducer. The Doppler shift is very small compared to the ultrasound frequency, and the resultant signals when processed produce sounds in the kHz range that are well within the human audible range. The maximum possible Pulse repetition frequency (PRF) and maximum recordable Doppler shift are dependent on the sample depth, since the next ultrasound pulse should not be emitted before all information from the previous pulse is received. A laser system consists of a gain medium, a power source supplied as an electric current or another light and a resonant chamber with mirrors. Intense pulsed light (IPL) uses a filtered flash lamp device that emits radiation between 420 and 1300 nm.
