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6 views

Are there real-world examples of refraction of light due to magnetic permeability?

The question Fresnel Transmission Coefficient for Magnetic Field is interesting. Thinking about it led me to reflect upon what little I know of the history of optics, with refraction by lenses and ...
0
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1answer
17 views

Calculated focus of an asymmetric bi-convex lens

So I've been working on modeling an optical system using ray tracing. I've finally gotten to the point where I am testing things however I've come across something I'm not entirely sure of. I'm ...
16
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4answers
2k views

Reverse of diffraction

Can we arrange a practical in such a way that the dark and bright bands in diffraction grating be allowed to pass through the same slit to get the original light (i.e the incident light before ...
0
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0answers
23 views

Why frequency does not change when light passes through the denser medium? [duplicate]

as far as I noticed always people in physics have a predefined assumption that frequency is constant. whereas we know that the c is the outcom of product of wavelength and frequency. we have different ...
0
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1answer
40 views

Why does the Complex Index of Refraction take part in the Reflection?

I'm aware that in Optics, the complex index-of-refraction $\eta = n+ik$ is used, which famously leads to the reflection property at an incident angle, i.e. Fresnel's law: $$R=\frac{(n-1)^2+k^2}{(n+1)^...
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2answers
56 views

Help understanding the speed of light in media with refractive index < 1

I have read the standard explanations on this, but I still have trouble with convincing myself that information is not propagating at faster than the speed c in media of refractive index less then ...
0
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2answers
35 views

Changing Refractive Index

Is it possible that the refractive index of a material could change?if so,what are those factors and what kind of variation could they bring?
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0answers
23 views

Question about transmission of paraboloidal light waves in bi-convex lens

The question is as follows: Show that a paraboloidal wave centered at $z_1$ is converted by a lens of focal length $f$ into a paraboloidal wave centered about $z_2$, where $\frac1{z1} + \frac1{z2} ...
2
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1answer
60 views

How do I use a sunstone? How does it work?

I have acquired two pieces of Icelandic Spar (optical calcite) with surface and internal fractures that should be serviceable as sunstones. I have observed the double refraction and cancelling double ...
0
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2answers
61 views

How do we determine refractive index of a photonic crystal?

Normally, refractive index of a medium is defined as $$n=\frac c{v_\text{p}},$$ where $c$ is the speed of light in vacuum, and $v_\text{p}$ is the phase speed of light in the medium. Phase speed is ...
3
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1answer
41 views

Why does the intensity of the scattered light vary when a monochromatic laser is shined into a transparent object?

When a laser is shined into a glass ball such as this video (link) or a bottle of water (link) the light is refracted through the whole transparent body. However, the intensity of the light scattered ...
24
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3answers
4k views

Why doesn’t a normal window produce an apparent rainbow?

When light refracts in a prism it creates a rainbow. My question is, why don’t all windows or transparent objects create this dispersion, i.e. why is the refractive index dependent on frequency in a ...
-2
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1answer
82 views

(7) Will a nearsighted person who wears corrective lenses in her glasses be able to see clearly underwater when wearing those glasses? [closed]

Will a nearsighted person who wears corrective lenses in her glasses be able to see clearly underwater when wearing those glasses?
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1answer
49 views

Physical Analogs of General relativity and optics

My Prof told me today there is a 1-1 correspondence between particles in a curved space time, and optics problems in various indices of refraction, extending even as far as black holes. Does anyone ...
2
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2answers
103 views

Why does a prism refract light into a rainbow? [duplicate]

Why does a prism refract light such that the different frequencies of light “spread out”? The same goes for rainbows, why do the raindrops “spread out” the different frequencies of light?
3
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4answers
72 views

Why does frequency remain unchanged in light refraction but wavelength doesn't? [duplicate]

Since the frequency of an electromagnetic wave does not change during refraction but the velocity changes, the wavelength must therefore change. But why doesn't the frequency change in the first place?...
0
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0answers
38 views

Raytracing on convex spherical surface, where n1>n2

I'm reading my textbook and I'm trying to figure the ray tracing of a single point of this one case that the book doesn't cover. My question is, what does the ray tracing look like when we have a ...
1
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1answer
27 views

“Partial” Total Internal Reflection

Can partial TIR happen? Consider the image present in this link Here, at point D, TIR happens, but also there is transmission. Is "total" internal reflection a misnomer?
1
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1answer
22 views

Is it possible to calculate the refractive index of a gas mixture given the pressure, temperature and wavelength?

I am searching for a formula to calculate the refractive index at a specific point in a planetary atmosphere. Given are pressure, temperature, wavelength and the molecular composition of the ...
1
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0answers
32 views

Will the refractive index of a electrolyte change when chemical reaction happens?

Since polarization is the reason of refraction, then anything that changes the structure of molecule, atom, or electron will present as a change of reflection. Thus, to my understanding, chemical ...
2
votes
1answer
51 views

Photoelastic modulator vs. Acousto-optic modulator

I am trying to understand the salient differences between photoelastic modulators (PEMs) and acousto-optic modulators (AOMs). Both of these devices are based on the photoelastic effect - that is, ...
0
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1answer
40 views

How to theoretically calculate refractive index of a gas?

All the resources I've seen on calculating refractive index of gases appear to give equations with various "magic constants", i.e. the equations are fits to experimental data. But I'd like to ...
1
vote
1answer
27 views

Variation of Refractive index

We know that refractive index, for any medium, $$n=1/\sqrt{\epsilon\mu}.$$ Also, according to Cauchy's relation $$n=A+B/\lambda^2,$$ where $A$ and $B$ are constants related to the medium. ...
2
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0answers
63 views

Zebra and Donkey Watching [closed]

Suppose I have a white donkey in front of me. Say i paint black stripes on the objective of my camera lens and click a photo of it. The context of this question is that when we cover a lens ...
0
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1answer
37 views

Image formation in Ray Optics

Can a refracted ray and a reflected ray form an image( different incident rays coming from the same object, one sufferning reflection and other refraction)? What is the criteria for forming an "image"...
1
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0answers
45 views

Refractive Index in Ionized Liquid from Micro Aspect

I learned about the refractive index of gases and dense materials, which is a function of the atom number per volume, wavelength of electromagnetic wave, etc. However, what is the refractive of ...
1
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2answers
72 views

Does phase change occurs on refraction at a lens?

There is no phase change between refracted (transmitted) rays and incident rays, according to boundary conditions of electric field and magnetic field, in accordance with the Maxwell's equations and ...
0
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0answers
48 views

How does a concave lens form a virtual image?

If rays of light are diverged upon exiting a concave lens, then they have no focal point. The rays completely spread out in random directions. Like diffuse reflection(which does not form an image) So ...
0
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0answers
19 views

Different Refractive indices in Anisotropic medium

In an anisotropic medium, if we consider the dielectric tensor to be diagonal and medium is isotropic in $\mu $ or ($\mu = \mu_0$). Then from fresnel equation we get a quadratic equation in 'n' (...
0
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1answer
12 views

TIRF mycroscopy with intermediate layer of different refraction index

I`m currently experimenting with through the lens TIRF microscopy in which an additional layer is used between the glass and the sample. This 10-30 μm layer has a higher refraction index than my ...
1
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2answers
56 views

Refraction of light with destructive interference

The wavelength of light determines it's refraction in a prism. But, what if two beams of light destructively interfere as they pass through a small prism, so there is no apparent wave or wavelength ...
0
votes
1answer
21 views

Is the refractive index neglected in the standard Michelson interferometer equation: $\lambda=2d/N$

Hoping someone can help with this. It's a simple question, but I can't seem to find the answer anywhere: I'm looking at the basic Michelson interferometer experiment, where you measure the wavelength ...
0
votes
1answer
49 views

Formation of a second image due to reflection at a boundary

To determine the refractive index of a transparent plate of glass, a microscope is first focused on a tiny scratch in the upper surface, and the barrel position is recorded. Upon further lowering ...
0
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1answer
49 views

Reflection coefficient derivation

from fresnel equations we have $$r_{parallel}=\frac{n_1\cos\theta_i-n_2\cos\theta_r}{n_1\cos\theta_i+n_2\cos\theta_r}$$ $$r_{perpendicular}=\frac{n_2\cos\theta_i-n_1\cos\theta_r}{n_1\cos\theta_i+n_2\...
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0answers
29 views

The ideal shape of a plano-convex lens

What's the type of the ideal shape of a surface of a plano-convex lens to focus a parallel beam at the point? Considering the lens turned its flat side to a beam. Surely it must be aspheric: ...
2
votes
3answers
82 views

Why do prism split light at angle instead of curving it?

I assume that when light goes through matter, it doesnt really slow down, but the waveform is pushed back due to some resonance with the atoms. EDIT: Interference is probably a better word than ...
-1
votes
1answer
101 views

Which colour comes out first from a prism?

When a narrow beam of white light is incident on a triangular prism. The speed of red light is maximum and violet is of minimum, red light bends less and travels less distance as compared to violet ...
3
votes
1answer
115 views

Which of these 2 methods for calculating the focal length of a concave mirror is more accurate?

I have done an experiment to measure $f$ the focal length of a concave mirror. I have a list of 8 values for $u$ the object distance and 8 values for $v$ the corresponding image distance. I ...
2
votes
1answer
88 views

What is Snell's window?

Why is it that an underwater observer can see only a circular "window" and also can't see anything above the separating surface? Does the "window" depend on the depth?
0
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0answers
30 views

Why Ewald–Oseen extinction theorem failed to explain refraction

One way to understand the refraction of light other than Huygens–Fresnel principle is by Ewald–Oseen extinction theorem, which states that light scatters only in forward direction with a slower ...
0
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1answer
63 views

How does every ray of light or photon can follow the same Snell's law in a very random states of matter like gases and liquids?

We know that to study refraction at the interface of two media, we use Snell's law which is $$μ=\frac{\sin(i)}{\sin(r)}$$ or $$μ=c/v$$ (for vacuum as one of the media). I know this is an ...
0
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0answers
14 views

Refraction of a circular polarised wave

I'm trying to derive the expression for the fields $E_{1}$ and $E_{2}$ in terms of $n_{1}$, $n_{2}$ and $E_{0}$. Where: $E_{0}$ Is the incident field amplitude of circular polarised light $E_{1}$ Is ...
1
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0answers
42 views

Refraction on the edge of mediums

Say I have this setup : Here a light ray (in red) is incident on the point A in such a way that it is collinear with AB, and the indices of refraction are as mentioned in the figure. So my question ...
0
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0answers
33 views

How To Calculate Wavefront Error of a Lens

The wavefront describes the Optical Path Difference (OPD) of an optical system. Typically the OPD has the unit of microns. The OPD is the difference of the Optical Path Length (OPL) of an arbitrary ...
0
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0answers
41 views

What is happening to a wave at a media boundary?

Say we have a light wave going from air to plastic, refractive indexes 1 and 1.5 respectively. What exactly is happening to the properties of the wave and why? Taking wavespeed as v, frequency as f, ...
8
votes
4answers
278 views

Mathematics supporting the classical explanation of why the phase speed of light slows down in a medium

Consider the answer here by Chad Orzel which explains how a monochromatic light can slow down in a medium. He explains, You can think each of the atoms (of the medium) as being like a little dipole,...
0
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2answers
87 views

What does it mean to say that glass has refractive index 1.5?

The refractive index of a material depends on the wavelength of the light incident upon it which is why dispersion happens. When we say that glass has refractive index 1.5 which wavelength do we have ...
0
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2answers
44 views

Does TIR obeys laws of reflection?

After reaching the critical angle, do Snell's laws and laws of reflection hold good?
1
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2answers
42 views

Amplitude of wave

Does amplitude of wave changes during refraction of wave If it will changes,why? I have been searched for internet but still cannot find a complete answer
1
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2answers
104 views

light travels the fastest path of two points, how do you determine those two points?

so in this diagram from Richard Feynman's book: QED Strange Theory of Light and Mater the light takes the fastest path from S to P and the lens makes it so that there are many fastest paths that go ...