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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Can Incoherent Polarization Beam Combining be Used to Produce Polarized Light?

I know that different beams can be incoherently combined to produce high power laser sources. But as far as I know these resultant beams are not polarized. But what if you combined several lasers with ...
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1answer
90 views

How fast would you have to run to create a mirror image?

So I was watching The Flash and in the most recent episode he runs so fast that he is able to create a mirror image of himself so that it looks like there is more of him than there actually is. So I ...
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49 views

Dispersion in ultrafast lasers

In mode-locked Ti:sapphire lasers, positive dispersion is caused mainly by the crystal. A prism pair placed in the laser resonator can compensate for some of the dispersion by introducing negative ...
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27 views

The squeezed-displaced-thermal state [closed]

I wonder whether the following squeezed-displaced-thermal state has any applications in the related fields. I would be grateful if anyone could make some comments.
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1k views

How can a slowed light ray bend?

If light is traveling through air, it slows down and ends up bending. But how? If I'm running straight, and I get slowed down, shouldn't I still be running straight?
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39 views

Fraunhofer diffraction at circular aperture - integration of bessel function

I'm trying to understand the calculation here: http://en.wikipedia.org/wiki/Fraunhofer_diffraction_(mathematics)#Circular_aperture for the solution by integration, but I plain and simple fail to see ...
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38 views

Interference of light in a dielectric mirror

Here it is mentioned that for dielectric mirrors (mirrors designed to reflect a specific wavelength of light) "there is a 180-degree difference in phase shift at a low-to-high index boundary, compared ...
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1answer
33 views

Is an iPad screen an Optical Prism?

One day, I noticed that sometimes, when there is an iPad right below a light, such as a chandelier, when viewed from an angle, one can see what looks like a spectra of colors. Is the iPad screen ...
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66 views

I have some questions about reproducing Young's double slit experiment

I want to reproduce Young's double slit experiment for a school project. For the slits I am thinking making cuts in aluminium foil or maybe do something with pencil leads like this instructable ...
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33 views

Is Snell's Law valid even for on any curved surfaces?

Proof of Snell's Law can also done by using Fermat's principle of least time on plane surfaces. Can we prove the same result for any curved surfaces ?
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38 views

Calculating propagation time along the path of a photon

In this paper $\tau(t) := \int_{t}^{t_d}ds$ is defined as "the propagation time between the detection time, $t_d$, and $t$, as incrementally measured by a set of local observers along the light path". ...
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16 views

Hollow metallic waveguides versus optical waveguides versus cables

In almost every physics program, you learn about electricity, electromagnetism, photonics, ... Within the electricity course, you learn about transporting electric energy as electrons through cables. ...
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71 views

Refractive index of prism

The formula for the refractive index of a prism is: $$\mu = \frac{\sin (\frac{A + D_m}{2})}{\sin (A/2)}$$ However, this requires me to find out the angle of minimum deviation ($D_m$). This would ...
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19 views

Which coefficients are needed to numerically obtain transmission spectrum?

I'm using Omnisim program. I would like to obtain transmission spectrum of certain material so I have created two polynomials: one representing real refraction coefficient and one representing ...
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44 views

Formula for intensity and central bright fringe in Fraunhoffer diffraction from single slit

I want to understand why, theoretically, the central bright fringe has maximum brightness/intensity. And where does the formula $I=I_0\left(\frac{\sin B/2}{B/2}\right)^2$ come from? My book says it is ...
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1answer
45 views

Shack Hartmann lenslet array design

What is the relationship between the number of pixels on a CCD that are dedicated to a lenslet array and the number of pixels covered by the focal spot from one lenslet array on the CCD? Specifically ...
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3answers
350 views

Why does a ray passing through optical centre remain undeviated?

How can it be explained using the laws of refraction that a light through optical centre of a lens passes undeviated? If we assume the portion of the lens in the middle to be made of even number of ...
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88 views

Refractive index and color

Does the color of an object have anything to do with its refractive index, and if so, what is the relation? I tried googling this and searching through the questions on stack exchange, but I haven't ...
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1answer
79 views

Single Slit Diffraction

I am trying to derive the intensity variation function for a single slit diffraction. Sorry for the poor diagram... So I decided to take the amplitudes of the waves originating from the slit on the ...
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30 views

How the malus law will be changed for the averaged intensity

If a polarized beam of light passes through an polarizer then, the intensity of the output polarized light obey Malus law. $$I =I_0 \cos^2 \phi$$ Now if we rotate the the polarizer with an ...
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49 views

Easy method to measure the NA of a lens system?

I have a lens system made up of some components of the Leica Z16 APO zoom system. This includes a built-in iris diaphragm to adjust the Numerical Aperture (NA) and therefore the depth-of-field (DOF). ...
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1answer
79 views

Why is it desired to have an aperture of a spherical mirror to be less than the radius of curvature?

In many instances, I have noticed that it is given that the aperture is less than the radius of curvature for a spherical mirror. Why is this given like that?
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41 views

Which waveguide mode will be excited by circularly polarized laser mode $\mathrm{TEM}_{00}$ entering hollow fiber?

Linearly polarized Gaussian mode $\mathrm{TEM}_{00}$ mode, would couple into HE modes of circular hollow fiber. Which modes would circular polarized beam excite entering hollow circular fiber ?
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54 views

Defining charateristic of light wave?

"Light is refracted when it travels from one medium to another." Does the sentence show that light is a wave?
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43 views

How do chirped mirrors compensate dispersion?

How do chirped mirrors compensate dispersion? I understand that if you have longer wavelengths penetrating deeper into a chirped Bragg stack, then there will be some anomalous dispersion because the ...
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27 views

Polarizing cavity dumped laser light

From what I have read, most lasers are polarized because of Brewster windows. However, cavity dumped laser light never interacts with Brewster windows. Now, I know that there have been many cases of ...
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1answer
39 views

Coherent Polarization Beam Combination

All the papers I have read regarding coherent polarization beam combination split laser beams and then coherently combine the components. But is it possible to coherently combine two different lasers ...
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38 views

Refraction under water

I have difficulties visualizing following task A diver is $d = 10 m$ below the water surface ($n_{water} = 1.33$). What is the diameter of the circle through which the diver can see the sky? ...
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25 views

Nature of components of two unpolarized lasers with the same characteristics

From what I understand, unpolarized laser light is composed of two orthogonal components with different frequencies. Thus, since there is not definite phase relationship between the components, the ...
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28 views

What are the physics principles behind “amphibious” camera lens windows?

Underwater camera housings have a window through which the lens looks. When the camera surfaces, a couple of things can happen, and I've seen both captured in the camera footage. In one case, water ...
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1answer
46 views

Optics - how a lens distorts the image

If we consider a small object of length $b$ that is placed flat along the axis of a concave mirror, how will the image produced be different from the object? I know that a lens will magnify or ...
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1answer
45 views

does the Fresnel approximation apply in the far field?

Most sources I've looked at treat far field diffraction and near field diffraction as separate cases, with the former using the Fraunhofer approximation and the latter the Fresnel approximation. In ...
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204 views

Should a superconductor act as a perfect mirror?

I have been told that metals are good reflectors because they are good conductors. Since Electric fields in conductors cause the electrons to move until they cancel out the field, there really can't ...
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44 views

Trapping force in optical tweezer

I am reading a paper on theory of optical tweezers in ray optics regime by A. Ashkin. For reference "click here". It is given that Gradient force $F_g$ is directed perpendicular to the light ray and ...
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31 views

Is Rayleigh/Wood's anomaly simply the grazing order diffraction?

Is Rayleigh/Wood's anomaly simply the grazing order diffraction? I read some related papers but I am still confused, can I simply understand it as a surface wave propagating on the surface because of ...
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25 views

Method of Transformed Impedances

So I am taking an advanced optics class at the moment, using the book Lasers and Electro-Optics by Chris Davis. At one point, while explaining the concept of impedance, he mentions something called ...
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43 views

The properties of light photons [duplicate]

Please consider a closed room with light reflecting walls and in the centre of the room there is a Lighting Bulb. Now if I switch on the bulb, the room is obviously illuminated with light. When I ...
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1answer
33 views

What techniques are used in the Analyzer part of an Ellipsometer?

Specifically, what technique is used where the analyzer does not involve mechanical rotation? I assume it is a device to electronically rotate the plane of polarization of incoming light. Faraday ...
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23 views

LED characteristics to use in heating a material sample?

I am looking to be able to heat a sample of material, typically less than 500mg and sitting in a fused silica sample holder about 10mm diameter. Wondering about using (say) a 5W LED with narrow ...
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13 views

What is A2L refractive index polynomial?

I'm working with a photonic modelling software and in the manual I saw that I can specify refractive index of modelled material with following polynomial: ...
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2answers
32 views

Does the ray transfer matrix for a gap change, based on the index of refraction of the medium?

The ray transfer matrix for a gap is typically: $$\begin{bmatrix} 1 & d \\ 0 & 1\\ \end{bmatrix}$$ If I know that my glass is a thickness $L$ does the ray of light that goes into it travel a ...
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4answers
161 views

Shining a laser onto a mirror

Theoretically, if I shined a laser at a mirror at an angle of 0 degrees so that the light was perfectly reflected back to the light source, then I should not be able to see the light because it is not ...
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2answers
118 views

GRE practice: Total internal reflection question [closed]

Hi, I am having a lot of troubling figuring out how to solve this problem. Equations: Snell's law leads to a total internal reflection equation $$\theta_c = \sin^{-1}(1/n).$$ This angle corresponds ...
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1answer
84 views

Would a camera that only takes light at 90 degrees work?

From what I understand cameras and biological eyes work in a similar fashion, they all take light in a cone and distances are perceived as the angle which the object takes up rather than it's physical ...
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1answer
117 views

How to interpret the complex index of refraction?

The index of refraction which represents how much light gets refracted when entering a medium is defined as $$n = \frac{c}{v}$$ I have seen it stated in several places, such as here, that we can ...
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23 views

About index ellipsoid

I wonder why the displacement field $\mathbf{D}$ at a normal mode are parallel to the major and minor axis of the ellipse which is the intersection of index ellipsoid and plane orthogonal to the ...
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20 views

What shape lens would allow correct image projection at an oblique angle? (anamorphic)

If you wanted to project a slide projector's image on a table as opposed to the wall and you could not move, shift or tilt the components. Just able to change the lens. What would the lens ...
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1answer
55 views

What is the physical explanation of Fresnel's equation?

When EM radiation is travelling between the media of different refractive indices, parts of it are reflected and transmitted according to Fresnel's equations. The amount of reflectivity and ...
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1answer
194 views

Why is $\textbf{D}$ the response to $\textbf{E}$?

In the text Wooten, equation 2.69 shows $\textbf{D}$ being the response to $\textbf{E}$ with $\epsilon$ as the response function: $$ \textbf{D}(\textbf{r},t) = \int d\textbf{r}^{\prime} \int ...
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27 views

How can slightly elliptically polarized light pass through a polarizer set to pass linearly polarized light?

How can slightly elliptically polarized light pass through a polarizer set to pass linearly polarized light? And what will be the corresponding change in intensity?