What inventions (or other wise) use light refraction?

Spectacles, microscopes, telescopes

 

All kind of optic devices. A simple lens, for example.

Bob.

 

A man on The Science Channel said something interesting. Noting that the ability of a lens to focus relies on the light changing speed when it crosses the boundary between two substances, and noting that the eye needs a lens, the man on TV pointed out -- and this is a close paraphrase: "If light traveled at the same speed in all materials, everyone would be blind."

 

prism , binocluors , beam splitter , gravitational lensing ( bending light around the sun for example) , camera , magnyfing glass , x-ray prisms , cerenkov radiation in a nuclear reactor . x-ray rainbows

 

I wonder if somewhere in evolutioniary history some organisms have had eyes which work on the same principle as the pinhole camera.There is no refraction needed with these.

 

Snakes have a 'pit organ' for thermal vision that works similarly to a pinhole camera.

http://www.physorg.com/news76249412.html