Build Your Own Invisiability Device for Under $150

Researchers at the University of Rochester create a 3-D, transmitting, continuously multidirectional cloaking device. ... and they say you can too!
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To build your own Rochester Cloak, follow these simple steps:

For their demonstration cloak, the researchers used 50mm achromatic doublets with focal lengths f1 = 200mm and f2 = 75mm

1. Purchase 2 sets of 2 lenses with different focal lengths f₁ and f₂ (4 lenses total, 2 with f₁ focal length, and 2 with f₂ focal length)
2. Separate the first 2 lenses by the sum of their focal lengths (So f₁ lens is the first lens, f₂ is the 2nd lens, and they are separated by t₁= f₁+ f₂).
3. Do the same in Step 2 for the other two lenses.
4. Separate the two sets by t₂=2 f₂ (f₁+ f₂) / (f₁— f₂) apart, so that the two f₂ lenses are t₂ apart.

NOTES:

• Achromatic lenses provide best image quality.
• Fresnel lenses can be used to reduce the total length (2t₁+t₂)
• Smaller total length should reduce edge effects and increase the range of angles.
• For an easier, but less ideal, cloak, you can try the 3 lens cloak in the paper.

A patent has been filed for this cloaking device. Please contact UR Ventures for additional information.