they can read your notes from a mile away

[scruffy]

You've heard of the lasers that can read your computer screen by targeting your window?

Well, here's the latest version: it doesn't even have to be a computer screen anymore. Now they can even read your tiniest handwritten notes.

The technology works off "synthetic aperture interferometry", a version of the same thing as synthetic aperture radar. It uses the thermal properties of light.

“We Can Read Your Secrets From a Mile Away”: China Unleashes Laser Tech That Detects Sesame-Sized Text With Brutal Precision

Imagine standing on one side of a vast valley, effortlessly reading the label on a bottle perched on the opposite hill. No binoculars, telescopes, or cameras

www.sustainability-times.com

https://link.aps.org/doi/10.1103/PhysRevLett.134.180201

 

[toobfreak]

You've heard of the lasers that can read your computer screen by targeting your window?
Well, here's the latest version: it doesn't even have to be a computer screen anymore. Now they can even read your tiniest handwritten notes.

Actually, my biggest problem these days has been the spy the CIA buried in the wall of my bedroom! I can hear him in there scratching at night, listening, while I'm trying to get to sleep.

The technology works off "synthetic aperture interferometry", a version of the same thing as synthetic aperture radar.

Actually, this is nothing new, just a new way of applying it. They are getting away from the "normal" physical constraints of Dawes Limit of light limiting angular resolution over distance, and the bulkiness of needing increased aperture for increased resolution along with giving the needed additional light grasp and focal length by using a synthetically generated aperture.

Instead of a full, contiguous aperture, it relies on only using a tiny portion of the aperture separated by the full diameter distance of the intended (effective) aperture, then the computer taking these two samples and reconstructing what the rest of the aperture must have been to cause that.

They have been using variants of similar technology for many years by spacing two telescopes wide apart then using a type of interferometry to simulate a far bigger telescope too big to build on Earth, then have even used it in radio science by placing radio telescopes on opposite sides of the Earth then combining them to create one synthetic aperture the size of our planet in order to see in radio "light" to the far ends of the universe.