2,698 reputation
1225
bio website nl.linkedin.com/in/…
location Canada
age 33
visits member for 4 years, 6 months
seen 18 hours ago

Apr
24
comment Is there any review paper on spatial light modulator?
I don't know of a review paper, but I have a technical report from quite a while back, about characterizing a micro mirror array, which is a specific type of spatial light modulator.
Mar
8
comment Resonant vs. Non-resonant Raman
I have never known for sure, but I suspect it is because the molecule is more likely to absorb and re-emit photons at those frequencies on the whole.
Jan
22
comment How to measure the size of a laser dot?
If you can pry the lens off the front of the camera, there is an easier way to get the size of the pixels on the sensor: illuminate the sensor directly with the beam, place a screen at a known distance from the sensor, and measure the distance (and therefore the angle) between the spots in the back-reflected diffraction pattern.
Nov
13
comment Do TN and IPS displays are subject to diffraction?
Don't overestimate others' familiarity with what seems easy to you. I learned what TN means long after I learned what a display is, and I have no idea what IPS is.
Oct
11
comment Collinearity of two infrared (10.6um) beams
While you're on the subject of safety, I'd suggest having the combined beam travelling horizontally, not upwards!
Sep
16
comment Transfer matrices - drift distances
I was thinking that would only work if $d$ was large compared with the difference in thickness due to the curvature of the lens; otherwise $d$ would not be constant in the distance from the optical axis, and so the transfer matrix would not work.
Aug
25
comment Why is optical orbital angular momentum (OAM) called “topological charge”?
Something else to point out is that the topological charge can be positive and negative and also adds up like electrical charge.
Jul
12
comment Anomalous Total Transmittance
You can't get out more energy than you put in, so I would guess something's wrong with your calibration.
Jun
15
comment Third-order susceptibilities of metals?
Cu nanocrystals embedded in glass, though, wouldn't be able to tell much about the solid metal, right?
Mar
13
comment Getting nonphysical results when solving for the index of refraction of a slab?
I was giving you long conjectures in the comments and finally I decided to stop conjecturing and make a real answer out of it ;-)
Mar
12
comment Getting nonphysical results when solving for the index of refraction of a slab?
What @SteveB says: It would not be at all surprising for this kind of data to be systematically shifted up or down a bit compared to reality. This has happened to me many times.
Mar
11
comment Getting nonphysical results when solving for the index of refraction of a slab?
How did you normalize your R and T measurements? Out of curiosity, what happens with the computed n if you add an offset of 0.2 to either?
Mar
5
comment Optics - Faraday Rotator using waveplates
You can't. Waveplates are reversible, a Faraday rotator is not.
Dec
13
comment Why is the decibel scale logarithmic?
That's incorrect, the decibel scale is logarithmic: +10 dB gives 10x the sound pressure (and +3 dB gives about 2x, as you say) so +20 dB (100-80) gives 100x. In other words, $2^{(100-80)/3} \approx 100$.
Dec
12
comment Exciting Surface Plasmon-Polaritons with Grating Coupling
Take $\theta_o = \pi/2$, so the grating equation becomes $d(\sin\theta+1)=\nu\lambda$. Then $k=2\pi/\lambda$, and $g=2\pi/d$. The difference between $k$ and $\beta$ is because $\lambda$ is different for the surface plasmon.
Sep
28
comment Law of reversibility of light and total internal reflection
Time-reversal symmetry still holds over a boundary between media (though not if the media are lossy.) In the general case you would get four beams, yes, but if you reverse the reflected and transmitted beams and they come together again with the appropriate relative phase difference that they had in the forward case, then they will destructively interfere in the pathway of the fourth beam, and all the energy ends up in the original beam.
Aug
1
comment Vibrations after polarization of light
They don't oscillate in a single plane. The electric field oscillates in a plane, and the magnetic field oscillates in a plane perpendicular to the electric field. The plane of polarized light refers to the plane in which the electric field oscillates, not the magnetic field.
Jul
27
comment Vibrations after polarization of light
In a plane wave, the electric and magnetic fields always both oscillate, and they always both oscillate perpendicular to each other.
Jul
13
comment Transmission vs reflection grating
I think no-one's answered this yet because it really depends on what you're trying to do with it. Can you make your question more specific?
May
12
comment What's the physical significance of using fourier transform for diffraction?
I wrote an answer about that here a while ago...