Pulsed Ultrasound Flashcards
pulse duration (what/equation)
time it takes for one pulse to occur (doesn’t include down time)
PD= TxRD
ring down means
cycles in a pulse
spacial pulse length (what/equation)
length of the pulse
SPL= λxRD
Does decreasing SPL improve or worsen image resolution
improves
increasing f decreases λ which _____ SPL
decreases
decreasing the number of cycles in a pulse will ______ SPL
decrease
for PRF what unit should we use
meters and m/s
what is the limiting factor to PRF
depth (deeper takes longer)
pulse repetition period (what/equation)
time from the beginning of one pulse to beginning of the next
PRP=d/C, PRP=1/PRF
PRP is another way of expressing
the go return time calculated by the range equation
Duty factor (what/equation)
is the fraction of time that the pulsed ultrasound is on
DF=PD/PRP x 100
what two factors determine acoustic velocity
density and compressibility
if everything else remains the same, an increase in density will cause a _______ in acoustic velocity
decrease
If everything else remains the same, an increase in compressibility will cause a _______ in acoustic velocity
decrease