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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Why does the sky change color? Why is the sky blue during the day, red during sunrise/set and black during the night?
Why does the sky change color? Why is the sky blue during the day, red during sunrise/set and black during the night?
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How are classical optics phenomena explained in QED (Snell's law)?
How is the following classical optics phenomenon explained in quantum electrodynamics?
Reflection and Refraction
Are they simply due to photons being absorbed and re-emitted? How do we get to Snell'...
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How is it possible there are UV photos while our eyes cannot detect UV waves?
I know this question sounds dumb, but please bear with me. This question came into my mind while I was looking at the photos in an astronomy book. How is it possible that IR and UV photos of stars and ...
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If a lens focuses all incoming light to a point, how do we get 2D images?
How do lenses produce 2-dimensional images, if a lens bends all incoming rays of light to intersect at the focal point? Shouldn't this produce a single dot of light on a screen placed at the focal ...
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What causes this pattern of sunlight reflected off a table leg?
My friend noticed an interference-like pattern around the table leg. However, we do know that interference patterns of sunlight produces rainbow colours. What seems to be happening here?
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Does a "capacitor" for light exist, which could filter out flickering?
If I have a light that is flickering at a frequency low enough to be perceived by the human eye, is there any type of material that exists that will smooth out the appearance of flickering? Similar to ...
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Do people wearing glasses have different field of view than those who don't?
There is one thing I sometimes wonder about ever since I was a child.
Do people who wear eye glasses see objects in different size than those who don't?(Technically different size means different ...
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Does pure yellow exist in variations we can't discern? [duplicate]
If you add red light (~440 THz) and green light (~560 THz), you get what we perceive as yellow light (~520 THz). But I assume what you really get is a mixed waveform that we perceive as yellow? ...
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Did NIST fudge this news story about absolute zero?
This press release by NIST, titled "NIST Physicists ‘Squeeze’ Light to Cool Microscopic Drum Below Quantum Limit", makes the following claim:
The new technique theoretically could be used to cool ...
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How does Fermat's principle make light choose a straight path over a short path?
This is a thought experiment where I have made a "C" shaped hole inside diamond. The refractive index $(\mu)$ of diamond is 2.45. Say we shine a laser from top of the "C" as shown.
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How do Optically Active Compounds Rotate Plane Polarized Light?
I am not sure if this is more of a Chemistry or a Physics question, but in my Organic Chem class we discussed that chiral molecules will rotate plane polarized light. However, my professor did not ...
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Virtual vs Real image
I'm doing magnification and lens in class currently, and I really don't get why virtual and real images are called what they are.
A virtual image occurs the object is less than the focal length of ...
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Why can adding more polarization filters increase the amount of light that goes through them?
I am having some difficulty accepting the implications of the equation governing the intensity of light passing through polarization filters,
$$ I = I_0 \space\cos^2\theta $$
with $\theta$ being the ...
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How does gravitational lensing account for Einstein's Cross?
Einstein's Cross has been attributed to gravitational lensing. However, most examples of gravitational lensing are crescents known as Einstein's rings. I can easily understand the rings and crescents, ...
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Why does a mirror reflect visible light but not gamma rays?
Visible light (~500 THz) as well as gamma rays (~100 EHz) are electromagnetic radiation but we can reflect visible light using a glass mirror but not gamma rays. Why is that?
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