This cloaking shield.

0 Scrolling through reddit and I am utterly confused how this works.

In: Engineering

It is a material with bunches of tiny lenses embedded into it. This makes it blur incoming light from behind it while still allowing most of it to pass through in some direction.

Imagine a flat sheet of the material with a person standing a few feet behind it. Our person is wearing a blue jacket and the environment around them is yellow.

From what directions can light fall on the material? Basically from 180 degrees, half a sphere in direction right? But the person only takes up a relatively small number of those angles. What the material does is mix all that light together so what you see is mostly yellow with a small amount of blue instead of the clearly blue jacket.

It’s essentially a lens that spreads out the light horizontally, so any point sees a blur of everything on a large horizontal line. The person is only a small part of that, so is mostly invisible.

Works best with a background that varies vertically but not horizontally. Also only works great from certain positions. See this video for moving around similar lens. Also check the laser-pointer section in the middle to see the light path.