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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Source of beating phenomena of a Michelson interferometer?

I was discussing the reason why we see beating from a Michelson interferometer, and one of my friend said it 's because the light have different frequencies, therefore, they would be out of phase. ...
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95 views

What is the requirements from an optical lab in terms of darkness

I am characterizing an optical lab and would like to know therefore what are the requirement from a standard optical lab in terms of ambient luminescence. In other words how dark should an optical lab ...
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Polarized sunglasses: should the axes in both lenses be parallel?

See the pictures below. A pair of sunglasses I recently purchased has the polarization axis in one lens offset about 20 degrees (by eyeball estimation) from the other. I don't have much experience ...
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Are coherent states of light 'classical' or 'quantum'?

Coherent states of light, defined as $$|\alpha\rangle=e^{-\frac{|\alpha|^2}{2}}\sum_{n=0}^\infty \frac{\alpha^n}{\sqrt{n!}}|n\rangle $$ for a given complex number $\alpha$ and where $|n\rangle$ is a ...
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346 views

Difference in perception of unpolarized and polarized light

What is the difference in perception of polarized light and unpolarized light? What difference does polarized light cause to our eyes?
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2answers
103 views

Is it possible to build an optical system that increases the perceived surface brightness?

So is it possbile to build a system from lenses and mirrors that can make faint gas nebulas brighter or can be used as nightvision? If you increase the size of the aperture of a telescope it will ...
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2answers
682 views

Diffraction Grating Spectrometry Question [closed]

Yes, this is a homework question, but I've already failed to solve it enough times that the online system hosting it isn't going to give me any marks, so I figure it's a good time to stop hitting the ...
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3answers
2k views

Exciting Surface Plasmon-Polaritons with Grating Coupling

I'm very new the topic of SPPs and have been trying to understand this particular method of exciting surface plasmons using a 1D periodic grating of grooves, with distance $a$ between each groove. If ...
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73 views

Optics & Law of Cosines

I'm supposed to use law of cosines on $S_1S_2P$ in the following diagram that relates to a lens: To arrive at the following equation: $$ \frac{r_2}{r_1} = [1 - 2(\frac{a}{r_1})sin(\theta) + (\frac{...
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2answers
1k views

About partially polarized light and the degree of polariztion

When I was taking Optics course, I found there were several questions about polarization of light. I use the textbook of Hecht. It seems that the definition of degree of polarization may be not so ...
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1answer
575 views

Image formed in a compound light microscope

I am trying to understand whether the image formed in a compound light microscope is at infinity or not. I get conflicting answers everywhere I look.
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1answer
64 views

Determining distance from object in concave lens [closed]

so I was studying for my Yr11 Physics test tomorrow and I came across a question that I got the wrong answer on, all of my friends are getting the same answer. Question: You wish to project the image ...
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2answers
503 views

Fully destructive interference

I'm aware that this is somewhat of a frequently asked question (not only here), and i've dug through respective answer for a few hours before i decided to ask here. None of those answers helped me ...
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1answer
820 views

What gives substances their color?

As far as i know (i may be wrong!), substances appear to have a definite color because they reflect/ transmit all the light rays of the given color, and absorb all the lights rays of the remaining ...
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2answers
162 views

Why is there no dark band below a rainbow?

I've read articles about Descartes' theory of the rainbow and I can understand why there is a dark band of about 8 degrees (Alexander's band) between the primary and secondary bows: for all the water ...
3
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1answer
118 views

Michelson interferogram white light pattern symmetry

Why is the white light of the interferogram produced by using Michelson Interferometer necessarily symmetric? This is really hard to think.
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99 views

Temperature-induced wavelength shift of optical coatings?

Optical coatings designed for reflection or anti-reflection are made of many thin layers which will expand when heated. What will the effect be on the wavelengths the coating will reflect when the ...
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1answer
63 views

Nokia PureView microscope: fluorescent Imaging

I've come across this article: Fluorescent Imaging of Single Nanoparticles and Viruses on a Smart Phone. And what is the theoretical limit for such smartphone extension? And how that limit can be ...
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101 views

Why do I get different colours in scratched holograms?

I was making a scratched holograms and in result got different colours instead of white hologram
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42 views

Why do 3D holograms need curved lines?

I'm making a scratched hologram and I'm interested in we have to make curved lines to get a 3D image.
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1answer
855 views

Why does this flashlight lens have this shape?

I pulled apart a flashlight and found a similar lens as the one shown below. I assume that the light starts off as a “point source” somewhere inside and the curvature and/or shape of the “lens” ...
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1answer
708 views

Triboluminescence, how does it work? [duplicate]

I was browsing Reddit and I stumbled upon this. It is a video on making duct tape glow a blue light by pulling two pieces of duct tape apart. Appearntly the glowing is caused by something called ...
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1answer
998 views

how does the mirror equation works and what lead to using of sign convention?

EVERYTHING HERE IS FOR CONCAVE MIRROR Everywhere I see the derivation of the mirror equation is given by placing an object before the focus and then proving similarity of the triangles to get to the ...
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1answer
257 views

Experiment regarding myopic correction by a manipulation of fingers?

Here is a small experiment my tutor once told us for just amusement. It works for myopic people at least, and can be a good check to see if you have myopia. With your naked eye, ("remove the ...
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3answers
181 views

Possibility for contact lenses that enhance the vibrancy of color

Would it be possible to develop oculars that would enhance the vibrancy of color? I know there are many digital filters to improve vibrancy, but are there physical devices able to produce the same ...
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1answer
37 views

Fluorescence lifetime imaging [closed]

Actually I am not a physics student but I have to give a lecture about Fluorescence lifetime imaging(FLIM). I am thinking of comparing this techniques to another imaging techniques. Does anyone know ...
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2answers
579 views

How to determine if a optical system is afocal?

I have to come up with a method to measure the focal length of a concave lens that's not in my lab guidebook. So I decide that I will build an afocal system with a convex lens and a concave lens and ...
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334 views

Dispersion relation of silicon

In the case of dispersion relation of silicon having crystal plane orientation 111; what is the Sellmeier's equation for refractive index $n$ of silicon orientation 111 & what it's extinction ...
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1answer
729 views

Problem in Youngs double slit experiment

This is from Young Double slit experiment. But How to prove the the two $\theta$ are equal, I meant, how $\angle EAD= \angle PEC$? I see from the both triangle have $90^0$ but what about others?
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6answers
955 views

Is antumbra part of shadow darker than penumbra part of shadow?

I'm exploring different types of shadows casted by objects. I want to know if antumbra part of a shadow is darker than penumbra part. I've found two misleading pictures on Wikipedia: First: Second: ...
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2answers
137 views

High power beam splitting

I'm trying to split a high power laser (1064nm, 20W, beam diameter @ 1/e^2 intensity: 3.2mm) into two beams and couple them after some additional optics into two SMF's (single mode fiber). So far I ...
2
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2answers
811 views

Lambert's cosine law

I am learning how to physically render images in computer graphics. I just saw that the area that gets light is given by the Lambert's cosine law. In my head it makes perfect sense the relation but ...
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8answers
960 views

Is there a lens that would invert my vision?

Would I be able to invert my vision by mounting a particular lens in front of each eye? I am currently able to achieve this by mounting a right-angled triangular prism across both eyes. The specific ...
60
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3answers
25k views

Why can we see the dust particles in a narrow beam of light (and not in an all lighted area)?

Let us say that I am sitting in a room with all the drapes open. Bright sunlight is coming through the window. The whole room is brilliantly lighted. I will not be able to see the dust particles ...
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0answers
55 views

When viewed from a telescope, does an object get more magnified if its angular diameter is increased?

and if yes, how can the diameter be increased? Lets say I want to view saturn from a small telescope. Increasing the angular diameter will give a better magnification if the answer to the above ...
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1answer
65 views

Determining the limits of an integral

In Griffiths' Introduction to Electrodynamics, Problem 1.28 (the triangular prism question) is especially challenging for me. I do not know how the limits of x are 0 to (1-y). My concern is the ...
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2answers
200 views

Length of solid part of object shadow

Little background first: I take part in preparing environmental reports for wind turbines/farms and now I'm exploring shadow flickering effect of moving blades. From some sources (in Polish) I got ...
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3answers
508 views

What electric field vector should I use for modeling unpolarized light?

Regardless of computational cost, light is a kind of electromagnetic wave, so it can be simulated with Maxwell's equations. If we want to simulate light with Maxwell's equations, we need to express ...
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2answers
510 views

How to test cutoff frequency of IR filter on camera?

Modern cell phones seems to come with IR filters on their cameras. I want to do an experiment to figure out what wavelengths these filters allow to pass and which they block. How would I go about ...
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1answer
2k views

conceptual meaning of “virtual image” [duplicate]

I am trying to learn about optics and I am having a hard time understanding the meaning of "real" vs "virtual" image. My understanding is that for a concave mirror, the image focuses on the same side ...
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4answers
550 views

Thin lens formula

Can someone help me or guide me how the thin lens formula: $$\frac{1}{s_1}+\frac{1}{s_0}=\frac{1}{f}$$ can be proven? I was trying to prove it on my own using similar triangles, only to fail.
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1answer
292 views

Infinite Mirror Face to Face With Infinite Two Way Mirror

If you are in deep space, and there is an infinite plane mirror, and in front of it there is another infinite mirror that is two way, with the see through side towards you, what do you see? Is it the ...
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265 views

How does light pass through rough glass?

Light incident on a rough surface will be diffuse after passing it. Angular intensity depends on the grinding of the glass surface. I'm trying to find information about the scattering indicatrix of ...
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2answers
5k views

Why would an object appear a different size when in water?

A friend of mine has a homework question and we're having some trouble figuring out what physical mechanisms come into play for this. An underwater swimmer sees a spherical air bubble that appears ...
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1answer
198 views

does the beam of a laser have 'throw'?

I was thinking about Einstein's train and platform experiment and was wondering if a beam of light experiences throw? Let me explain, if I take a water hose and point it straight out and then swing ...
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2answers
4k views

Why does aperture size affect depth of field in photography?

Why do small and big holes (the aperture) in a lens change the depth of field in the image? (if you have big hole you have smaller depth of field). I wondered if I should ask this on photo....
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1answer
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Explanation of photon reflection [duplicate]

What occurs in atomic scale that cause the photon to be reflected? In other words, what is the reason for photons to change its direction and why material can reflect certain wavelengths and absorb ...
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2answers
368 views

Refraction of light in medium

Given that the plane $y=0$ separates the vacuum ($y>0$) from the optical medium ($y<0$), I would like to calculate the trajectory of a light ray starting at the point $(x_1,y_1)$ and ending in $(...
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1answer
341 views

Is it possible for a material to shift the frequency of all light reflected off of it by a specific and constant value

Without reducing the energy more than necessary due to the frequency decrease? And if this happens/works, is there an index of such materials and their optic properties?
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Explain reflection laws at the atomic level

The "equal angles" law of refection on a flat mirror is a macroscopic phenomenon. To put it in anthropomorphic terms, how do individual photons know the orientation of the mirror so as to bounce off ...