Science topics: PhysicsOpticsFiber OpticsOptical Fibers
Optical Fibers - Science topic
Thin strands of transparent material, usually glass, that are used for transmitting light waves over long distances.
Questions related to Optical Fibers
We working on translucent concrete. Could anyone help us giving the vendor/supplier details for using in translucent concrete? Thanks in advance.
I wanted to know if a lensed fiber can guide a light of wavelength (1550 nm) longer than the working wavelength of the fiber (780 nm).
I want to optimize the different parameters to limit the dispersion in the optical fiber, which objective function to use according to these parameters, and the initial dispersion in order to estimate the error, thank you in advance
Almost all optical fiber manufacturers produce optical fiber bobbins length of maximum 50 to 100kms. If longer length bobbins are produced then it will be easy for both user and producer as it reduces cost.
suggest If any technical papers available on this
I asked about nonlinear phase shift φNL in optical fiber. How can estimation φNL? and how the power effected on it?
I am trying to modify optical fiber with gold nanoparticles for particle plasmon resonance applications.
I am using 2% 3-Mercaptopropyl)dimethoxysilane (MPDMS)/Toluene as silanization.
I tried different time of fiber immersion in MPDMS (2 to 20h) and gold nanoparticle solution(2-16h). But no gold particles(AuNPs) stick to the optical fiber.
Can anyone give me some suggestions how to do this?
You can also suggest some other easy ways to modify fiber with AuNPs.
I am currently working on optical fiber. It would be great if I get some suggestion on books or tutorials to study in details of optical fiber starting from the basic theories.
How can we draw a graph of transmission in terms of wavelength in optical fiber sensors? Is there a mathematical formula in this field?
I want to proceed the experiment using optical fiber. However, there is a problem. In one of the processes, the temperature reaches almost 600 degrees(Celsius). I know that the glass transition temperature of the soda lime glass is around 600 degrees.
In addition, the commercial glass optical fiber is consisting of 3 parts, core(pure silica) cladding(doped silica),and buffer layer(polyimide). The company says that this fiber can endure even at 400 degrees because of the polyimide, which is heat-resisting polymer. But, I think that it can endure up to 600 degrees if there is no polymer. Is it true? I will use the fiber as just a substrate, so I don't need any other layer except the core.
After I etch the polymer, what is the limit temperature for the glass optical fiber?
Using COMSOL I want to observe the self-image phenomena in singlemode-multimode-singlemode (SMS) fiber. But there is some problem that could be due to boundary condition. How to use boundary condition for this case?
We are trying to visualize stress rods in polarization maintaining (PM) optical fiber and so far we have used UV light source (310 nm) to visualize stress rods in PM fiber. The resulting image is not having much appreciable contrast difference. Is there any other way of doing this ?
I've made good optogenetic fiber implants for lasers in the past using lower numerical aperture (NA) silica core fiber from Thorlabs. Recently, we've been working with LEDs which require a higher NA fiber in the 0.6 - 0.7 range. The highest NA fiber that Thorlabs carries is 0.5. Prizmatics has the right silica core fiber with high NA, but they only have core diameters of 200um & 250um.
Does anyone know a good vendor for this kind of fiber ( bare fiber, silica core, ~0.65NA)?
I am looking for an optical fiber where the cladding is removed at one end (about 1cm long). I have read some papers that explain how to do it, usually with HF, but I would like to know if there are providers that offer this type of product. So far, I know Thorlabs doesn't offer it.
Thanks in advance!
We are exploring the fabrication of an optical coupler ( fused biconic taper type ), where 1 fiber is having 80 microns cladding diameter with a LP11 cutoff around 850 nm. The other fiber is a standard 125 microns cladding diameter SMF ( LP11 cutoff around 1250 nm). It is understood that the first fiber will be lossy at 1550 nm. My question is if we want to taper both of these fibers to say 10:1, what would be the problem with 1 of them having a much lower cutoff wavelength ?
Hello, i hope you are doing well, i want to know how the etching of the cladding of an optical fiber is done in a controlled way, does anyone have a method or know somewhere i can do that ?
I am using Quick View mode of the Ocean View software for Ocean FX spectrometer.
When I check the Dark Spectrum (taken when the fiber inlet is closed and the Spectrometer is covered with Black cloth and the Background Spectrum is when the Optical fiber is placed when no source is there, only ambient light is ON.
I would also like to know why there is a dip around 550 nm?
I would like to calculate the Mode Field Diameter of a step index fiber at different taper ratios. I understand that at a particular wavelength, the MFD will be decreasing as the fiber is tapered. It may increase if it's tapered more. I am looking to reproduce the figures ( attached ) given in US Patent 9946014. Is there any formula I may use ? Or it involves some complex calculations?
Most of the authors presented their work on Mach-Zehnder modulator in fiber optic communication. When I saw Mach-Zehnder Modulator on internet for buying it is showing it with fiber optic cable both sides of Mach-Zehnder Modulator(input and oupt side). My question is that can we use Mach-zehnder modulator for intensity modulation in wireless optical communication? Please help.
I want to calculate the propagation constant difference for LP01 and LP02 modes for a tapered SMF-28 (in both core and cladding).
Is there a simple formula that I can use? My goal is to see if the taper profile is adiabatic or not.
I am using this paper for my study : T. A. Birks and Y. W. Li, "The shape of fiber tapers," in Journal of Lightwave Technology, vol. 10, no. 4, pp. 432-438, April 1992, doi: 10.1109/50.134196.
equation in attached figure
In my experiment I have a double cladding fiber spliced on to a reel of SMF-28. The double cladding fiber has total cladding diameter about 2 times more than that of the SMF-28. The source is a SLD, and there is a polarization scrambler after the source which feeds onto one end of the reel of SMF-28. The output power from the 1 km long reel is X mW. But when I splice a half meter length of the specialty fiber to the reel output and measure the power it is 0.9Y mW, where Y is the power output after the polarization scrambler (Y = 3.9X). I am not sure why the power reading suddenly increased.
My set up is as follows : Elliptically polarized light at input -> Faraday Rotator -> Linear Polarizer (LP) -> Photodiode
The LP is set such that the power output is minimum. I use a lock -in-amplifier to measure the power change due to the Faraday effect. I have a more or less accurate measurement of the magnetic field and the length of the fiber. The experimental Faraday rotation (Rotation Theta= Verdet constant*MagneticField*Length of fiber) , is more than the theoretical prediction, so I was wondering if I am observing the effect of elliptical polarization at the input to the system.
As we know, when we get a type of fiber from a company, we can get a few dispersion parameter D at corresponding wavelengths( lambda).so we can also get the dispersion slope dD/d_lambda.
Then how can we get the value of 4th disperison beta_4 with the value of D and dispersion slope dD/d_lambda?
Many of the research papers I looked through have the laser or light source at one end of the fiber optic cable and a detector at the other end. But I wanted to know if there was any research on how we could transmit light through the cladding so that it propagates both ways to the two ends of the fiber optic cable?
One idea that I had was to polish off the cladding at the middle of the fiber cable so that the core is exposed. Then point the light source at the middle exposed core so that the rays pass to both ends. But I wanted to know if there was any other way to do this without altering the fiber?
I need to simulate a setup like in the attached image. The source of light is the end of an optical fiber. In order to avoid simulating the fiber, I though about using a lens with the same NA as the optical fiber.
Any ideas/suggestions are welcome!
I'm curious if anyone can share their measurement of the coupling loss as a function of the gap between two SMF FC/APC fibers at various wavelengths. If not, it would be great if you can refer me to a datasheet or a paper where this type of measurement was done.
Is there any company that sell Yb-doped fiber with core diameter larger than 90 micrometer?
if anyone know please tell me about it.
I'm calculating the mode overlap between my Spot Size Converter (SSC) and an optical fiber (SMF-28, NA = 0.14) in Lumerical FDTD using the Mode Expansion Monitor and Linear DFT Monitor. At the same time, I'm comparing the result with the Mode Overlap Integral of SSC (fig is attached).
The difference value is too much (~20% of difference) and I would like to know if by using the Mode Expansion Monitor the mode overlap calculation is similar to the model attached. The model attached is found in many papers and to use it I simply export the E fields calculated by Lumerical (the SSC and optical fiber E field) and import them in matlab to calculate the Mode Overlap between the fields.
Does anyone know the difference and which would be more accurate?
I built a optical fiber probe (one emission surrounded by six for collection, no filters) and I wish to capture Raman spectra.
The lasers I have available to me are at 976nm but they do have a lot of power (>4W), however, I don't seem to be able to measure any Raman signal.
What might I be doing wrong?
The aim is to characterize a DAS instrument connected to a fiber optic cable.
what are the properties that I should look into ? white noise ? Dynamic range? SNR ?
I did some choc tests and I'm thinking on how should I calculate the SNR. Should I calculate a SNR for different frequency band ?
Thank you in advance,
If I reduce the dimensions of an optical fiber through a tapering process, I expect high losses of confinement. I am wondering:
1) If I recoat the fiber (after the tapering process) with a low-index external coating (lower refractive index with respect to the cladding refractive index), will I expect high internal reflections?
2) Otherwise, due to the extinction coefficient of the coating, could I consider the power losses absorbed by it?
What is the right behavior of external fiber coating?
I tried methylene chloride and chloroform for several days, but they didn't work.
The information of optical ferrule and optical fiber:
We are measuring vegetation (grassland canopy) reflectance with a handheld spectrometer, using the sun as the light source. When taking white reference measurement Is it important that the distance from the optical fiber to the white reference standard is the same as the distance from the optical fiber to the sample (grassland canopy)?
Eg. Our optical fiber has a 30 degrees field of view (FOV), which would mean a ground footprint of about 0.25 square meters when holding the optical fiber at about 1m above the grassland canopy. We can use a small diameter ( 50 mm) white reference standard held close to the optical fiber end (to cover the whole FOV) or we could get a large diameter white reference standard (wide enough to cover the 0.25 square meters FOV) that we hold at grassland canopy level- 1m below the optical fiber.
I was searching for a bragg Grating simulation example in comsol, but I did not find any. The only one that I found was incomplete. Does anyone have a Bragg Grating simulation example in comsol? It can be the file or even a tutorial of the simulation.
How would the spectrometer signal change if the target molecule was well dispersed in a solution and placed on the fiber optic SPR cable VS the target molecule concentrated at a specific region on the fiber optic cable?
I am using a Blue-Wave spectrometer with an optic fiber that has a field of view (FOV) of 30 degrees to measure the reflectance of the crop canopy.
If I hold the fiber optic cable approximately at 1.25 m above the canopy for reflectance measurements, I have a ground footprint of 0.27 m in diameter.
What happens with the footprint diameter if I attach to the optic fiber a fore optic: a collimating lens (LENSQ-COL, StellarNet) that has FOV 3 degrees, an 5 mm diameter?
Does intensity of light used in OFC, effect the data rate and bandwidth provided by the OFC? If yes, should we need increase the intensities of light that is currently being used? Also by increasing intensity of light, the power and energy density carried by the light increases and does that heat up surface of the OFC (core and cladding) and should we consider such factors in improving the technology or while working with OFCs?
I am carrying out research on MCF - MDM based optical transmission line performance analysis
The rays concentrated by convex lens is passed through 1m optical fiber. But only the ray enter into optical axis reaches fiber end, other rays are not? Can anyone suggest where i went wrong?
In our current era there is a big confusion about the usage of G.652 and G.655 optical fiber cable.
Theoretically G.655 is much better than G.652 but the operator feel that G.652 is giving almost same performance while the cost is quite less.
Anyone having direct experience please share your feedback, also I will soon be making a survey on it, so if anyone is interested in the survey then he can let me know.
What is the reason of the received optical signal to be slimmed down in multi-mode fiber?
I have 4 km multi-mode fiber
We have observed large fluctuations in laser power in our setup and traced them down to fluctuations in laser beam polarisation. Attached is a schematic of the relevant part of our setup. We have experienced large fluctuations in laser intensity at the sample (after the microscope objective). Attached is a plot of laser power measured at the sample plane. We have checked the laser itself and its output power is stable. We have checked also the laser power at the exit of the optical fibre collimator (before the polarising beamsplitter) at different time points (when the power after the objective was around its maximum and when its was around its minimum) and it remains stable as well. From that we concluded that it is the plane of the polarisation that is changing in time. We have then checked the laser alone and this time placed a polariser between the laser and the power-meter. The power is still stable, showing that the polarisation of the laser output is stable in time. So there's nothing wrong with the laser itself.
Do you have any idea what could be the source of those fluctuations? I know that reflection of laser beam back to the cavity can destabilise the laser, but can this make the plane of polariation rotate? And can it happen on such a slow timescale? Thanks for your answers.
Hello dear researchers.
I want to solve a cylindrical waveguide, lick an ordinary standard optical fiber. I am familiar enough with the 2D-axis-symmetric model, but as I knew from the equations and output results (if I'm right) 2D-axis-symmetric models just solve the symmetric model in relation to the r=0 axis, and a simple revolve node, in the dataset, revolves the whole answer around the r=0 axis, and if the coordinate is not defined earlier, you may achieve only a revolved data where the data is multiplied by 2*pi.
Now, if I define a new coordinate system, particularly I mean it for electromagnetic waves, is it possible to introduce the 2D-axis-symmetric model to solve such vector-based problems properly???
Thank you in advance.
Hi. I am new to chromatic dispersion related work and have read how it affects the shape of optical pulses. I want to ask how does it work for analog continous wave laser signal? why all books only mention laser pulses and pulse broadening of digital signals. what about using analog CW laser and modulating analog IF signals on it. How will CD affect it through pulse broadening . . . secondly, books mention that CD is a linear process. Is it because the pulse broadening factor equation has only L (not L square?) because the GVD equation contains lambda square (square of wavelength or frequency). how is it a linear process then? thanks a lot
Please recommend the optimal optical component and its parameters.
Thanks a lot
I am working on my diploma thesis regarding eye endoscope. I would like to know more about the speckles in the multimode fiber. I would like to reduce speckles in MM fiber using vibration. I do not know why the vibration reduce the speckles and what happens with modes that are in the optical fiber.
Thank you for your answer!
I would like to make an Fabry-Perot cavity without welding or adhesvie.
I am working on my diploma thesis regarding eye endoscope. I would like to know more about the origin of speckles in the multimode fiber. I suppose that the speckles depend on fiber modes but I do not know why should high-order modes move with higher speed than low-order modes. And how does this fact influence the speckles.
Thank you for your answer!
I'm looking for a company that provides square core optical fiber at a relatively low cost. Core size I need is ideally 1000 um x 1000 um (or as close as possible). So far optoskand has it but its $475 per meter so anything less expensive than that would be decent. It doesn't need to be connectorized either just the fiber.
For a special research project, we are looking for high temperature resistant optical fiber. A PPT document is attached in this mail to explain our application more precisely. Ideally, we are looking for an optical fiber that can withstand up to 1000-degree celsius.
Other specifications: - Approximate Length of optical fiber- 2m - Working temperature- 700°c- 1000°c - Approximate wavelength range - 200nm-1200nm - Mode type - Single-mode
Is it able to find these high temperature resistant optical fiber??
If it is, can you please help me to find this high temperature resistant optical fiber?
(Any specific companies offering these high-temperature optical fibers??)
Thanks in advance!!!!
Looking forward to your response.
Best regards, Vayalthota Gopikishore
I have a divergent beam coming from a sample in the NIR region. I need to converge the light into a fiber and take the spectrum. A rough sketch of the set up is attached here. Could some please suggest on how to select the specifications of the lenses and the optical fiber so that the emitted radiation is effectively coupled into fiber.
I am planning to concentrate the sunlight using the Fresnel lens onto the fiber optic cable for my indoor experiments. But I am thinking that I will face the following problems:
1. The aperture of the fiber optical cable is very small. Can it hold and transmit all concentrating light rays as optical cables have a particular angle of acceptance?
2. The magnitude of concentrated light is approximately 1000 x 1000 W/m2. Can the cable sustain the high temperature produced by the concentrated beam and transfer the sunlight from one place to the another?
3. What are the losses occurred in transporting the light along-with their magnitudes?
4. What is the maximum distance traveled by the concentrated light beam through the optical cable?
5. Where can I purchase the concentrated fiber optic cable from and how much does it cost (approximately)?
I will be thankful to you if you answer any of the aforementioned questions.
During the process of inscription of FBG on the silica/glass optical fiber few centimeters of the fiber had to be stripped. Bare fiber is too fragile for mechanical measurements, so I thought about recoating it. Unfortunately - I don't have an access to a recoater.
Is there any chemical solution I can use for DIY recoating purpose?
I am in the process of acquiring equipment for a second in vivo electrophsyiology rig, and I can't seem to find who produced the cannula holder that we use on our other rig. We want to be able to position multiple optic fibers simultaneously while recording, and the tapered and elongated construction of the cannula holder that we have now is ideal.
Does any one know who produced the cannula holder in the images attached?
As we all know, if an optical fiber is designed with the right material and properly bent, light can be transmitted along the fiber with very little attenuation.
Figure 1 shows the interaction of radiation F with a conical structure. The cone is a hollow mass with an internal reflector layer or a homogeneous mass of transparent material. Due to the non-ideal incident angle of radiation F (as shown in figure 1), radiation F will be easily reflected back or transferred out of the cone.
In the case of the above cone is a system of multiple optical fibers (figure 2). Optical fibers are arranged as a multi-branch tree: Start by an optical fiber at the bottom, then it is gradually branched at the upper rows and the top row will have the most fibers. Optical fibers have one narrow end below and the other larger end above. The optical fibers are separated by a vacuum layer so that total internal reflection can occur optimally. It can be noticed that radiation F will be easily transmitted along the fiber inside the cone.
We find that with the same incident angle and interaction position, radiation F in the two figures will have two different directions. It can be seen that a system of multiple optical fibers will have a much larger acceptance angle.
The key is to find the right material for the fiber and bend the fibers properly (without bending too strongly) so that radiation F is not refracted out of the fiber during transmission.
Extending from radiation F, can we use the above multiple optical fibers system to optimize solar energy harvesting (similar to Winston cones or Fresnel lenses but with higher efficiency)?
I am trying to find out Young's modulus of an optical fiber. I am not sure which two points should I use to calculate young's modulus? Should I calculate it from initial point? or any two points from linear region is okay? I have two linear region and I am confused which part should I take into consideration?
Could anyone help me?
How to design a rectangular step-index optical fiber using Comsol Multiphysics Software
I have a task to simulate optical beam profile from skewed optical fiber tip.
Can Zemax simulate it ?
Fiber SMF28. Skew angle 8 degree. Wavelength 1500 nm.
In many optical fiber papers, authors report the refractive index difference (Δ n) instead of the absolute refractive indice. As a material scientist, sometimes I need the absolute values of the core and cladding materials to do some calculations. This troubles me a lot, some papers have the exact material I'm intrested in, bu they only provide the RI differences (Δ n), not the absolute values. Is there a way to get the absolute values from the known Δ n?
A fiber Bragg grating consists of a periodic modulation of the refractive index in the core of a single-mode optical fiber. These types of uniform fiber gratings, where the phase fronts are perpendicular to the fiber’s longitudinal axis with grating planes having constant period
I am going to conduct experiment on sunlight collection. First the sunlight is collected using Fresnel lens. Then the concentrated light is transported via silica optical fiber. Since the concentrated sunlight is so bright its very difficult to look through naked eye. Can anyone suggest a good protective eye wear to do this experiment? Somewhere i read welding glass is enough. Is it so?
Can anybody suggest a resource which includes the modeling of pulse propagation in optical fiber using split step fourier method and model the nonlinear optics theories in the book nonlinear fiber optics by G.P.Agrawal? If there is a basic course ,a lecture series or a book in computation optics, please do recommend it.
The input beam is launched to the fiber. It is scattered inside the fiber and not reaching to the other end of the fiber. The problem could be due to the boundary condition. How to use boundary condition at the input and output face of the fiber ?
I'm interested in directing as much light as possible from the LED into the SMA-terminated optical fibre. What sort of adaptor or bushing would I need to be able to connect the LED to the fibre? I am using Osram SFH 4725S for the NIR LED and a lab-grade patch cord from Ocean Optics.
I want to insert a metal probe into the body. This probe is a metal enclosure that contain of an optical fiber. The light comes out of the fiber end and through the hole in the end of the tube. I want to paste the optical fiber to the metal enclosure with a transparent biocompatible adhesive. What is the best adhesive for this work? This adhesive should to be resistant to disinfectants agents.
I need to reflect exited beam from optical fiber to 90 degree in a narrow path as shown in attached figure. The path is circular with 2 mm diameter and 10 mm length. I need to reflect beam in just one direction! For example Z direction!
How can I do it?
I need to coupling a 250mW laser diode source light into a 1.5 mm multi mode optical fiber. I have done it with a double convex lens. But, I have a lot of dissipation! How I can coupling laser diode light into the optical fiber without dissipation? I need to receive 250mW output power from the end of the fiber!