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.
Questions tagged [diffraction]
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Can the Huygens principle be justified rigorously mathematically?
Can the Huygens principle be justified rigorously mathematically? To what extent and what purpose is it still relevant today? Is it made obsolete by the Maxwell equations? If not, do the Maxwell equations justify it?
pie
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Why can I see my fingers connected when they haven't touched?
If you take a close look at one of your fingers with one eye, it’s like your finger has an atmosphere with several layers(!): Now get two of your fingers so close that their atmospheres touch, you see a bridge connecting them that gets wider the…
S.Shahsiah
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What is the basis of Huygens principle?
When we were studying mechanical waves like sound waves, and waves on strings in class, we never studied Huygens' principle with these - and nor did we really derive the laws of reflection or refraction with them. We always in any case took them to…
Charles
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Does light reach geometrically inaccessible cavities without path measurement (analogy to the double-slit experiment)?
I have a conceptual question that mixes geometrical optics and quantum behavior of light, and I would like to understand whether my reasoning is valid. Consider a structure similar to a “Penrose room”: a nearly oval cavity with multiple small side…
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Is Kirchhoff's scalar theory of diffraction mathematically inconsistent?
I've heard that Kirchhoff's scalar diffraction theory is mathematically inconsistent. Is this true? If so, where in the formulation does this inconsistency arise and are there ways to remedy it?
Aiden
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Unexpected laser pattern through calcite crystal
I've bought a calcite crystal and tried to see birefringence by shining a laser through it. I get a split spot in the centre of a sixfold pattern The hexagonal pattern resembles a diffraction pattern, but I can't figure out what should cause it. The…
mrf1g12
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Fourier transform of almost-periodic lattice?
For a perfectly periodic lattice of atoms, the density can be written as a Fourier series like any other periodic function. This Fourier representation is very useful, because it can be connected to peaks you can measure with diffraction.…
KF Gauss
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Wavelength used in manufacturing of integrated circuits (IC)
How is it that the silicon ICs industry can burn ICs of a dozen nanometers using photolytography with UV laser of about 193 nanometers? Since the gates are smaller than the wavelength, for example 22 nm , the mask would filter/diffract the light,…
Damien Fléty
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Fresnel distance and Geometrical limit
I read about the geometrical limit of wave theory. The source from where I read had a slightly different explanation to provide than here (The more rigorous answer is too complicated for me to understand). Though I do not understand completely the…
stochastic13
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How can a single slit diffraction produce an interference pattern?
How can a light passed though a single slit produce a similar interference pattern to the double-slit experiment? How does the diffracted wave produce the points of cancellation and reinforcement, if there is only one wave?
Saras
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How do we know that bending of light around stars is due to bending of space-time and not diffraction?
One question that popped up during the studies of special and general relativity (which I am forced to take unfortunately) is the following: How do we know that this is due to the bending of space-time and not just plain old 3rd semester…
Dominik Car
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How did Arago find the Arago Spot without a laser?
Famously, Poisson showed that Fresnel's wave model of light would predict a bright spot in the very center of a circular shadow, which he interpreted as an absurd result. But Arago was able to perform the experiment, giving strong evidence toward…
i_am_goose
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Diffraction by a lens
The fraunhoffer treatment of circular apertures yields a diffraction pattern of circles, with the first minimum (dark ring) at an angular radius of $\theta$ where $\sin(\theta)=1.22\lambda/b$, where $b$ is the diameter of the circular aperture. But…
stochastic13
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Microscope Resolution vs Telescope Resolution
When referring to diffraction limit resolution of optical systems, one apparently gets different answers whether the system is a telescope or a microscope. Assume in both cases a lens (or mirror) with aperture $D$ , focal length $f$ and distance $R$…
TomY
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Will a football (soccer) diffract?
Apparently all objects have wavelike properties, so, if we kick a football (soccer ball, if you must) through a pair of posts, does the ball in any sense diffract? If this is ridiculous then let me know and I will delete the question.
user27182
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