All Questions
13
questions
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96
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How to compute the diffraction efficiency of a thin phase grating with arbitrary groove shape?
From Magnusson and Gaylord (1978), the wave amplitudes, $S_i(z)$, of $p$-polarized light for a thin, arbitrary phase grating are given by the equation
$$
\frac{\partial S_i}{\partial z} + \gamma \sum_{...
- 123
1
vote
2
answers
189
views
Diffraction limit PSF and angular spectrum method?
I know from the angular spectrum method that given a field $U$ with a wavelength $\lambda$, we can decompose it with Fourier transform.
\begin{equation}
U(x, y,0) = \int \int {\tilde{U}_0(f_x,f_y)} ...
- 444
1
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0
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33
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Are plane waves always transverse in Fourier Optics?
In Fourier optics one decomposes the field into plane waves to find the solution of the scalar Helmholz equation. The scalar means that the electric field $\vec{E}$ is aligned towards only one ...
- 171
1
vote
1
answer
110
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Electromagnetic radiation of dipole in the frequency domain
Recently I've met a formaula that says the radiation power of a dipole in the frequency domain is $I(\omega) = |\omega^2P(\omega)|^2$, where $\omega$ is the frequency of the radiation and $P(\omega)$ ...
- 111
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votes
3
answers
845
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What Plane Waves Make a Gaussian Beam?
When I think of a light beam, what first comes to mind is this:
Black lines are axes (both spatial axes, at a snapshot in time), and blue lines represent the surfaces of constant phase of a plane ...
- 1,544
1
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1
answer
32
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How to properly calibrate phase axis to represent an optical interferometric stability curve?
Assume we want to measure how stable an interferometer is.
We send two ultrashort pulses (left figure), delayed by the fixed time $\Delta t=T$ relative to each other, into a spectrometer to observe ...
- 1,030
1
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2
answers
374
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Is Fourier analysis applicable to lightwaves?
I'm a mathematician with little understanding of physics.
My questions: In mathematics, we decompose a wave into its elementary parts by using the Fourier transform.
Is this process applicable to ...
3
votes
2
answers
293
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Impossibility of Monochromatic Light [duplicate]
Pages 24-25 of my textbook, Optics by Hecht, says the following:
Using the above definitions we can write a number of equivalent expressions for the traveling harmonic wave:
$$\psi = A\sin k(x \...
- 889
1
vote
1
answer
943
views
Rayleigh-Sommerfeld Formula: Explanation of these terms?
Can somebody explain the physical meaning of the last exponential term, $e^{j2\pi f_xx+j\pi f_yy}$, in the Rayleigh-Sommerfeld Formula?
Please correct me if I'm wrong, but I understand that $\...
- 1,325
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votes
2
answers
319
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Why is this question indicating a Fraunhofer Region rather than Fresnel Region?
I was thinking that because the source plane is infinitely large would be analogous to having the source plane being infinitely close, which would imply a Fresnel region rather than Fraunhofer.
...
- 1,325
2
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0
answers
252
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Simulation of beam propagation with mirrors and lenses
I like to simulate the propagation of the wave front of an arbitrary 2d electric field. The free space propagation can be modeled in the paraxial approximation via the Fresnel equation using Fourier ...
- 358
3
votes
2
answers
2k
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Difference between the paraxial approximation and the Fresnel approximation
I'm currently reading literature about diffraction (especially Rayleigh/Sommerfeld-Diffraction, or the equivalent fourier-method), and I'm stumbling across the terms "paraxial approximation" and "...
- 6,763
1
vote
1
answer
381
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Propagating higher order Hermite Gaussian modes. What are complex amplitude coefficients?
I've been tasked with writing a code (in MatLab, but I'm currently using Mathematica because I don't know MatLab %\ ...) to simulate the propagation of a Gaussian beam.
I don't really know anything ...
- 193