The concept drew increased attention with the first novel in the J.K. Rowling series “Harry Potter and the Sorcerer’s Stone” where an invisibility cloak once owned by his father is passed onto him. In the book, Potter is able to become invisible by covering himself with the cloak. In 2006, scientists at Duke University created a mini-version that successfully made objects invisible with some limitations.
That early invisibility cloak prototype had trouble with light refraction and in practice worked much like a window on a sunny day; you can see through the window but also notice the presence of the glass due to light being reflected.
Now, Dr. Landry of Drake University has an improved prototype which has addressed the light refraction problem and which he claims makes an object “invisible”.
Landy explained to Phys.org that “it was much like reflections seen on clear glass. The viewer can see through the glass just fine, but at the same time the viewer is aware the glass is present due to light reflected from the surface of the glass.”
The new version consists of four quadrants which are configured to negate light refraction and blind spots. Dr. Landry believes this this prototype is the first one to get invisibility “exactly right”.
“When the scattered fields from the cloak and the object interfere, they cancel each other out and the overall effect is transparency and invisibility at all angles of observation,” said Andrea Alu, one of the physicists.
Like many inventions first created story books or films, the Potter cloak may one day become a reality.
Scientists Create Perfect Harry Potter Invisibility Cloak
Making a better invisibility cloak