All Questions
15
questions
1
vote
0
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51
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What is the connection between Ray (Geometric) optics and Electromagnetic theory optics in fiber optics?
I am currently reading about fiber optics and wave propagation in fiber optics and encountered the following part of Gerd Keiser's Book :
according to the diagram shown, its a general case when the ...
4
votes
3
answers
244
views
Can a fibre preserve the shape of the light being transported through it?
Can some fibres retain the shape of the light being transported through them?
If I emit radiation towards a sample (in the shape of an "S") and this is reflected back into a fibre, will the ...
- 753
1
vote
3
answers
262
views
Zero-dispersion wavelength
Please help me understanding the zero-dispersion wavelength in fibers.
I found this wiki-article on the topic. Accordingly:
"In a single-mode optical fiber, the zero-dispersion wavelength is the ...
- 113
1
vote
0
answers
30
views
Existence of $\mathrm{HE}_{11}$ mode in optical fibers for $v \to 0$
In a step-index optical fiber, the eigenvalue equation for the $\mathrm{HE}_{11}$ fundamental mode, under the weak guidance approximation, can be written as
$$\frac{J'_n (u)}{u J_n (u)} = - \frac{K'_n ...
- 767
1
vote
1
answer
275
views
Effective refractive index can be equal zero?
Can someone please explain the cases that the Effective refractive index $n$ on it can be equal zero? Does such a situation even exist?
I am trying to solve an ordinary differential equation to find ...
- 11
0
votes
1
answer
631
views
Confinement factor for an optical fiber
I was reading the chapter about optical fibers of "Fiber - optic communication systems" and I have read this statement:
The fraction of the power contained in the core is given by the
...
- 1,319
0
votes
1
answer
85
views
Gradient Force of optical near field
Source: Principles of Nano-Optics, for Lukas Novotny and Bert Hecht.
The equations above represent the electric field in the second medium when a light hit a surface and the condition of TIR (total ...
- 39
1
vote
2
answers
613
views
Plot the eigenvalue equation for optical fibers LP modes
The eigenvalue equation for LP modes in Optical Fibers is:
$$\frac{J_{\ell - 1}(u)}{J_{\ell}(u)} = -\frac{w}{u} \frac{K_{\ell - 1}(w)}{K_{\ell}(w)}$$
where:
$J_{\ell}(u)$ is the Bessel function of ...
- 767
0
votes
2
answers
62
views
Optical fibers eigenvalue equation considering $\phi$ dependency
Consider the system of equations formulated in a previous question (optical fibers continuity of tangent field components across the core-cladding interface):
$$
\left\{
\begin{array}{c}
e_z^{(1)}(r,\...
- 767
0
votes
1
answer
117
views
Optical fibers field analysis, $\phi$ dependence not considered
In optical fibers, the core (with $\varepsilon = \varepsilon_1$) is usually represented by a cylinder of radius $a$, whose axis coincides with the $z$-axis in cylindrical coordinates. The cladding is ...
- 767
0
votes
1
answer
246
views
Is the length of a distributed Bragg reflector $= λ / 4$ so that one mirror is at a maximum?
Am I correct in my assumption that the ideal length for a distributed Bragg reflector (DBR) is the wavelength of light over 4, so that one of the mirrors is at a maximum for each photon... and this ...
- 127
2
votes
2
answers
964
views
Self-phase modulation induced spectral broadening
How does one explain the fact that a pulse that has its phase modulated through SPM, generates new frequencies? How does the phase modulation affect the electrons so they emit not only the frequencies ...
- 474
2
votes
1
answer
3k
views
How to calculate loss due to Gaussian beam divergence of a laser going through multiple lenses?
To better explain my question, I will need to give a brief description of the configuration used in 2D MEMS switches.
So, the next figure shows a configuration of a 2D MEMS switch, a light beam ...
- 45
2
votes
1
answer
381
views
Characteristic quantities in Fiber optics
I'm having trouble finding typical quantities in fiber optic communication. In particular, what kind of powers are generally used (or what is the minimum that fiber optics receivers can detect ...
- 14.2k
5
votes
5
answers
10k
views
Efficiencies of Coupling Light into a Fiber
I am in AMO Physics and work a lot with optics. I just wanted to get an idea of what coupling efficiencies one "should" get in a "reasonable time"* by coupling light into a fiber using different ...
- 373