Questions tagged [diffraction]
Diffraction is defined as the bending or flaring of light around the corners of an obstacle or aperture into the region of geometrical shadow of the obstacle. This flaring is consistent with the spreading of wavelets in the Huygens construction. Diffraction occurs for waves of all types, not just light.
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Angular width of a diffraction grating maximum [closed]
So there is a diffraction grating where there are N slits, all with a distance d between one another. The light passing through the slits is coherent.
We are concerned with finding the angular width ...
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When is the 3D Dirac delta function a good approximation for scattering?
When discussing X-ray or neutron scattering, it is usually assumed that the scattering potential is of the form
$$V_{\mathrm{eff}}(\mathbf{r}) = \sum_i b_i \delta^3(\mathbf{r}-\mathbf{r}_i)$$
with $...
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X-ray diffraction "linewidth" due to thermal motion
I was recently learning about X-ray diffraction and I am a bit confused about how thermal motion affects the measurement.
If I understand it correctly, when measuring crystals, thermal motion does not ...
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Diffraction Modeling Question
I'm trying to implement a model for diffraction-limited imaging, following "Microlithography" by Sheats and Smith. You can skip to the bottom for my question, but I'll explain the setup ...
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Why in the derivation of Bragg's law, the incident angle = scattered angle? [duplicate]
In the derivation of Bragg's law in Wikipedia here, they assumed that the incident angle is equal to the scattered angle. But every layer of atoms should act like a diffraction grating. Is somehow in ...
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What is the difference between diffraction and scattering?
In the context of acoustic waves interacting with small particles (for example, in medical ultrasound imaging of biological samples) I often read that when a wave encounters a particle whose size is ...
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Diffraction through thick media
I want to calculate the diffraction pattern of light using (e.g.) the Rayleigh-Sommerfeld diffraction model.
For this, I am using the Python library Torchoptics.
However, I am struggeling on how to ...
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Various Expressions for Fresnel distance [duplicate]
I've come across multiple formulas for the Fresnel distance in optics, which describes the transition point between the near-field (Fresnel diffraction) and far-field (Fraunhofer diffraction) regions. ...
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Reference request: How to calculate a straight edge diffraction pattern?
The Physics Stack article of 01/28/2016 on Calculating a Straight Edge Diffraction Pattern does not provide a scientific journal or textbook citation for the equation used. If there is one, what is it?...
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What is the practical difference between Fresnel diffraction and Fraunhofer diffraction? [duplicate]
Recently, I am studying about waves. I studied about Fresnel and Fraunhofer diffraction. I understand that the difference between Fresnel and Fraunhofer diffraction is that, in the first case, the ...
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In Young's Double Slit Experiment, what happens if one of the slits is being covered gradually?
I am really confused about the result that we will receive when one of the slits in YDSE is gradually being covered.
My assumption is that since the phase difference is the same, the positions of ...
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Should convolution between point spread function & geometrical prediction of image be carried out before or after magnifying one of the two functions?
In "Introduction to Fourier optics" by Goodman, on page 114 it states that for a diffraction limited imaging system:
The ideal image produced by a diffraction-limited optical system (i.e. a ...
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About spatial energy distribution of light emitted by a laser pointer
This question is triggered by a section in the Veritasium video "Infinite Slit Paradox: Something Strange Happens When You Trust QM" about Feynman's path integral that came out on March 5, ...
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What is the explanation for different diffraction patterns 1cm behind grid vs. on distant screen?
I have a question regarding the following experiment.
I wanted to see what a laser beam diffraction behind a grid looks like up close. I chose the following set up:
That is, the grid is a combination ...
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Derivaton of the smallest spot for a monochromatic beam (Helmholtz equation solution)
Although this is not necessarily a question anymore since I have the answer, I'm still posting it since it took me way to long to get to the answer and maybe others would find it useful. By taking way ...
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Why do we see multiple Bragg peaks?
I am not sure how to connect the Bragg-law to experiment.
Suppose i let a wavelenght $\lambda$ fall incident to a surface of a metal at angle $\theta$. The wavelenght and the angle are unchanged. then ...
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Will the results from two diffraction experiment under exactly the same conditions be completely identical?
If two electron diffraction experiments are conducted under exactly the same conditions and are randomly stopped at the same time, will the results be completely identical? That is, will the ...
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Shouldn't the fringe width be the diff bw a dark and bright fringe instaed of distance bw consecutive bright or dark fringes?
Distance to 10th maxima =10lambda D/d
Distance to 10th minima 10.5 lambda D/d
So should the fringe width be 0.5 since 10th minima is 0.5 above 10th maxima so shouldn't it be rhe fringe wid th, if not ...
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Why does an infinitesimal slit act as an isotropic light source
For a finite slit, the expression for irradiance is as follows,
$$I=I_0\operatorname{sinc}^2\beta$$
where
\begin{array}{ccc}I_0=\frac{1}{2}\left(\frac{bE_r}{r_0}\right)^2&\text{and}&\beta=\...
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The diffraction of the Gaussian beam on a curved mirror?
I am studying diffraction. While going through multiple examples, I have understood the diffraction of plane waves passing through a finite size lens. However, it is not easy to qualitatively think ...
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Why do electrons not pass through a screen?
Rutherford aimed alpha particles (helium nuclei) at a gold foil and found that most of them went right through and only a few bounced back. If we aim deuterium nuclei (deuterons) at a gold foil we ...
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Single Slit Diffraction Using White Light
So some days before i prepared a single slit using razor blade and taken mobile flashlight as white light source and tried to do single slit diffraction with white light but what happens that i do ...
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Will we get any diffraction pattern in this case?
We get to see diffraction patterns when light from a coherent source passes through a thin slit. But consider a mirror with a line scratch on it (as shown in the figure) and we shine a red light from ...
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A diffraction pattern without central maxima?
In some smartphone charger there exists a bulb (LED) most probably which emits light when charger is plugged in. I have noticed that light coming from that bulb causing diffraction pattern on the wall....
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Why must slit be of order $\lambda$ for radial diffraction?
I've read quite a few posts asking a similar question but I suppose I'm still not quite satisfied with the explanations (hence the question).
I'm aware that diffraction always occurs and I know the ...
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