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]
1127 questions
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Trying to combine red, green and blue to produce white
I tried to mimic the mechanism of typical screens to produce white color out of red, green and blue.
What I did is displayed the attached image on the screen, and moved far away as to let the diffraction effects take place, so that the three colors…
kalkanistovinko
- 1,407
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3 answers
Fraunhofer diffraction contradiction
Assume two obstacles are complementary. For example, a circular aperture and a circular stop of same radii. My theoretical analysis leads to contradictory conclusions about such situations.
1) Assuming incident light is a plane wave consisting of N…
Teacher77
- 347
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Diffraction by small holes
This is a follow-up to this question: What happens to waves when they hit smaller apertures than their wavelenghts?
Hans Bethe wrote a paper in 1944, "Theory of Diffraction by Small Holes," Phys. Rev. 66, 163. I don't have access to the paper, but…
user4552
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3 answers
is this the difraction limit of our microscope?
I took the picture below with our microscope.
It's a 8mm roller bearing, lighted from below with a parallel light bundel (white).
The width of the yellowish light fringe is maybe 5 micron.
Originally I was hoping to make pictures with an accuracy of…
MTH
- 75
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3 answers
Diffraction in Electromagnetic Waves
Diffraction can be observed in physical waves very easily, however when it comes to the diffraction of electromagnetic waves in things like the single slit experiment, I become a little confused. In things like water, it seems like there is…
user24082
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2 answers
What is Diffraction?
Diffraction is just light interacting with small objects, and bending, but this seems like a very imprecise definition to me. What is diffraction, actually? I was confused because there are at least two diffraction gratings, that I know of. One…
user24082
4
votes
1 answer
Differences between single-slit/obstacle diffraction
In class, we have derived the formula for a single slit diffraction (slit length $a$) and it seems that the same equations are used when talking about diffraction around an obstacle of width $a$ (like a human hair). Why's that?
Dory
- 75
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2 answers
Pinhole diffraction conundrum
I've been playing around with laser diffraction quite a bit lately.
Yesterday I tried to have a shot at diffraction of a laser beam with a pinhole.
The pinhole was created by slowly penetrating a piece of heavy duty kitchen tin foil ($\text{Al}$),…
Gert
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1 answer
How small can diffraction grating be?
Like in title, how small can diffraction grating be? And, of course be "fully operational".
I mean, littles diffraction grating possible that still works as full-sized one.
Dreat
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3
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2 answers
Secondary maximum in Fraunhofer/single-slit diffraction
Question:
The angular position at which first minima is observed is $\theta=\pi/6$ rad for a slit of width $e$ and light of wavelength $\lambda$. The angular position at which secondary maximum is observed is = ?
My attempt:
For first minima,…
Gaurang Tandon
- 821
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1 answer
Abbe diffraction limit and Fourier
I am trying to understand the diffraction limited spot calculation. If my understanding is correct, the calculation uses the idea of Huygens wavelet where there are multiple point emitters on the lens. Summing the contributions from these spot we…
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Airy Pattern as infinite sum of Fraunhoffer Patterns
Is there a way to view the Airy Pattern as an infinite sum of Fraunhoffer diffraction patterns? I don't know where the 1.22 would come from then. Is there something inherently wrong with collapsing diffraction slits to infinitely small slits?
user24082
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1 answer
Why is the central maximum of single slit diffraction pattern wider than other fringes?
I had answered a question Single Slit Diffraction Experiment, telling why the central maximum is the brightest one, but it asks:
Why is the central maximum twice as wide as the others?
Now, that is tricking me, I have tried my best to search the…
PranshuKhandal
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2
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1 answer
Diffraction grating produces two central maxima
I was performing a diffraction grating experiment using a grating spectrometer (shown in the picture) and noticed that at zeroth order there were two closely spaced images of the slit. The grating was placed perpendicularly to the collimator and…
user2921731
- 41
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1 answer
single slit diffraction - $\sin\theta=n(\lambda)/b $ or $\sin\theta = (2n+1)(\lambda)/b$
I'm getting a contradiction as follows and am not sure how to resolve it:
logic 1
leads to the conclusion that the higher order minimas of single slit diffraction will be given by $b\sin\theta = n(\lambda)$ where $n = 1,2,3,\dots$ (this is given in…
Gyaneshwaran
- 21