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What Would You Do With a Waterproof MEMS Microphone? Listen to Whales, of Course

Vesper built its waterproof piezoelectric microphones for mobile phones and the IoT, but they turn out to be pretty good for listening to whale songs

2 min read
A whale swims just under the surface of the ocean. Vesper's piezoelectric MEMS microphone can record underwater whale sounds without special housing
Photo: Kate Westaway/Getty Images

I first met Vesper CEO Matt Crowley around this time last year. Crowley said his startup had developed a prototype of a piezoelectric MEMS microphone that, he told me, was going to revolutionize the way mobile devices hear. Eventually, he said, every smart phone would have eight or more of these little microphones on board, they’d hardly use any power most of the time, and they would be the most reliable microphones we’ve ever seen.

Big claims, so I’ve been keeping an eye on Vesper since. Vesper doesn’t have their chips in any commercial mobile phones yet. But they come to mind every time a kid of mine manages to soak a cell phone and we’re both biting our nails hoping the possibly mythical rice trick works, because I know from experience it’s the microphone that’s the first thing to go when phone meets water. And I do I keep hearing more and more about piezoelectric microphone technology.

Vesper started in late 2014, coming out of a University of Michigan project aimed at using piezoelectric MEMS to create better microphones for uses as varied as aerospace and hearing aids. Conventional MEMS microphones have a backplate with an air gap separating it from the diaphragm; anything that gets in that gap—even a speck of dust or drop of water—can block that movement, killing the microphone. With piezoelectric MEMS microphones, the membrane generates electricity directly from the motion of soundwaves; there is no backplate. This is what makes them resistant to dust and water. That’s good news for people (like my kids) who drop their mobile devices in the toilet, run in heavy rainstorms, and go to dusty Burning Man.

Vesper has been collecting awards for its technology, most recently, Vesper chief technology officer Bobby Littrell received the Innovator of the Year Award in the annual Annual Creativity in Electronics competition held in San Jose in December. That same week the company scored US $15 million in venture funding, including an investment from Amazon’s Alexa Fund, to help bring its design to market.

But just because Vesper still has a lot to do to make its microphone happen doesn’t mean its engineers haven’t had time to enjoy the technology themselves. During his pitches to phone manufacturers, Crowley typically raves that the microphones will even work underwater. One manufacturer’s representative, Crowley said, asked him why anybody would want to record sound underwater. Crowley flashed on the movie Star Trek IVand its plotline surrounding an attempt to contact whales.  That led to him suggest a whale watch expedition for the next company outing, and to ask Vesper engineer Tung Shen Chew to put the microphone onto some kind of rig (basically a long pole) that would let them get it into the water.  “We got a lot of strange looks from the crew and other passengers, but once we explained what we were doing, they thought it was cool,” Crowley says. You can see a few whales—and hear their underwater sounds as recorded by the piezoelectric MEMS microphone—in the video above.

Next year, Burning Man?

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Digging Into the New QD-OLED TVs

Formerly rival technologies have come together in Samsung displays

5 min read
Television screen displaying closeup of crystals

Sony's A95K televisions incorporate Samsung's new QD-OLED display technology.

Sony
Blue
Televisions and computer monitors with QD-OLED displays are now on store shelves. The image quality is—as expected—impressive, with amazing black levels, wide viewing angles, a broad color gamut, and high brightness. The products include:

All these products use display panels manufactured by Samsung but have their own unique display assembly, operating system, and electronics.

I took apart a 55-inch Samsung S95B to learn just how these new displays are put together (destroying it in the process). I found an extremely thin OLED backplane that generates blue light with an equally thin QD color-converting structure that completes the optical stack. I used a UV light source, a microscope, and a spectrometer to learn a lot about how these displays work.

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