Camera that can see through you.

Sci-fi is replete with references of spectacles that help the wearer see through the clothing of adversaries. Turns out the writers may have been prescient as researchers have developed a powerful holographic camera that can see through ( and around) almost anything, including corners, fog and even human flesh. The implications of the technology are significant as it could be commercially developed for vehicular, defence and even medical uses. Here's how it works.

The Technology

* This is relatively new field of research known as non-line-of-sight (NLoS) imaging and this technique can rapidly capture full-field images of large areas.

* It does so with submillimeter precision, a level of resolution that an AI-driven camera could use to see through the skin and see even the smallest capillaries working.

* An algorithm reconstructs the scattered light thrown by objects outside our line of sight and then reconstructs them on a computer.

* Due to its high resolution, the method also has potential to image fast-moving objects such as a beating heart through the chest or speeding cars around a street corner.

* It could replace endoscopes used in medical and industrial imaging by using light to see around the folds inside the intestines instead of sending a flexible camera for a colonoscopy procedure.

Prior Research on non-line-of-sight

In September, Stanford researchers had come up with a keyhole imaging technique that lets people outside shine a laser through keyhole to find out what's inside a room without going in.

The nitty-gritty

Whether it is to see around a corner or look at a pumping heart inside the body, the solutions are actually closely related, researchers said. This is because both rely on scattering media in which light hits an object and scatters in a way that a direct image is no longer possible.

The goal of the project was to intercept scattered light in order to reconstruct the information contained within the light, including its time of travel. Nothing is faster than the speed of light, so if you want to measure the time with high precision then you need extremely fast detectors.

The team wanted to find a way to get rid of fast detectors and did so by merging light waves from two lasers in order to generate a synthetic light wave. This can be tailored to holographic imaging. If you can capture the entire light field in a hologram, you can then reconstruct its 3D shape in full.

Statistics

* Built by - Northwestern University in Evanston, Illinois

* Technique - Synthetic wavelength holography (SWH).

* SWH - A holographic representation of hidden or obscured targets.

* Wavelength - Infrared.

* Status - A decade away from commercial exploitation.

* Intended uses - Cars, CCTV and even as a medical scanner.

Why Earlier Attempts Were Not Successful?

Previous attempts at using NLoS techniques to recover images of hidden objects suffered from very low resolution and a small angular field. Other issues were the scan duration or the requirement of a very large probing area to measure the scattered light.

My take.

This is gonna be revolutionary!

Tailpiece.

Got up at 6, the chores and was ready by a quarter to 10. The maid had to get some official work done and therefore, took an off today. 

Lekha and I had gone in an autorickshaw to buy our weekly fruit basket, grocery and fresh fish for Kittu.

It has become the habit of the Kittu family to spread themselves - he, Ms Kittu and their three kittens - on the ex-barn roof, just across our balcony. They make an interesting sight!