Fabry–pérot Interferometer Puns

DBR has periodic layers of dielectric surfaces(say N1 and N2 are alternating layers), if one of its centre layer is defective (different in thickness) does it now behave like an Fabry–Pérot interferometer/resonator?

example structure [N1,N2,N1,N2,N1,N2,N1,N2,...N1(with deferent thickness ),N2,N1,N2,N1,N2,N1,N2,]

In other words can the cavity in FP resonator be replaced with the dielectric with different thickness?

We developed a photoanode consisting of Au-Ag alloy nanoparticles (NPs), a TiO 2 thin film and a Au film (AATA) under modal strong coupling conditions with a large splitting energy of 520 meV, which can be categorized into the "ultrastrong coupling regime". We fabricated a photoanode under ultrastrong coupling conditions to verify the relationship between the coupling strength and photoelectric conversion efficiency and successfully performed efficient photochemical reactions. The AATA photoanode showed 4.0% of the maximum incident photon-to-current efficiency (IPCE) obtained at 580 nm, and the internal quantum efficiency (IQE) was 4.1%.These results were attributed to the high hot-electron injection efficiency due to the larger near-field enhancement and relatively negative potential distribution of the hot electrons. Furthermore, hybrid mode-induced water oxidation using AATA structures was performed with a Faraday efficiency of more than 70% for O 2 evolution.

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This is hard for me to explain exactly, but i will try my best. I know Fabry-Perot interferometers can filter out wavelengths of light, but how accurate/specific is it?

1)For example can it separate only 1310nm wavelength from all of the other wavelengths ranging from UV, visible, and infrared?

2)Then is it possible to have another fabry-perot interferometer/etalon separate 1311 nm wavelength from that same group of wavelengths?

3)Is it possible for etalons to filter out decimal places in wavelengths of light? For example to separate 1310.5nm from 1310nm and 1311nm, and if so, what is the limit to how far the decimal place can go to be distinguished from other wavelengths of light.

4)Last question: why is it that most fiber-optic communication only uses the infrared spectrum of light and not ultra-violet through infrared all together. Correct me if I'm wrong, but wouldn't you be able to send more information using a ultraviolet with a higher frequency than infrared with a lower frequency?

edit: ty everyone for your answers, you really helped clear up my misconception.

Hi there,

I'm currently working on the electrical communications between a controller and Fabry-Perot Interferometer. Although it isn't completely necessary that I understand the physics of the sensor, I am curious.

Can anyone provide reference material regarding a Fabry-Perot interferometer as a displacement sensor? I've found material regarding the interferometer aspect, but not so much the application with regard to displacement.

Any help is appreciated!

I am trying to understand why fabry-perot interferometers give the interference bands they do. My question is: would the interference bands be the same if the photons of light were introduced one at a time, like in the two slit experiment? Basically I am asking if the fabry-perot interferometer is essentially an n-slit experiment, or if it works by some other principle.

Thanks

Good afternoon I should be doing more important work. Throwaway account because I'm mildly embarassed.

Short explanation:

Raw 23andme DNA said several pathogenic Fabry variants, I have heart disease already diagnosed so #yikes gotta check, already did some background research and it's clinically actionable when confirmed so I wanna do that bc I don't wanna die of heart disease in my thirties (as one does). How do I approach a doctor with this to get it confirmed or refuted, WHO do I approach with this, what tests do I do, I am lost and afraid lmao.

Long explanation:

So browsing raw DNA found three "pathogenic" GLA variants. "pathogenic" in quotations because of the likelihood that these are just incorrect calls, not because they're classified as ambiguous (they're considered straight up pathogenic when correct). I have RCV codes for them (somewhere around here).

The problem here is that I'm already diagnosed with heart disease which matches up to what people my age with fabry tend to have (tachyarrhythmia/AVNRT and valvular heart disease) so I don't really think I can ignore it or wave it off. The one SNP that I currently have pulled up is rs797044499, but there were multiple fun possibilities.

I know I def need a medical grade test to check bc consumer DNA is not diagnostic evidence but I don't know. Who I need to contact for this. I'm pretty sure if I go through official channels my insurance will cover (so say the coverage docs I read) but I still don't know how to FIND anyone.

EDIT: by medical grade test I still mean DNA since that's diagnostic standard for women. We don't show up abnormal on enzyme tests very well even with confirmed fabry.

Have any of y'all done this before?? it's confusing I hate finding doctors and I don't want my cardiologist to think I'm dumb

Does anyone have any suggestions for cheap interferometers or deflectometers for small flat surfaces?

I'm trying to give a recommendation for someone who wants to measure flats and prisms <10mm and fairly loose Irregularity/flattness requirements for its size.

What are your dirt cheap recommendations for interferometers? Any vendors known for budget interferometers, get something off ebay?

Also are there any commercially available deflectometers suited for precision optics measurements? I assume there might be some cheap options there. The QED deflectometer for mrf spot measurement comes to mind.

I need to take an elective to graduate this upcoming semester. I need the class that is easiest to pass. Preferably, no assignments. Just quizzes. And attendance not mandatory. BTW I have a science degree from Cegep.

Hi, im a 18 years old male from Chile. Fabry's disease has been in my family in generations. My grandma has it and her sisters too, some sons of her sisters have them too (two sons of one sister has them and another two also males from another sister). We as a family think is likely that my great grandfather was the one that had the disease since all his daughters have the disease and he also died in his 50s, unlike my great grandmother that died in his early 90s. So my question is, the children of my grandma (my mom and my two uncles one male and one female) tested themselves some years ago (I was 8) and they were negative, is it possible that they actually have the disease even if they appeared negative when they did it? And if my mom as example was lucky enough to not inherit the disease is it possible that me or my brother can have it?

I am experimenting with a laser diode (temperature and current stabilized) with an external cavity for wavelength-selective feedback (external cavity laser diode, ECDL). My goal is to make a nominally multi-mode laser diode (single transverse mode, multiple longitudinal modes) to operate in a single longitudinal mode to increase its coherence length for interferometric measurements.

In my interferometer setup, I divide the ECDL output into REF and OBJ arms by a 50:50 beamsplitter (BS). The REF beam is directed to camera sensor with a pair of mirrors and a second BS. The OBJ beam is phase-stepped by a piezoelectric actuator and aimed onto a diffuse object surface. A lens images a part of the scattered light onto the sensor, where it overlaps with the REF beam, producing an interference pattern.

The ECDL setup uses the classical Littrow configuration [https://www.rp-photonics.com/external_cavity_diode_lasers.html ]. With the help of an alignment disk, I have adjusted the external cavity (grating+mirror mounted onto same xy-tilt mirror) so that the diffracted beam enters back to the laser diode. I'm able to get the diode to lase slightly below the threshold by optimizing the grating angle.

The attached video shows the spectrum of the ECDL output, recorded using a makeshift spectrum analyzer. In the beginning, the grating is purposely de-tuned so that there is no feedback. I then tune the grating closer to Littrow angle. This leads to imperfect feedback that causes chaotic mode-hopping. When the feedback angle is optimized, the laser "locks" into a single mode (I believe). By tuning grating angle, a desired mode can be selected.

I have tuned the ECDL setup to the best of my abilities, and believe that it operates in single-longitudinal mode. However, the beam seems not to interfere properly, as the fringe contrast is low, and moving one of the interferometer arms by a piezo actuator causes barely any intensity modulation. This is puzzling, as the same laser diode interferes much more strongly when operated without any external feedback. Also, in the mode-hopping regime, the fringe contrast appears much higher, although the fringe pattern changes rapidly due to continuously varying set of lasing modes.

I have checked the beam polarizations at the sensor plane. They are within 10˚ from one another. I am now wondering whether any of the following issues could explain the poor interferome

If we built a 1km radio telescope on the far side of the moon, for example, could we link it up to the ones on earth well enough to create a massive interferometer? If it is possible what are the problems with it?

With the James Webb Space Telescope reaching its launch site in South America yesterday, I was wondering if it was possible to use it and the Hubble Space Telescope together as an interferometer? If it is possible, are there any plans to position them at opposite sides of Earth and use the telescopes as an interferometer?

Basically what im asking is if we had two telescopes at Earth L4 and L5 would they need to have such precise instruments that they are able to perfectly redirect the collected light to focus it at a point between them(or at one of the two telescopes). Or can they collected the data, transfer it electronically to Earth where it can be combined in a computer without the need for high precision instruments?

In two different textbooks, there are two different formulas with different derivation styles for the "No Fringe Formation" Condition.

In approach (a), they use an amalgamation of bright and dark for 2 wavelengths having very minute difference in the following manner:

2dcostheta=n*λ(1) -------- (1)

2dcostheta= (n+1/2)*λ(2) ----------- (2)

Subtracting both the equations we get, n=λ(2)/(2(∆λ))

Now using this value of 'n' for small angles in (1) we get d= λ(1)λ(2)/(4∆λ)

This is one formula.

In the other textbook they have said that fringe pattern may disappear for a bright of nth order and another bright for (n+1)th order. So proceeding in similar fashion as above (for small angles etc.)

2d=nλ(1)=n'λ(2) where n'=n+1

Thus n=λ(2)/{(λ(1)-λ(2)}

Using above value of n, we eventually get

d= λ(1)λ(2)/(2∆λ).

This is the other formula.

Now I would greatly appreciate if someone would help me understand which is the correct one because I used both of them and they apply for different questions which are of the type- "find separation of mirrors for which there is no fringe observed".

Both have a distinction of 1/2.

Hello everyone,

I was diagnosed with fabry disease in 2017, it runs on my mom’s side of the family. I currently do not have any symptoms, something that I’m thankful for. It seems like the women in my family dont present any symptoms until way later in life. However, recently I have become pregnant and know there’s a 50/50 chance my child will have fabry disease. I’ve been connected to a genetic counselor recently and he let my husband and I know he will talk to us about our options and how we can move forward. Now, I’m terrified I will have a son with Fabry disease considering the pain they suffer due to neuropathy starting at a young age. I know males definitely display symptoms and have pain at an early age. Many of my uncles have passed due to the this disease. I don’t know what the pain is like as I have not experienced it myself. I know prenatal testing can be done, but would it be wrong of me to have a child knowing he/she will have a disease that will leave them in pain? I know there’s enzyme replacement therapy but I know that won’t help the neuropathic pain they experience. I’m so torn.