chapter 8 Flashcards
Transducer
is any device that converts one form of energy into another
what are the two functions of transducers
during transmission electrical energy from the system is converted into sound
during reception the reflected sound pulse is converted into electricity
Piezoelectric Effect
property of certain material to create a voltage when they are mechanically deformed or when pressure is applied to them
Reverse piezoelectric effect
piezo. material change shape when a voltage is applied to them
Piezoelectric or ferroelectric
material which convert sound into electricity
what are the peieozelectric material used in clinical transducers
lead, zirconate, titanate, or PZT
what are the synonyms of PZT
ceramic, active element, or crystal
What is the case of a transducer?
cylindrical tube, it protects the internal components of the transducer from damage. Insulates the patient from electrical shock
What is the electrical Sheild of a transducer?
Metallic barrier lining the inside of the case. prevents spurious electrical signals in the air. Helps prevent electrical noise from contaminating the clinically I,portant electrical signals used to create diagnostic images
Acoustic insulator
a thin barrier of cork or rubber that isolates or uncouples the internal components of the transducer from the case. Prevents vibrations in the case from inducing an electrical voltage in the PZT of the transducer
PZT or active element
The crystal. emitted by the transducer are related to the dimensions of the active element. is 1 half wavelength thick
wire
provides electrical connection between the PZT and the ultrasound system. the crystals vibrate produces a voltage that must return to the system for processing into an image
Matching layer
increasing the efficiency of sound energy transfer between the active element and the body
protects the active element
the matching layer is 1 half wavelength thick
Backing material
reduces the ringing of the PZT
another name for backing material
damping element
