Question

A 10 MHz transducer produces four cycles of ultrasound waves in each pulse. The estimated axial resolution of this transducer in water (c = 1500 m/s) will be __ mm.

Answer 1

The axial resolution of a 10 MHz ultrasound transducer in water is estimated to be 0.075 mm, which is half the wavelength of the ultrasound waves produced by the transducer.

Step-by-step explanation:

The student is asking about the axial resolution of an ultrasound transducer with a frequency of 10 MHz in water, where the speed of sound is 1500 m/s. To estimate the axial resolution, we first need to calculate the wavelength (λ) of the ultrasound waves using the formula λ = c / f, where c is the speed of sound in water (1500 m/s) and f is the frequency (10 MHz or 10×106 Hz). Then, the axial resolution is approximately half the wavelength because it is the smallest distance that separates two points to be distinguishable. The estimation of axial resolution is essential in imaging techniques, such as medical ultrasounds, because it determines the level of detail that can be observed within the body.
First, we calculate the wavelength:

λ = c / f = 1500 m/s / 10×106 Hz = 0.15 mm

Now we estimate the axial resolution as half the wavelength:

Axial resolution = λ / 2 = 0.15 mm / 2 = 0.075 mm

The estimated axial resolution of this transducer in water is 0.075 mm.