14 DAY TRIAL // It might have taken months upon months, even years, for the science behind light refraction to be understood well enough for invisibility cloaks to become feasible.
Once that was done, however, some researchers at Zhejiang University in China managed to perform the next step quite fast.
Which is to say, they created a very fast method for actually making those things.
And they didn't even rely on metamaterials (synthetic materials that alter the behavior of light as it interacts with objects). Instead, they used Teflon.
That's right, the physicists created a method that will make a Teflon invisibility cloak in around 15 minutes. All thanks to topology optimization.
That's the material nowadays used to make frying pans, for anyone who doesn't know.
Alas, the use of Teflon also means that the cloak, “Teflon eyelid” as it is called, only hides things from infrared scans, so it's not a true invisibility cloak in the end. Alas.
Then again, when it comes to sneaking into a secret base that relies on infrared cameras, you don't need much else.