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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projective camera: back-projecting a point on the image plane into 3-space

suppose I got a projective camera model. for this model I would like to back-project a ray through a point in the image plane. I know that the equation for this is the following: $$ y(\lambda) = P^+ ...
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1answer
498 views

Origins of the principle of least time in classical mechanics

Is it possible to derive the principle of least time from the principle of least action in lagrangian or hamiltonian mechanics? Or is Fermat's principle more fundamental than the principle of least ...
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1answer
697 views

Does a perfect mirror behave the same as a blackbody radiator?

If I put a perfect mirror(i.e. reflects with no attenuation) next to a blackbody radiator its spectra should be the same as the blackbody radiator. Looking only at the spectra - is there any ...
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1answer
269 views

Is there a known optical design for a beam compressor?

With my little knowledge of optics I have come across some 'known' designs such as the Double Gauss for example, is there a 'beam compressor'. My requirements are to reduce an incoming parallel ...
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1answer
152 views

Why (infra-)red light is not used in diagnostics?

I noticed that human body conducts red visible light quite well. A hand placed over a powerful red lamp seems to be semi-transparent while over any other color it does not. Possibly the light ...
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2answers
3k views

Wavelength dependent refractive index

I read in a book about optical fibers that the different spectral components of a light pulse transmitted in the fiber propagate with different velocities due to a wavelength dependent refractive ...
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1answer
93 views

What means: distortion <XX% in lens spec?

I'm going to buy a lens and I would like to understand what means "distortion < XX%"? It's a vari-focal 10-60mm lens and mentionned distortion <12-1%. According to my understanding @ 10mm focal ...
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1answer
1k views

How to read a lens spot diagram?

I would like to get an explanation on how to understand such a lens spot diagram: Thanks
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2answers
1k views

Hartmann mask based collimation

Is there a detailed description for a Hartmann mask based collimation process? I've been told by a friend that is possible to collimate an SCT by placing a three round holes Hartmann mask at the ...
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1answer
599 views

Calculating Fraunhofer diffraction patterns

How does one calculate the Fraunhofer diffraction pattern for the following arrangement of slits: |...|...........|...| ..a.....3a......a (Four slits arranged linearly, spaced a distance a, 3a and ...
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3answers
142 views

Quality loss when adding more components to a telescope?

I would think this would be inherently true, but I'm curious: (Assuming the highest quality amateur instruments are used.) Is quality lost when, say, adding a T-mount adapter, diagonal or any other ...
4
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1answer
84 views

Should I be concerned about spot corrosion on a telescope's primary mirror?

I am considering buying a telescope with a large primary mirror that is about seven years old - it has a small spot of corrosion on the mirror, that the owner says is stable. Should I be concerned ...
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4answers
2k views

Is one way glass possible?

I am not talking about mirrors, just a plain window made of glass like material. Would it be possible to allow light pass only in one direction but not the other?
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1k views

Complex numbers in optics

I have recently studied optics. But I feel having missed something important: how can amplitudes of light waves be complex numbers?
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2answers
665 views

Why is the observed signal the convolution of the true signal with the instrumental function?

Imagine we are observing a star. The light coming from a star enters an optical instrument that will give us some observed data, such as the spectrum of light say. What we observe is not the true ...
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1answer
488 views

Why is the diffraction pattern for an annular aperture the difference of the two Bessel functions?

Inspired by this question, the pattern for the annular intensity is given by the square of the difference of the two Bessel functions. I would have thought the sum was more appropriate, could someone ...
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1answer
75 views

How to determine the angle a camera has to be at to image a desired scene, given the camera parameters?

Reviewing old material I learned years ago, having a hard time rewrapping my head around the relationships in capturing images from a camera. Imagine a scenario with the camera placed on the ground ...
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1answer
221 views

How does the focal length of the lens change the distance from the camera to an object?

I am reviewing some old image processing notes and have the following problem: I have a camera with a projection plane of $2cm\ by\ 2cm$ and a $15mm$ lens. If you want an $1.5m$ object to take ...
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1answer
618 views

Focusing laser & off-axis illumination & diffraction limit

I've thought I had a good understanding how resolution enhancement tricks works for projection lithography, until I tried to understand if it's possible to get sub-diffraction performance for focused ...
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1answer
2k views

How to determine the field of view for a pinhole camera with given parameters?

I am reviewing some old material I learned years ago and am having trouble figuring this one out. Can somebody confirm that I have done my math correctly, and tell me how I can recover the field of ...
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1answer
195 views

Is reflection just a particular case of scattering?

I was talking to a colleague about optical scattering from a metallic nanoparticle, and we had a very simple doubt. If you have a particle that's small compared to the illuminated area, you can use ...
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1answer
548 views

How do I get the focal length from a camera matrix?

Given the camera matrix, can I find the focal length of this camera ?
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2answers
327 views

What material can a lens be made from?

I need to make a camera lens that can easily withstand temperatures of about 1000 Fahrenheit. What should I make the lens out of?
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4answers
1k views

Is there a limit to the resolving power of a mirror telescope?

Like, if you hammered out the asteroid 16 Psyche into a 1 mm thick iron foil disc telescope mirror with 2.4x the radius of the Sun, could you resolve details on the surface of an exoplanet? At what ...
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3answers
2k views

How to calculate the temperature of a receiving point from concentrated solar power?

I'm exploring a DIY project about solar power and have found very few resources that can explain, in a not too simple but not too advanced way, how to go about calculating important values in solar ...
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0answers
424 views

how does phase-shifting principle in interferometry work?

I have been using the coherence scanning interferometry (or also known as white light scanner), where it collects images containing the fringes. The system is able to produce the depth profile for one ...
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0answers
197 views

Is it possible to calculate the work function of a metal with basic lab equipment?

ive been given a problem in physics, its to prove if a lump of metal we have been given is real gold or not. one way to to do it would be to work out its density, which is fairly easy, mass/volume. ...
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2answers
212 views

Intensity loss due to vignetting

I was trying to get an expression for the loss of intensity due to vignetting in a simple optical system, and got a fairly complex integral. I was wondering if there's an easier way, or any book that ...
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1answer
221 views

Nonlinear absorption coefficient and the band gap

How does the nonlinear absorption coefficient depend on the band gap? How can that coefficient be calculated theoretically? (Preferably with an example)
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1answer
222 views

What sets the resolution on analog film?

When taking a picture with old fashioned film what sets the resolution of the picture? Is it the wavelength, or the chemical makeup of the film?
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3answers
76 views

Operator norm directly from phase space representation of photonic quantum operator

I'm interested in calculating the operator norm of a Hermitian operator, say $B$, acting on the Hilbert space of square integrable functions. The context is I have an optical system in all its ...
2
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1answer
401 views

Transparent boundary condition [closed]

I am interested in the finite-difference beam propagation method and its applications. I try to solve the Helmholtz equation. At first, i would like to solve numerically it for the easiest case, ...
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1answer
180 views

Reflected optical rotation of polarised light

Assume polarised light travels through an optically active medium (e.g. water with lots of sugar) with the specific angle $\alpha_s$ of depth $d$ at which end it is reflected (so in total it travels ...
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2answers
265 views

What is deep Fresnel region?

If I understand correctly, it has something to do with autocorrelation function, but can someone give me a definition or exact explanation? In case of scattering, if you wish to analyze pattern with ...
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2answers
1k views

Why do mirages only appear on hot days?

A previous question asked why the road sometimes appears wet on hot days. The reason is that when there's a temperature gradient in the air, it causes a gradient in the index of refraction, causing ...
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1answer
1k views

How to turn water opaque by pouring the smallest quantity of matter into it? [closed]

Consider a glass of water and a glass of coffee. Their contents differ by no more than a few grams of particles coming from the roasted and ground coffee, yet the former lets almost all visible light ...
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3answers
313 views

mirror house gedanken experiment

Imagine a mirror house i.e. completely made of mirror with no traces of whatsoever light absorbent. Now, you introduce a light beam into that room and observe somehow through a hole. Would the room ...
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1answer
561 views

Compound lenses and virtual images

Ok so I have this problem where I have a system of two lenses. All I know is that the distance between the object and the first lens is 30cm, the distance between the object and the final image is ...
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2answers
203 views

What shape is formed by the set of all raindrops which create a rainbow to specific observer?

What shape is formed by the set of all raindrops which create a rainbow to specific observer? Maybe it's easier to narrow this down and consider it this in parts: what's the set of positions from ...
4
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1answer
255 views

what is the probability distribution for the angle of an approximate laserbeam

I'm trying to simulate the light distribution characteristics from a Gaussian laser beam, but having difficulty with the angular distribution. I need to generate a large number of points on an x/y ...
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1answer
1k views

Nonlinear polarization (second and third order)

Why does second order nonlinear polarization occur only in crystal materials with a non-centrosymmetric crystal structure? (Nonlinear effects at crystal surfaces are an exception). Why does third ...
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1answer
69 views

Linearizing Quantum Operators [duplicate]

Possible Duplicate: Linearizing Quantum Operators I was reading an article on harmonic generation and came across the following way of decomposing the photon field operator. $$ ...
3
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1answer
142 views

How does holographic voxel density scale with holographic film metrics?

I'm trying to understand how one can generate bounds on the effective number of voxels (volumetric pixels) in a hologram, or information density, provided various metrics for the two-dimensional ...
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787 views

How to use the Coddington shape factor?

We are given $\sigma=\frac{r2+r1}{r2-r1}$, with $\sigma$ being the Coddington shape factor. What I am having problems with is solving for $r1$ and $r2$ when I am just given a focal length and a ...
3
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2answers
490 views

why isn't the variance of Fano noise proportional to the number of photon arrivals?

I've been reading "Photon Transfer" by James Janesick and in Chapter 3 (http://spie.org/samples/PM170.pdf) he describes the various sources of noise in a CCD. Basically, incoming photons interact with ...
2
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1answer
512 views

Why does the speed of light within a solid depend on frequency?

Different frequencies of light travel at different speeds through solids, which along with Snell's law allows for rainbows. Has this phenomenon of variable speeds been predicted through derivations? ...
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0answers
80 views

Optics: finding total power of a syste, including wavelength

Specifically I need to create an ABCD matrix given 2 radii of curvatures, the thickness of the lens, type of glass (BK7) and a given wavelength. I will have to figure this out eventually, so help ...
2
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1answer
255 views

Extra help in Optics

I am in an optics class, and we are using the text "Introduction to Optics" third edition by Pedrotti. The book is completely useless in the course. The questions in the review section of the chapter ...
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4answers
357 views

How are we able to view an object in a room with bulb..?

This is a very basic question on optics. How are we able to view an object kept in a room with a bulb? From what I understand, light rays from bulb will hit the object and some colour will be ...
3
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1answer
578 views

How to set up a very simple experiment in optics?

This might come across as a very rudimentary question. My fundamentals of Optics are weak. In the optics chapter of my physics text book I saw diagrams each depicting an object on the left and a lens ...