New beam pattern yields more precise radar, ultrasound imaging

University of Rochester researchers have developed a novel beam pattern that promises to lend unprecedented sharpness to ultrasound and radar images.

The beam's mathematical pattern yields wavelengths that momentarily collapse in on themselves, briefly forming a precise and powerful beam of sound or light waves.

"All the energy fits together in time and space so it comes together -- BAM! -- like a crescendo," Kevin Parker, a professor of engineering at Rochester, said in a news release. "It can be done with an optical light wave, with ultrasound, radar, sonar -- it will work for all of them."

Researchers say the pattern could also be used to make precise incision and holes in nanoscale structures or etch fine patterns into the surface of materials.

Unlike other beam patterns, which often dissipate some energy laterally in the form of "side lobes," the new beam patterns is extremely efficient.

"Side lobes are the enemy," said Miguel Alonso, a professor of optics. "You want to direct all of your ultrasound wave to the one thing you want to image, so then, whatever is reflected back will tell you about that one thing. If you're also getting a diffusion of waves elsewhere, it blurs the image."

The work of Parker and Alonso -- detailed in the journal Optics Express -- continues Rochester's tradition of breakthrough beam discoveries. In 1986, a time of Rochester physicists discovered a now widely used pattern known as the Bessel beam.

"It had been decades since anyone formulated a new type of beam," Parker said. "Then, as soon as the Bessel beam was announced, people were thinking there may be other new beams out there. The race was on. Finding a new beam pattern is a like finding a new element. It doesn't happen very often."