Forward-looking: Biometrics is advancing and evolving at a rapid rate. It seems like just yesterday we were unlocking our phones with our fingerprint --- now it's our face. What's it going to be tomorrow --- our heartbeat? Well, maybe.

MIT Technology Review reports that the Pentagon now has a prototype infrared laser that can identify people by their heartbeat. It is called "Jetson" and uses laser vibrometry to detect movements on the surface of the skin caused by a person's pulse. It even works from as far as 200 meters away.

If you grew up reading Daredevil comic books, you already know that everyone's heartbeat is unique, which is how the super-powered blind Matt Murdock was able to identify people. Jetson works similarly.

By detecting a person's heartbeat, then comparing it to a database, the laser can ID someone with 95-percent accuracy in optimal testing conditions. Of course, the most significant advantage is that it cannot be fouled up like facial recognition and fingerprint sensors since a heart rhythm can't be duplicated or changed.

"Compared with face, cardiac biometrics are more stable and can reach more than 98% accuracy," Wenyao Xu of the State University of New York at Buffalo, who has also developed a cardiac sensor that uses radar from up to 20 feet away.

"Existing long-range facial recognition [systems] suffer from acquiring enough pixels at a distance to use the face matching algorithms."

There are some caveats though. While the laser can detect a heartbeat from a distance on bare skin or through thin material like a tee shirt, thicker clothing like a jacket makes it ineffective. The system also needs about 30 seconds to create a good enough profile for analysis. The subject must be still during that time as well.

According to some 2017 documents from the Combating Terrorism Technical Support Office (CTTSO), Jetson has been in development for several years, and it is looking to decrease response time down to under five seconds.

"Existing long range biometric methods that rely on facial recognition suffer from acquiring enough pixels at a distance to use the face matching algorithms and require high performance optics to acquire visual signatures at significant distances," said the CTTSO. "The Jetson effort being developed by Ideal Innovations, Inc. is a ruggedized biometric system that will capture cardiac signatures to aid in the positive identification of an individual at a distance up to 200 meters and within five seconds."

The Pentagon is looking at if for military and surveillance applications, but there are several practical and commercial possibilities as well.

As previously mentioned, such technology could be used as a biometric solution for mobile devices. In fact, Apple has been looking into similar technology since at least 2010. It could also be used in medical and clinical situations. Wireless heart monitors are a possibility as are stethoscope-free checkups with your doctor. Badge-less entry systems for secured buildings would be another use case.