Tagged Questions

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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Finding out the minimum deviation angle [duplicate]

Let a light incident on a prisom at right angle. I want to determine the minimum deviation angle. I know a relation $$\frac{\cos i_1}{\cos r_1} = \frac{\sin i_1}{\sin r_1}$$ and minimum angle of ...
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Holographic Image

In a holography set-up, as shown in the figure below, Illumination beam and reference beam both are in phase. The interference pattern generated at the detector contains the whole information about ...
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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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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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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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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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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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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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Polarization of light

So for my experimental optics class, I had to create a device that would emit horizontally polarized light such that its intensity is independent of an incoming linearly polarized beam of arbitrary ...
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Semiclassical description of EM waves reflection from metallic surfaces

Imagine an EM wave impinging on a metal. Fresnel's formulas tell us that no wave can propagate through the metal, or that the transmitted field is an evascent wave with some penetration depth ...
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Paralel light conditions after passing from a sphere

Is it possible to get such result that light will be parallel after passing from the sphere? what is the total condition for such result if possible? Thanks for answers
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Intensifying a light source using black body concept

Is it possible to intensify light by initially passing it through an apparatus like a perfectly black body and then through a colloidal solution? What kind of material can be used inside the ...
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Full refraction in fibre optics

Well in a problem I had to calculate the maximum amount of "reflections" in a glass fibre optic pipe (index of refraction = 1.3, width of 20 micrometer and length of 1 meter). I am a bit blocked on ...
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Magnifying factors of multiple lenses (closely packed)

Well the following question I really struggle to find an answer A thin lens creates an image of an object with magnification -3. A second identical lens is positioned very close to the first ...
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Is there any optical phenomenon can't be explained without magnetic field?

Almost all optical phenomenon can be explained considering a fluctuating electric field. Is there any optical phenomenon which can't be explained without considering two fluctuating fields, electric ...
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Vibrations after polarization of light

When we polarize a light, do we get electric vibrations, magnetic vibrations or the mixture of both. If both, then how can both electric and magnetic vibrations occur in single plane because ...
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Understanding a paper: What is the meaning of $b_0$?

I am looking at this paper (Multicoated gratings, J. Opt. Soc. Am., 1981) and I am getting confused around equation 22. I do not completely understand where he comes up with the equation \xi^j_q=...
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Calculating the magnification of an optical microscopy system

I have a microscopy system that is set up as follows : DSLR with a crop factor of 1.6x ( equivalent to magnification, I believe ) An adaptor optic, for attach the DSLR to the microscope, listed as a ...
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Effect of slits and a lens

We have a screen with two slits (Young style) separated by a distance $d$, one of them receives a planar wave of $600nm$, the other receives a planar wave of $400nm$. Behind the slits there's a screen ...
615 views

Simple Question: Speed of Electromagnetic Waves in a Medium

If the speed of an electromagnetic wave in a particular medium is such that $v = c$, the speed of light, does this mean that the permeability $\mu = \mu_0$, i.e. that of a vacuum and the index of ...
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Reflection of a polarised beam

The past days I've been trying to understand how AutoFocus(AF) works on photographic cameras. There is a statement that says AF systems are polarisation sensitive. This means that they can only work ...
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State emitting from an extended thermal source

This calculation is for a double slit experiment setup which is experiencing a far field radiation from an extended monochromatic thermal source. I assume the source is 1-D and it's length is $b$. ...
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Apparent and real depth object in water [closed]

Did I get my formula right? Seems like the correct answer is $d_o = 1.33 \times d_i$ but I thought the formula I should use is $d_i = - \frac{n_2}{n_1} d_o$
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Keep the light beam in a closed room, is it possible? [duplicate]

I mean if I am in a room totally closed to light. If I switch on a torch for a second then switch it off. So will the inside of room be always bright?
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Is a holographic recorder able to capture a large full color picture? [closed]

Is it practical to attempt to build a 3D hologram generator that is full color and big enough to recreate a watermelon full size? If so, is real-time control feasible?
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Trapping EM radiation [duplicate]

Is there a material which can allow light (or any other EM radiation) to pass through from one side as if it is transparent but its other side reflects light like a mirror?
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How to calculate the height and length of a reflected ray?

I barely know anything about optics, so I could use some help about how to go about solving this problem. If I have a ray of light at a certain height from the optical axis, propagating at an angle, ...
533 views

Beam waist at extremely long distances

A beam of light of wavelength $\lambda$ and width $W$ needs to be focused at a distance $D$ to a spot not bigger than $w_S$, which stands for 'width of sail'. Now, the diffraction limit says it ...
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How reflected objects are composed and who is responsible for that?

Please refer to this image. The scene contains an object close to a mirror in the wall and a window, note that the reflected object is receiving more light than the object itself. I read some ...
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Kiessig fringes

I have come across many papers but still couldn't find the relationship between index of refraction or atomic scattering factors, and reflectivity. My flow of thought goes as follows: Get the ...
492 views

How big of a lens or parabolic mirror would it take

...to heat a piece of steel so its glowing yellow (1100 C)? Assuming you had a cloudless day at a latitude of, say, San Francisco... Basically I'm wondering if it is possible/feasible to be able to ...
86 views

Rays in Symmetric Resonator

I'm having some trouble figuring out how to get started on this question: If I have a symmetric resonator with two concave mirrors of radii $R$ separated by a certain distance, after how many round ...
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E and H fields created by fiber optics?

When an EM wave travels down a conductor, it creates and electric and magnetic field around (H) the wire and normal to (E) the wire. My question is, when light travels down an optical material such ...
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Why does heterodyne laser Doppler vibrometry require a modulating frequency shift?

On the wikipedia article (and other texts such as Optical Inspections of Microsystems) for laser Doppler vibrometry, it states that a modulating frequency must be added such that the detector can ...
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Does a FTS work on the same principle as a michelson (amplitude division) interferometer?

As far as I can tell within an Fourier Transform Spectrometer the spectral information is gained from changing the path length along one arm, this sounds very similar to a michelson interferometer but ...
192 views

Physics of Fireworks

This evening I saw the 4th July classic Fireworks in San Diego, and I was wondering about the most physical picture of what was happening. Does anyone have a good way to explain the detailed physical ...
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Find the dispersion of the slab?

I've been having trouble with this for a few days and already used up all my tries on the homework for it, but have the final is coming next week. Thus I would like to know how do this, however I ...
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size and distance of mirror used in projected “smart” whiteboard

Apologies in advance for complete ignorance of optics (beyond conic sections) How is the size, distance, and angle of the mirror used here calculated? The mirror is I believe the open flap in front ...
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Intensity distribution of a LED light source

The light source: 190 high power LEDs in NIR. I have the datasheet of the LED. I want to make a graph showing the spatial distribution, and to measure the intensity of the beam on the whole field of ...
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Can a complex lens be represented by wavefront aberrations?

Usually complex lenses are described by their geometric design - usually a sequence of spherical cap sufraces and materials. The lens behavior, ie. how it transfers rays, can be evaluated by ray ...
244 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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The further the focal length, would more or less be projected in the image?

When the focal length of a camera gets further, the object projected on the image gets larger. But would more or less of the object be projected on the image? I know the answer is that less of the ...
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Creating the opposite of an optical lattice

Is it possible to create periodic potentials that instead of creating a well for an atom to be trapped in, repulsed by that specific location? If yes, can we use this as a means to make artificial ...
190 views

What software can I use to simulate supersonic gas particle flow? [closed]

Please please help me out with this. I am trying to find a software/program that I could use the simulate the scattering effect of light when it strikes gas particles moving at supersonic speeds? ...
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Alkali metal transparent to UV - is cesium (somewhat) transparent to visible blue light?

Most optics texts will mention that alkali metals can become transparent in the near ultraviolet in the sections on reflections from metals, plasma frequency, and electron density. I remembered this ...
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Spherical aberration: circle of least confusion and diffraction limited spot size

I need an estimate of the relative sizes of the circle of least confusion (spherical aberration) and the diffraction limited spot size for typical real lenses. I've seen plenty of discussions, but ...
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Why is the angle of incidence shift in band rejection filter spectra minimized by high refractive index materials?

I would like to know why the angle of incidence shift in band rejection filter spectra and separation of S and P polarized light is minimized by high refractive index materials. The reason I ask this ...
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Simulating a noisy image: Poisson Noise Clarification

I'm currently working to simulate an image that mirrors the output of a CMOS camera we have in the lab. My images include Poisson (photon) noise as well as a gaussian (readout) noise. My issue is ...