New 3-D Ultrasound Imaging Technique Uses A Single Sensor Instead of Thousands
New ultrasound device creates 3-D visualizations through compressive imaging and only has a single sensor.
While 3-D ultrasound imaging has been shown to produce high-resolution images with stunning detail, medicine has yet to fully embrace the technique due to complex hardware and high cost. Most medical ultrasound systems use transducer arrays with a line of sensors to create a 2-D cross-sectional image of the body, instead of using arrays of thousands of piezoelectric sensors that are typically needed for 3-D images.
In a new study, a team of Dutch researchers have designed a simple ultrasound device that can create 3-D images with a single sensor. The device avoids the hardware complications of conventional 3-D ultrasound through compressive imaging, a technique that projects image information through a set of what are known as incoherent functions onto a single measurement. This novel method could be used to make cheaper, faster and smaller systems for clinical applications.
Instead of a 2-D array of sensors, the novel device contains one large piezoelectric sensor that transmits an ultrasonic wave through a plastic aperture mask. The thickness of the plastic varies randomly across the mask, causing local delays in wave propagation, and scrambling the phase of the wave field. The interference pattern then passes into the medium, scatters from objects within the medium, and reflects back, traveling once more through the mask before reaching the sensor.
The researchers demonstrated the system by successfully imaging two plastic letters (“E” and “D”) positioned at different distances away from the sensor in 3-D. The technique moves the complexity of 3-D ultrasound imaging from hardware to computing and is also able to image faster than previous systems, which is crucial for many medical applications.