Skip to main content

MIT’s new laser audio system can deliver secret messages directly to your ears

What’s the best way to communicate with a person when they’re outside of normal speaking distance? Call them on their phone, obviously. But what if the person either doesn’t have a phone with them — or you’re just looking for a high-tech communication method that’s a little more James Bond in its nature? Researchers from Massachusetts Institute of Technology have you covered with a new invention that makes it possible to literally beam an audible message to a specific person across the room using a laser. Because, you know, science.

“We have demonstrated that an eye-safe laser will heat the water molecules in the air, via the well-known photoacoustic effect, to create a local sound,” Ryan Sullenberger, a researcher who worked on the project, told Digital Trends. “We have also leveraged the special behaviors that occur at the speed of sound to help us amplify and localize the sound. If we rotate our laser beam, we can localize the sound not only along the laser path, but also isolate a specific range — the one at which the beam is moving at the speed of sound — at which the signal is amplified to an audible level.”

Recommended Videos

As noted, in most cases, calling someone’s phone is a whole lot easier than communicating with them via laser. That’s particularly true due to the fact that, unless both people possessed the same equipment, this is a one-way communication process only. However, Sullenberger noted that there are specific situations in which this could prove to be useful, rather than simply a cool proof-of-concept tech demo. For example, it could be used for gaining the attention of individuals in potentially dangerous situations when they are out of ordinary earshot.

Please enable Javascript to view this content

At present, the technique can be used to send sounds up to 60 decibels (equivalent to ordinary background music or a conversation in a restaurant or office) a distance of around 2.5 meters. But this distance could change in the future. “We are [next] hoping to make measurements at longer ranges [of around] 100 to 500 meters, outside, to better understand issues that might occur outside of a controlled laboratory setting,” Sullenberger said. “We are currently working on patenting the technology and would love to engage with interested parties.”

A paper describing the research was recently published in the journal Optics Letters.

Luke Dormehl
Former Digital Trends Contributor
I'm a UK-based tech writer covering Cool Tech at Digital Trends. I've also written for Fast Company, Wired, the Guardian…
Hyundai Ioniq 5 sets world record for greatest altitude change
hyundai ioniq 5 world record altitude change mk02 detail kv

When the Guinness World Records (GWR) book was launched in 1955, the idea was to compile facts and figures that could finally settle often endless arguments in the U.K.’s many pubs.

It quickly evolved into a yearly compilation of world records, big and small, including last year's largest grilled cheese sandwich in the world.

Read more
Global EV sales expected to rise 30% in 2025, S&P Global says
ev sales up 30 percent 2025 byd sealion 7 1stbanner l

While trade wars, tariffs, and wavering subsidies are very much in the cards for the auto industry in 2025, global sales of electric vehicles (EVs) are still expected to rise substantially next year, according to S&P Global Mobility.

"2025 is shaping up to be ultra-challenging for the auto industry, as key regional demand factors limit demand potential and the new U.S. administration adds fresh uncertainty from day one," says Colin Couchman, executive director of global light vehicle forecasting for S&P Global Mobility.

Read more
Faraday Future could unveil lowest-priced EV yet at CES 2025
Faraday Future FF 91

Given existing tariffs and what’s in store from the Trump administration, you’d be forgiven for thinking the global race toward lower electric vehicle (EV) prices will not reach U.S. shores in 2025.

After all, Chinese manufacturers, who sell the least expensive EVs globally, have shelved plans to enter the U.S. market after 100% tariffs were imposed on China-made EVs in September.

Read more