Questions tagged [optics]
Optics is the study of light, and its interaction with matter. It includes topics such as imaging systems, fiber optics, lasers, quantum optics, and more.
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Do sunrises and sunsets look the same in a still image?
A question that popped into my head: if I see a picture of the sun close to the horizon, in an unknown place, can I know if it was taken at sunset or sunrise?
Do sunrises and sunsets look the same in ...
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Why does the sun have to be nearly fully covered to notice any darkening in an eclipse?
I was looking at eclipse footage and I noticed that it doesn't get any noticeably darker until the very end when it suddenly all the light is gone. As the moon blocks out the Sun, I would expect that ...
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Why do some lights captured by the Webb telescope have rays and others don't?
On the images captured by Webb telescope one can see some lights with 6 rays, but most others don't have any. One would expect the optics to transform all light sources at infinity in the same manner. ...
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Could a human beat light in a footrace?
Is there anything preventing the following experiment from being done right now?
Imagine that a human ran from point 'a' to point 'b' while light
particles that reflected off a clock moved ...
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What is this wavy light coming through my blinds?
On many mornings I get this cool light pattern on my ceiling:
It's light coming in through the blinds, but there is this rippling/wavy/moving effect. Its intensity varies (as can be seen a little in ...
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How many atoms does it take for us to perceive colour?
Atoms individually have no colors, but when there is a large collection of atoms we see objects colorful, which leads to a question: at least how many atoms are required for us to see the color?
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Do gravitational lenses have a focus point?
Do gravitational lenses have a focus point? Could I burn space ants?
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What causes the Sun to appear to be in front of a building in this picture?
I took this photograph a few days ago, during sunrise, using my smartphone camera and digital zoom:
It seems that the sun is in front of the building. How is this explained?
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Why doesn't a typical beam splitter cause a photon to decohere?
In many experiments in quantum mechanics, a single photon is sent to a mirror which it passes through or bounces off with 50% probability, then the same for some more similar mirrors, and at the end ...
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What wavelengths of light does a banana reflect?
I do know that there are at least two types of yellow light: a light of a single wavelength of ~580 nm and a combination of green light and red light. (Technically, there could be more yellow light.) ...
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Why are gold mirrors yellow?
Why are golden mirrors yellow?
Do they add a yellow component to the spectrum or absorb non-yellow components?
If they absorb, then why are they used in telescopes being imperfect?
If they add a ...
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How does light speed up after coming out of a glass slab?
As I learned today in school, my teacher told me that when light enters a glass slab it slows down due to the change in density and it speeds up as it goes out of the glass slab. This causes a lateral ...
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Why does paper become translucent when smeared with oil but not (so much) with water?
When I smear oil onto a scrap of paper and rub it in, the paper becomes quite translucent; but when I attempt the same with water it doesn't as much. Why?
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Why do I see better under water using swimming goggles? [duplicate]
I am myopic (I don't really know if this is relevant or not) and I usually swim without contact lenses. My vision is clearly better underwater when I am using swimming goggles.
I have tried to ...
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How can an object absorb so many wavelengths, if their energies must match an energy level transition of an electron?
I believe I have a misunderstanding of some principles, but I have not, even through quite a bit of research, been able to understand this problem.
My current understanding of transmission, ...
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