0
votes
1answer
32 views

Why do roads appear wet on hot days? I do not understand [duplicate]

Why do roads appear wet on hot days? I don't understand the bending of light rays in relation to the density fluctuations. How are they related? Why do we see mirror images of cars on road in hot ...
1
vote
0answers
17 views

Phase shift in back-reflection generated at the mating point of two fibers

If you have light traveling from glass to air at normal incidence, e.g., in an optical fiber with the endface open, the Fresnel reflection coefficient would roughly be $R = |(1.5-1)/(1.5+1)|^2 = 0.04$ ...
0
votes
2answers
60 views

Light-Matter Interaction and Object's Appearance

I am taking a course in Computer Graphics, and the teacher said we could put materials in there main categories: mirror like glossy or specular diffuse He suggested that the law of reflection is ...
2
votes
1answer
70 views

A mirror in the sky to look at past Earth

Earth reflects light from Sun into Space; are there any "mirror like" objects which reflect back to Earth this light? Has anyone been able to use this method to recover some information on how was the ...
-1
votes
1answer
35 views

Can we multiply an electromagnetic field?

can we multiply light by a sequence of reflections in a closed vessel? also, is light a part of EM wave? can we multiply the radio wave or EM wave from a transformer?
2
votes
2answers
45 views

does the positon of the virtual image change when I change position?

I placed a box in front of a plane mirror I looked at the image and smudged a bit of Vaseline on the mirror as a mark to indicate where I thought where the virtual image was. After that, I ...
1
vote
1answer
37 views

Increase contrast on the image taken by CCD camera

I project a pattern on a reflecting object and I capture the reflected pattern (reflected via the object) using a CCD camera. However, the reflected pattern has a very low contrast (due to volume ...
-2
votes
0answers
49 views
0
votes
1answer
41 views

Drawing Ray diagrams

When drawing ray diagrams for concave mirrors, I was advised to : draw a ray that is parallel to the principle axis, the reflected ray will pass through the focus Draw a ray through the center (C), ...
13
votes
2answers
2k views

Is it possible to 3D print a mirror to create a high quality telescope?

Is it possible to 3D print a mirror with todays available materials? If so, would there be a reduction in image quality?
2
votes
1answer
51 views

Reflection from multiple thin films: accounting for lost light due to small surface area

I have a problem similar to reflection of multiple thin films. I have light coming in from medium 1 and I want to find the total reflected intensity after being reflected inside 2 layers. However, I ...
5
votes
2answers
319 views

How would an X-ray mirror work?

I was wondering if light can be reflected how can someone reflect X-ray of what material does it need to be made of and is its design completely different to that of our original mirrors? Does this ...
1
vote
3answers
103 views

Can light be trapped theoretically?

My question is a little silly I know, but I'm curious to know if a particle of light can be theoretically trapped between two reflective screens. For example once the particle of light has left it's ...
2
votes
1answer
54 views

Total internal reflection and waveguides

I'm looking at a model of a planar dielectric waveguide along the lines of this picture: For the wave inside the $n_1$ dielectric slab to totally internally reflect $\theta_M$ needs to be smaller ...
1
vote
1answer
66 views

Anti-reflective coating effect on total internal reflection?

If the surface of prism is coated with an anti-reflective coating, (specifically an index matching, refractive index gradient, or moth-eye structure), and light impinges at a greater than critical ...
4
votes
0answers
185 views

The physics behind Google Glass' “prism”

In writing a bachelor's thesis about applicable use cases for Google Glass in retail I also strive to explain the physics behind Glass' optics. So far I've come to the following conclusions: Glass ...
0
votes
2answers
65 views

Image formation at surface of water

Consider a lake full of water which has an object immersed in it. Now, if an observer was at the surface at a sufficient distance so that the light ray from the object is internally reflected, should ...
6
votes
3answers
850 views

reflection at intersection of 2 mirrors

Consider 2 mirrors which intersect at an angle. If we draw a light ray intersecting the mirrors at their point of intersection, how will it reflect? What will be the normal at that point?
3
votes
1answer
59 views

Differences between absorption, transparency, reflection, and emission

Can someone help me conceptualize the differences between a photon's involvement with absorption, transparency, reflection, and emission? To be more specific, my current understanding of the matter ...
3
votes
1answer
70 views

Why does silver have such a strong UV resonance compared to other metals?

Related: Why did high quality mirrors use aluminum coatings instead of silver? After reading Chris White’s and LDC3’s comments in the above related link, it got me wondering about silver’s atomic ...
20
votes
6answers
2k views

Why did high quality mirrors use aluminum coatings instead of silver?

I have two questions on mirrors. I’ve read that in the past quality mirrors were coated with silver but that today vacuum evaporated coatings of aluminum are the accepted standard. When I look at ...
1
vote
1answer
47 views

Reflections in a double-glazed window

Recently I observed reflections in a double-glazed window. I wondered that the double reflections were not the same if I changed my point of view. For example the two images of a candle would overlap ...
4
votes
2answers
143 views

Is a Perfect/Lossless Mirror possible?

In traditional mirrors, some of the input light is absorbed by atoms in the mirrors surface and are 'lost' as heat, degrading the quality of the reflected image. Could this loss be compensated by an ...
2
votes
2answers
109 views

Anodized aluminium reflectivity at 10.6 um

I wonder how I can model anodized aluminium reflectivity in ray tracing-based optical simulation. I know that the parts my company is using are anodized to get covered with a ~20 um (as specified) ...
10
votes
2answers
351 views

a wierd image of sun

Have you ever notice the sunset's image in the sea? It's like long light path to the end of the horizon! I've attached a sample of this: How can we explain this? I know that it can happen even in ...
1
vote
0answers
40 views

Beamsplitter and Dielectric Mirror

Among two optical components. One is a Nd:YAG Laser 50/50 Beamsplitter and the second one is a Dielectric Mirror see pictures. Both of them almost looks like the same. If the specification is not ...
0
votes
2answers
79 views

Layer thickness measurement

I am interested to measure the thickness of the coating on a mirror (e.g. in the picture below). What are the available and best way of measuring it? What will be the solution in case of multiple ...
1
vote
0answers
111 views

What is the effect of total internal reflection on polarized light [closed]

Total Internal Reflection causes phase change of a light beam. I searched for effect on a polarized light beam by Total Internal Reflection but could not find much. I am assuming polarization does not ...
0
votes
0answers
78 views

Difference between the increase in optical path due to refraction and that due to reflection

If we place two glass plates of refractive index n and each having thickness t,on the way of a light ray the increase in optical path becomes (S2P-S1P)=2(n-1)t due to refraction through them,and the ...
14
votes
2answers
566 views

Would you see a rainbow from refraction when the sun is in front of you?

I know how rainbows are formed, and why. Usually it is said that the Sun must be behind the observer, in order for its light to be totally reflected inside the droplet and then reach the observer. ...
0
votes
0answers
67 views

How to demonstrate total internal reflection?

How can we demonstrate total internal reflection practically to explain it clearly?
0
votes
0answers
36 views

Would electron degenerate matter be a good x-ray reflector?

I do not know much about x-ray physics or degenerate matter, but I have the intuitive feeling that the high electron density and what must be some crazy band structures in electron degenerate matter ...
1
vote
1answer
109 views

What really is reflection? [duplicate]

What really is reflection? Is it just the reemission of EMR? I asked my teacher, he said in quantum sense, it is true. But when I read something about emissivity in Stefan Boltzmann's equation, it ...
3
votes
2answers
744 views

Fermat's principle to prove the law of reflection

Fermat's principle tells that a light ray will follow a path from point $A$ to point $B$ so that the optical path length of this path is an extremum over neighboring paths. I wanted to use this ...
2
votes
0answers
43 views

Relection of light [duplicate]

If I recall my physics correctly, and it was a long time ago, when a photon strikes a reflecting surface that specific photon is not what is reflected--rather the photon excites an electron which ...
0
votes
1answer
74 views

What Material for reflective surface of a solar grill/barbecue? [closed]

I have been planning on building a solar grill for quite a time now, and the one problem, which is also the biggest - I need to shape a mirror into a paraboloid, so it bundles solar energy ...
1
vote
1answer
146 views

Why is a rainbow curved in shape?

Why is a rainbow curved in shape? When dispersion of light takes place, light splits into seven colors, but when rainbow is formed it appear to be bent. Why does this happen even though light travels ...
3
votes
1answer
70 views

Can a full image be made in mirror if we change the distance between object and mirror?

To see the full height of man, the height of mirror should be half of the height of the man. What happens when we decrease the distance between mirror and man?
2
votes
3answers
102 views

Clear vs black in terms of light reflection?

I've heard that clear things such as the gaseous components of the atmosphere or water reflect no light, and that is why they are clear. I've also heard that black things such as asphalt are such ...
2
votes
2answers
96 views

What really makes a rainbow happen?

Yes, a rainbow is formed when a raindrop refracts light, but why then does the whole sky not become a huge rainbow when it rains? Would the light not be dispersed into ordinary 'white' light? What ...
0
votes
0answers
101 views

Bragg's law in photonic crystals

So in photonic crystals when looking at diffraction the refraction of light has to be taken into account. I am told this would lead to the "photonic bragg's law" which is $$n \lambda = ...
2
votes
3answers
211 views

During reflection does the emitted photon have same properties?

When light (photon) is reflected the the original photon is absorbed by an electron and then emitted again. Does this "new" photon have the same wavelength, frequency etc. as the original?
0
votes
1answer
293 views

Imaginary part of Poynting vector

When I am studying the total reflection phenomenon, I calculated the Poynting vector of the transmitted wave, which can be written as $S_t=A(k_{x}\hat{x}+i\alpha\hat{z})$ A is some constant. I ...
1
vote
3answers
285 views

Mirrors into Infinity [duplicate]

Could someone please name the phenomenon regarding the stretch of reflections into infinity between two opposing mirrors, and also explain why the reflections curve away instead of meeting at a ...
0
votes
2answers
2k views

What are virtual objects, Reflection of light? [duplicate]

While studying reflection through a plane mirror, I have been told that when the object is real the image will be virtual and the image will be real while the object is virtual. What are virtual ...
2
votes
1answer
99 views

How does one calculate the polarization state of random light after total internal reflection

How does one calculate the polarization state of random light after having been totally reflected by a single dielectric interface? Please consider pure specular reflexions from a plane interface ...
5
votes
1answer
61 views

Capture reflecting image

Suppose you have following installation: ...
1
vote
2answers
206 views

Reflection between two mirrors?

If I put my hand between two perfectly aligned mirrors and then remove it will the images continue to reflect for a few nanoseconds? If yes then will the images be of a combination of the front and ...
3
votes
2answers
107 views

Is it possible to focus the sun in such way?

Imagine the sliding part of the mirror is controlled by computer and opens on intervals. Is it possible to increase the power of the beam by making it bounce between the mirrors thus going through ...
3
votes
2answers
310 views

The Goos Hanchen shift mechanism

When the light is totally reflected in the interface between dense and less-dense medium, we know that the reflected beam will shift a little. Currently I have known the reflection coef r, will be a ...