Get smart curated videos delivered to your inbox every week.      
The Kid Should See This

The ‘magic’ of invisibility lenses

Using lenses to bend light, YouTuber Brusspup makes a ruler, a knife, a spoon, a hand, and a laser completely disappear from view. Invisibility lenses create the illusion, an optical trick based on The Rochester Cloak, multidirectional cloaking experiments from the University of Rochester.


Brusspup describes what’s happening in the video notes:

It uses 4 lenses to control light in such a way that it renders an object invisible. When the light enters the first lens, it flips the image upside down. The second lens sends the light straight into the 3rd lens. The 3rd lens focuses the light into a point about 3 inches past the lens. Since the light is focused into a point, any object placed around that point cannot be seen when looking through the lenses. The light is essentially bending around the object. Once the light hits the point just past the 3rd lens, it then flips back right side up. This allows the background image to pass through all of the lenses without warping or being seen as upside down.


This Outrageous Acts of Science video explains further:


And this University of Rochester video demonstrates the original work:

Follow these with this 2013 uni-directional demonstration of optical cloaking.

Plus, create pattern distortions seen through a glass of water, the Reversing Arrow Illusion, and another illusion: How to make a 3D “hologram” using your smartphone & a CD jewel case.

This award-winning video collection is reader-supported. Become a sustaining member to keep TKSST online and free for everyone, including teachers and parents who use it as a resource to spark learning and curiosity for kids.

🌈 Watch these videos next...

How they made Fred Astaire’s famous dance scene in Royal Wedding (1951)

Rion Nakaya

ExpeRimental: How to Make Static Magic

Rion Nakaya

Amazing Moving Cube

Rion Nakaya

Make a 3D “hologram” using your smartphone & a CD jewel case

Rion Nakaya

Planet-changing ‘invisible’ microbes on the deep sea floor

Rion Nakaya

How to make amazing anamorphic illusions

Rion Nakaya

Levitating pumpkins! Halloween superconductor science

Rion Nakaya

Les machines impossible, an animated series for the Centre Pompidou

Rion Nakaya

The World in UV

Rion Nakaya