3 ms·
I don't think that makes sense; otherwise, why would the thickness of the lens matter at all?
by kenbellows 12y ago
I don't think that makes sense; otherwise, why would the thickness of the lens matter at all?
- vilhelm_s 12y agoThe shape of the lens puts the surface of the lens at the correct angle. You can make a thin lens by splitting it into many discontinuous parts, this is how a Fresnel lens works. See e.g. these two pictures: http://upload.wikimedia.org/wikipedia/commons/9/97/Lens3b.svg http://upload.wikimedia.org/wikipedia/commons/9/97/Lens3b.sv... http://en.wikipedia.org/wiki/File:Fresnel_lens.svg http://en.wikipedia.org/wiki/File:Fresnel_lens.svg
- tomswartz07 12y agoOP above is correct. The light will only bend at the interfaces between two mediums (air, glass).
- sp332 12y agoIt doesn't. Light can bend when it encounters a change in the index of refraction, e.g. air to glass or vice-versa. https://en.wikipedia.org/wiki/Refraction#Explanation https://en.wikipedia.org/wiki/Refraction#Explanation Light travels in a straight line after it has entered the glass, and again after it exits. Only the angle and the difference in refractive index matters. That's why you can build a Fresnel lens which is, so to speak, all surface. https://en.wikipedia.org/wiki/Fresnel_lens#Description https://en.wikipedia.org/wiki/Fresnel_lens#Description
- kenbellows 12y agothat's really interesting. apparently I need to read up