Magnetic Sensors Based on Fiber Optic Products Detect Very Weak Magnetic Fields

magnetic FBG sensorsA light-based technique for measuring very weak magnetic fields was recently developed by researchers at the University of Arizona. A portable, low-cost brain imaging system based on fiber optic products can operate at room temperature in unshielded environments. This fiber optic system would allow real-time brain activity mapping after potential concussions on the sports field and in conflict zones where the effect of explosives on the brain can be catastrophic.

Speaking specifically, scientists and engineers fabricated the magnetic sensors using optical fibers and a polymer-nanoparticle composite that is sensitive to magnetic fields. The researchers selected for their project nanoparticles based on magnetite and cobalt. These materials exhibit very high magnetic sensitivity. The aforementioned magnetic sensors can detect the brain’s magnetic field, which is 100 million times weaker than the magnetic field of Earth. Also, the researchers showed that new magnetic sensors can catch the weak magnetic pattern of a human heartbeat and has the capability to detect magnetic fluctuations that change every microsecond from an area as small as 100 square microns. Multiple seasons could then be used together to provide high spatial resolution brain mapping.

During work, the polarization rotation using an optical interferometer was detected. This works by splitting laser light into two paths, one of which passes through the highly-sensitive material while the other does not.

Indeed, further development of the researchers will be aimed at the long-term stability of magnetic sensors. Scientists plan to study how well sensors withstand environmental changes. Plus they want to fabricate several hundred sensors to make a special fiber optic system for evaluating and imaging the entire magnetic field of a human brain.

The newly developed magnetic sensors could help scientists better understand the activity of the brain and diseases of the brain such as dementia and Alzheimer’s. They might also be used to predict volcanic eruptions and earthquakes, identify oil and minerals for excavation, and detect military submarines. In addition to this, such magnetic sensors could offer an alternative to the magnetic reasonable imaging (MRI) systems currently used to map brain activity without the expensive cooling or electromagnetic shielding required by MRI machines.

Optromix is a fast-growing seller of such products from the fiber Bragg grating (FBG) line of products: fiber Bragg grating sensors, FBG interrogators, and multiplexers and, of course, Distributed Temperature, Acoustic, and Strain Sensing systems (DTS). Our major goal is to deliver the best quality of fiber optic sensors to our clients. Optromix creates and supplies a broad variety of excellent fiber-optic solutions for the monitoring of various facilities all over the world.

If you are interested in Optromix fiber optic products, please contact us at info@optromix.com

 

 

Fiber Optic Equipment Goes Biocompatible and Implantable thanks to Hydrogel Fibers

FBGs used in hydrogel fibersA biocompatible and highly stretchable optical fiber made from hydrogel may be implanted in the body to deliver therapeutic pulses of light or light up at the first sign of disease. This hydrogel fiber was developed by researchers from MIT (Massachusetts Institute of Technology) and Harvard Medical School. Hydrogels have already shown significant potential in everything from wound dressings to soft robots, but until now their fiber optic applications have been limited from their lack of toughness. Hydrogels are made of hydrophilic polymer chains that absorb up to 90 percent water. Such fiber optic products aren’t very strong or durable, but by adding glass tiny fibers the researchers created a tough, bendable, stretchable material.

In other words, a hydrogel is an extremely absorbent type of gel, a network of simple polymers that can contain up to 99,9% water, by weight. As the walls of this hydrogel, the material lining the interior of an optical fiber is clear but tuned to produce a phenomenon called total internal reflection. This means that light that moves at certain angles from the cable’s core material to its lining will be entirely reflected. By tuning hydrogel to create the same effect, scientists and engineers from MIT created a form of biocompatible optical cable. Getting light into the body is important: in the most basic sense, pulses of light are information, and having a hard-wired line of communication to implanted technology will be essential for development. However, it should be noted, such a wireless technique is still too unreliable for most people to bet their lives on, and it’s also notoriously hard on power consumption.

The researchers say that fiber optic products may serve as a long-lasting implant that would bend and twist with the body without breaking down. The researchers also have devised multiple recipes for making tough but pliable hydrogels out of various biopolymers. Plus the team has come up with ways to bend hydrogels with various surfaces such as metallic sensors and LEDs. Each optical fiber transmitted light without significant attention or fading. These fiber optic devices also found that fibers could be stretched over seven times their original length without breaking. Such modern fiber optic products can be used for long-term diagnostics, to optically monitor tumors or inflammation.

In other words, hydrogel fibers are interesting and provide a compelling direction for embedding light within the human body. Only considerable efforts in optimizing and managing the physical and mechanical properties of fibers will enable practical applications of medical relevance.

Optromix is a fast-growing vendor of fiber Bragg grating (FBG) products line: fiber Bragg grating sensors, FBG interrogators, and multiplexers, Distributed Temperature Sensing (DTS) systems. We create and supply a broad variety of top-notch fiber optic solutions for the monitoring of various facilities all over the world.

If you are interested in Optromix fiber optic products, please contact us at info@optromix.com

Fiber Optic Products Key to Optimised Fully Implantable Hearing Aids

FBGs for hearing aidsModern research allows creating more and more biocompatible and highly stretchable fiber optic products. The optical fiber may one day be implanted in the body to deliver therapeutic pulses of light up at the first sign of disease. The world’s healthcare providers are increasingly looking to advanced biomedical instrumentation to enable more efficient patient diagnosis, monitoring, and treatment. Fiber optic equipment can be used in humans (clinical), in animals (veterinary), or other living organisms (life sciences), and, depending on the intended use, can be for diagnostic, therapeutic, or intensive care uses in clinical applications, research, and preclinical development, or laboratory testing.

The joint Austrian-Serbian team is moving closer to developing a fully implantable hearing aid. The technology is based on completely contact-free fiber optic equipment that senses the tiniest ossicle movements and use them to stimulate the acoustic nerves. The weak spot of the fully surgically implantable hearing devices is the microphones, which receive sounds and use a sophisticated process to transform them into impulses for the acoustic nerves. It is important that such microphones can function error-free inside the human body for many years. Nowadays this is only possible to a limited extent, so now solutions are urgently needed.

New fully implantable hearing aids can overcome a wide range of patient’s problems. Even state-of-the-art hearing aids often require parts outside the ear. This has many disadvantages for people who wearing hearing aids. For example, parts of the ear often become inflamed and the wearer’s own voice sounds distorted. Plus traditional hearing aids can be stigmatized if the device is visible.

The use of contact-free fiber optics measuring devices to detect sounds is the one highly important advance. Such fiber optic products would allow the microphone to be positioned inside the ear. This technology is based on low-coherence interferometry, a method which picks up superimposed sound waves. The ability to pick up sound from the ossicles is a huge advantage because it fully preserves the natural amplification function distortion and feedback.

The team of Austrian-Serbian scientists needed to address a number of fundamental requirements. For instance, they had to develop the operative procedure for the implantation, as well as the means of “targeting” the laser used for sensing. In the process of research scientists used artificial and animal models, which allowed them to optimize the quality of the ossicle vibration sensing system. The recently published findings confirm the effectiveness of the technology and that, in principle, could be used inside the ear for long periods. Aspects such as system miniaturization and electricity consumption will also be addressed by the team.

Optromix is a fast-growing seller of such products from the fiber Bragg grating (FBG) line of products: fiber Bragg grating sensors, FBG interrogators, and multiplexers and, of course, Distributed Temperature, Acoustic, and Strain Sensing systems (DTS). Our major goal is to deliver the best quality of fiber optic sensors to our clients. Optromix creates and supplies a broad variety of excellent fiber-optic solutions for the monitoring of various facilities all over the world.

If you are interested in Optromix fiber optic products, please contact us at info@optromix.com

Advanced Fiber Optic Solutions Further Biomedicine

FBGs for biomedicineNowadays the production of optical fibers is robust and flexible enough to address an exciting new range of biomedical applications. Fiber optic applications in general and they are in biomedicine have gained momentum in recent years. The optical fiber has been used primarily for endoscopy and laser power delivery, but now a wide base of academic and corporate-funded studies is exploring both in vivo and in vitro areas, with a number of new applications entering full-scale manufacturing. This growth has been fueled by a list of capabilities, including entering fuel-scale manufacturing. This growth has been fueled by a list of capabilities, including:

  • electromagnetic interference (EMI)-free transmission of energy and signals
  • small diameter
  • biocompatible coating
  • high mechanical flexibility
  • image transmission
  • the ability to sense pressure, temperature, chemicals, and strain.

The great capabilities suggest the introduction of fiber optic products in a wide range of applications. Such a broad range of applications requires a wide selection of fiber optic products with designs ranging from large-core, large-diameter multimode (MM) optical fibers for high-power laser light delivery to small-core, reduced-diameter single-mode (SM) optical fiber for in vivo sensing. Additional requirements demand advanced coatings because special coatings enable reduced thickness and greater tolerances: polyimide, for instance, in contradistinction to an acrylate, can withstand temperatures up to 300ºC as well as autoclave sterilization.

Device miniaturization is required for in vivo applications: fiber optic products and based on the fiber optic systems typically need to localize within a catheter tube where typical sizes for surgical procedures, such as coronary angioplasty, range from 5F to 8F (1473-2286 μn diameter). A standard optical fiber with a 245 μm coating diameter can fit within this catheter space, but it will need to accommodate other devices as well, including guide wires and manipulation tools. Beyond dimensions, an optical fibers stiffness must be considered as it can impact the flexibility of the overall catheter assembly, affecting the ability to guide the catheter correctly.

It is important to note that fiber optic products do not contain any electrically conductive or magnetic materials. Any fiber optic equipment can be considered free from electromagnetic interference (EMI). In other words, fiber optic products can be used in magnetic resonance imaging (MRI) devices and in close proximity to radiofrequency (RF) electrosurgery tools used for cutting, coagulating, desiccating, and fulgurating tissue. Alternative techniques require an electrical sensor element, making them not only unsuitable for MRI and RF use but also require a separate signal line for each sensor element, which adds to the cross-sectional area. Fiber optic solutions, in contrast, imply thousands of uniquely identifiable sensor elements and still require only the single line of fiber, without additional sacrifice to the diameter. This characteristic enables the transmission of multiple messages along one channel of communication. Such transmission often uses specially modified regions of the core called fiber Bragg gratings (FBGs).

In addition to this, one of the most impressive up-and-coming biomedical applications of fiber optic products is that of 3D shape sensing to facilitate procedures such as coronary angioplasty with minimal use of x-ray-assisted guidance. 3D shape sensing and distributed in vivo pressure sensing were not feasible, but optical fibers have made them possible.

Additionally, fiber optic devices have traditionally been developed and sold primarily for high-power laser applications. But their new generation and exactly a new generation of fiber optic probes allow both outputs of light in a particular format and collection of reflected light back into the optical fiber.

Optromix, Inc. is a U.S. manufacturer of innovative fiber optic products for the global market, based in Cambridge, MA. Our team always strives to provide the most technologically advanced fiber optic solutions for our clients. Our main goal is to deliver the best quality fiber optic products to our clients. We produce a wide range of fiber optic devices, including our cutting-edge customized fiber optic Bragg grating product line and fiber Bragg grating sensor systems. Optromix, Inc. is a top choice among the manufacturers of fiber Bragg grating monitoring systems. If you have any questions, please contact us at info@optromix.com

 

 

How to Make Surgery Less Invasive with the Fiber Optic Products Help?

FBGs for less invasive surgeryOptical fibers have the potential to be used in many biomedical applications. Such fibers have been used in medical devices since the 1960s when fiber optic bundles were successfully pioneered for both illumination and imaging through endoscopes. Optical fiber imaging tools were widely accepted for invasive surgery since the 1980s. The minimally invasive surgery promises decreased pain and trauma during operations, faster recovery, and a reduced risk of infection. Nowadays special fiber optic products also are used as intelligent sensors to monitor physiology parameters such as temperature, pressure, oxygen concentration, and applied force.

Fiber optic sensors offer many advantages in comparison with conventional electronic sensors in medical sensing: small size, immunity to electromagnetic interference (EMI), enhanced sensitivity, robustness, and geometrical versatility. Additionally, they are free from electrical parts or conductors in the sensor area. The unique properties of fiber optic products and based on the fiber optic equipment have enabled complicated procedures in cardiovascular examiners, angiology, gastroenterology, ophthalmology, oncology. neurology. dermatology, and dentistry. Novel specialty fiber types are also opening up entirely new sensing concepts. In addition to this, endoscopes represent the largest end-use market for medical fiber optics, supported by the growing popularity of minimally invasive surgeries. Minimization of medical instruments is a key trend encouraging the use of small and efficient optical fibers.

The integration of fiber optic applications in medical devices is a difficult task because it involves solving such problems as design and selection of fiber, packaging material, cost-effective manufacturing, quality control, and traceable record keeping.

In the last two decades, a variety of fiber optic products have been developed. However, it should be noted, point sensors based on Fabry-Perot interferometers and fiber Bragg gratings (FBGs) are probably the most deployed sensors in medical applications.

Fiber optic products and based on the fiber optic sensors are safe, valuable, highly stable, biocompatible tools for health-monitoring systems and they are amenable to sterilization and autoclaving. By modifying properties such as numerical aperture, core and cladding diameters, and coating material, the fibers can be adapted to different applications.

Why do fiber optic products find so many biomedical uses? Firstly, optical fibers, which used in medical sensors, have a thin polyimide coating to provide a small section and suitability for different kinds of sterilization processes. The temperature resistance of polyimide is difficult to match with other polymer materials. Secondly, the highly desirable parameter of the optical fiber for invasive surgery is tolerance to tight bonds. This allows for movement of the catheter, which winds through veins and arteries, and around organs and bones, on its way to an application area.

Summing up all of the above, the biomedical sensing market represents a lucrative and growing opportunity for fiber optic sensors, particularly for large volumes of disposable probes. The demand for move patient monitoring devices combines with a trend toward minimally invasive surgery, which itself requires a variety of small size that can be incorporated into catheters and endoscopes. There is also an opportunity for fiber optic sensors as EMI-compatible sensors to monitor vital signs during the use of MRI (and related techniques), as well as RF treatments.

Optromix is a fast-growing vendor of fiber Bragg grating (FBG) products line: fiber Bragg grating sensors, FBG interrogators, and multiplexers, Distributed Temperature Sensing (DTS) systems. We create and supply a broad variety of top-notch fiber optic solutions for the monitoring of various facilities all over the world.

If you are interested in Optromix FBG sensors or other fiber optic products, please contact us at info@optromix.com

 

Advances in Manufacturing Fiber Optic Gyroscopes

FBG sensors for gyroscopesMeasurement of angular velocity is useful in many different applications, from missile navigation to motion control. There are three broad categories of possible sensors for angular velocity: Ring Laser Gyroscopes (RLG), Fiber Optic Gyroscopes (FOG), and MEMs-based Gyroscopes. The former two utilize the Sagnac effect to measure velocity and are much more sensitive compared to MEMs gyroscopes. A fiber optic gyroscope (FOG) is a  device that senses changes in orientation using the Sagnac effect. Such a fiber optic device performs the function of a mechanical gyroscope. However, it should be noted, its fiber optic solution is instead based on the interference of light which has passed through a coil of optical fiber that can be as long as 5 km.

What is the principle of the fiber optic gyroscope? Two laser beams are injected into the same optical fiber but in opposite directions. The beam that moves against the rotation experiences a slightly shorter path delay than the other beam due to the Sagnac effect. The resulting differential phase shift is measured through interferometry. This phase shift translates one component of the angular velocity into a shift of the interference pattern which is measured photometrically. The strength of the Sagnac effect is dependent on the effective area of the closed optical path: this is not simply the geometric area of the loop but is enhanced by the member of turns in the coil.

Victor Vali and Richard Shorthill demonstrated an operational fiber optic gyroscope for the first time in 1976. In that same year, McDonnell Douglas Astronautics Co. in Huntington Beach, CA, completed a project to redesign a new, lower-cost inertial measurement unit for the Delta rocket based on dry-tuned mechanical gyros. The technology supporting early efforts in the field of fiber optic gyroscopes were fiber optic products derived from the Sagnac interferometer. The first sensor of this type was the Sagnac acoustic sensor. Another derivative sensor is the Sagnac strain sensor. Nowadays, the Sagnac interferometer continues to be a useful tool for a variety of sensing and communication applications. One principal advantage of the Sagnac acoustic and distributed sensors is that they can be supported by very low-cost single-mode optical fiber. This opens up a number of interesting applications, including identifying leaks in pressurized pipes and containers, identifying the location of insects in grain storage facilities, and locating termites in wood.

Fiber optic gyroscopes are robust apparatus for measuring angular velocity. It is interesting that fiber optic gyroscopes are instruments where merely improving the processing of the incoming sensor signal can yield more stability, linearity, and sensitivity.

Optromix, Inc. is a U.S. manufacturer of innovative fiber optic products for the global market, based in Cambridge, MA. Our team always strives to provide the most technologically advanced fiber optic solutions for our clients. Our main goal is to deliver the best quality fiber optic products to our clients. We produce a wide range of fiber optic devices, including our cutting-edge customized fiber optic Bragg grating product line and fiber Bragg grating sensor systems. Optromix, Inc. is a top choice among the manufacturers of fiber optic devices. If you have any questions, please contact us at info@optromix.com

Fiber optics for Telecommunications

FBGs in telecommunicationsThe uses of optical fiber today are quite numerous. With the explosion of information traffic due to the Internet, electronic commerce, computer networks, multimedia, voice, data, and video, the need for a transmission medium with the bandwidth capabilities for handling such vast amounts of information is paramount. Fiber optic devices, with its comparatively infinite bandwidth, has proven to be the solution.

Fiber optic products are a major building block in the telecommunication infrastructure. High bandwidth capabilities and low attenuation characteristics of fiber optic devices make it ideal for gigabit transmission and beyond. The growth of the fiber optics industry over the past five years has been explosive. Analysts expect that this industry will continue to grow at a tremendous rate well, into the next decade and beyond.

The telecommunications industry is made up of many types of companies at different levels within the industry. These companies make products and/or provide modern technology (VoIP, CATV, HDTV, security, and suchlike) to the end-user (residential, business, and institutional).

Fiber optic systems have many advantages over metallic-based communication systems:

  • long-distance signal transmission
  • large bandwidth, low weight, and small diameter
  • nonconductivity (since optical fiber has no metallic components, it can be installed in areas with electromagnetic interference (EMI), including radio frequency interference (RFI)
  • security
  • designed for future applications needs

As the industry of fiber optic products continues to grow, frustrating bottlenecks in the “information superhighway” will lessen, which will in turn usher in the next generation of services, such as telemedicine, Internet telephony, distance education, e-commerce, and high-speed data and video.  

Optromix, Inc. is a U.S. manufacturer of innovative fiber optic products for the global market, based in Cambridge, MA. Our team always strives to provide the most technologically advanced fiber optic solutions for our clients. Our main goal is to deliver the best quality fiber optic products to our clients. We produce a wide range of fiber optic devices, including our cutting-edge customized fiber optic Bragg grating product line and fiber Bragg grating sensor systems. Optromix, Inc. is a top choice among the manufacturers of fiber Bragg grating monitoring systems. If you have any questions, please contact us at info@optromix.com

Advantages of the Application Fiber Optic Products on Aircrafts

FBGs in aircraft industryFiber optic products are revolutionizing the avionics systems and ideally to be the perfect solution to future requirements. A modern jet has enormous amounts of data flowing through it to support the latest technologies in the cockpit and the cabin. All that data has to be delivered at lightning speed. This necessity has led aircraft manufacturers and airlines to turn to the optical fiber. The copper cables co-existed with fiber optic applications for decades. Currently, designers and engineers find fiber optic products to make better sense technically and economically in the overwhelming majority of cases.

The ability of the optical fiber to transmit much more information in less time over longer distances than traditional copper wire has become the reason that fiber optic equipment is being deployed on aircraft. There are fiber optic bundles of copper cables in an aircraft and the signals which they carry are fully replaceable by fiber optic products to allow an improvement of the system in various different ways.

There are two common trends regarding data transmission in the avionics market: constantly growing transmission speeds and the need to reduce weight. Fiber optic systems are an ideal response to these two trends in providing for high-speed data and immunity to electromagnetic interference that eliminates the need for any type of screening which can often be very expensive due to their weight and complexity. Fiber optic equipment offers lower wastage, weight, size, etc. These advantages make fiber optic equipment suitable for application in aircraft where space restrictions and electromagnetic interferences could be detrimental.

Nowadays fiber optic systems have been implemented in different aircraft systems such as sensory systems, distributed opening systems, and fiber optic aircraft monitoring. In addition to this, other areas such as defense and space are upgrading their communication systems in production vehicles by incorporating fiber optic equipment. Fiber optic systems are likely to enjoy a bright future in aircraft requirements.

Optromix, Inc. is a U.S. manufacturer of innovative fiber optic products for the global market, based in Cambridge, MA. Our team always strives to provide the most technologically advanced fiber optic solutions for our clients. Our main goal is to deliver the best quality fiber optic products to our clients. We produce a wide range of fiber optic devices, including our cutting-edge customized fiber optic Bragg grating product line and fiber Bragg grating sensor systems. Optromix, Inc. is a top choice among the manufacturers of fiber Bragg grating monitoring systems. If you have any questions, please contact us at info@optromix.com

Fiber Bragg grating sensors: present and future applications in smart cities

FBG sensors in smart citiesThe so-called “smart cities” are increasingly becoming the subject of media discussion: nowadays the phenomenon of “smart cities” is the focus of attention of technology companies and entrepreneurs, local governments, and civil society. The primary task in creating and equipping “smart cities” is to improve the quality of life for citizens: such cities promise to be more modern and hi-tech.

Structural integration of fiber Bragg grating sensors and fiber optic sensor systems represents a new branch of engineering and is a major breakthrough in creating smart city infrastructures. Nowadays fiber Bragg grating sensors are a fundamental and indispensable component of any intelligent control fiber optic system. A well-functioning control system is generally equipped with an FBG array of sensors that allows this system to collect and process the required data about its environment. After data collection, the fiber optic system is able to fully characterize its environment and adjust its operations accordingly. The comprehensive capabilities of the fiber Bragg grating products present many opportunities that were unavailable in the past due to high costs and limited accessibility. It is necessary to emphasize that fiber optic systems and associated equipment provide the essential processing power for small-scale devices through which the coordination of the FBG sensors will be easy to implement at a relatively low cost.

Fiber Deployments and the Internet of Things

In itself, the fiber Bragg grating sensor is a converter that converts parameters of a physical nature to an electronic signal, which can be fed into an autonomous system or can be interpreted by humans. These FBG sensors can transmit information about light, pressure, temperature, humidity, moisture, and a variety of other parameters. More sophisticated fiber Bragg grating sensors include accelerometers for measuring acceleration and vibration. An even later generation of FBG sensors is based on semiconductor physics, nanotechnology, and intelligent sensing devices which include smartphones amongst others. Nanotechnology is a key enabling technology for fiber Bragg grating sensor development because advances in nanotechnology will undoubtedly drive development in MEMS (MicroElectroMechanical Systems) and photonics, inevitably leading to the development of highly sophisticated but low-cost sensors. Nowadays smartphones are fitted with a variety of sensors such as GPS, gyroscopes, accelerometers, and compasses, enabling a variety of crowdsourcing applications, which will eventually be augmented by the Internet of Things. In the context of the Internet of Things, the communication between sensors nodes has to be wireless because the costs of cabling millions of sensors are impractical and extremely expensive.

Fiber Bragg grating sensor systems can be compared to and are capable of being the nervous system of infrastructure as they are extremely sensitive to outside and environmental interference. A large variety of FBG sensors allows for extensive measurements of multiple parameters of many different buildings and facilities.

Advantages of Bragg sensors

One of the main advantages of FBG sensors is that they provide reliable data that allow for well-informed decision-making based on reliable evidence. Fiber optic systems allow for the assessment of thousands of sensors in real-time on a single cable. FBG sensor systems are well-suited for the detection and recording of critical structural response characteristics as well as environmental indicators that lead to degradation.

An alternative for Challenging Strain and Temperature Measurements

Optic sensing becomes one of the noticeable aspects, across multiple business sectors such as civil&energy, medical, automotive, aerospace, and manufacturing industries. The worldwide distributed optic temperature sensing market is majorly driven by the growing optics technology-based installation. Based on applications, the market has been segmented into temperature sensing, acoustic/vibration sensing, strain sensing, and others. The distributed temperature sensing segment is anticipated to dominate the distributed fiber optic products application arena (in the term by size) by 2025. There are already examples of the implementation of FBG sensors into smart city infrastructures.

Fiber Bragg gratings are often used in strain sensing especially in such places where the environment is harsh (for instance, high-EMI, high-temperature, or highly-corrosive). Strain measurement is imperative during prototype design and testing. Strain measurements ensure that materials perform as they should and that the equipment is safe and durable. Measuring strain is crucial for testing complex structures, like aircraft, turbines, etc. There various ways in which stress can be measured, but it is widely accepted that FBG sensors are the most efficient way of strain measurement.

The ability to disconnect your monitoring instrumentation and return for results after a large amount of time such as months or even years is a great advantage of fiber Bragg grating sensors. For instance, in the case of bridges, it is common for engineers to visit the bridge and conduct impact testing using an impact hammer on the different parts of the bridge. This is time-consuming and even hazardous because of the height of some bridge structures. The distribution of a number of FBG sensors throughout the bridge and the attachment of the instrumentation to this bridge on a periodic basis is a much more efficient solution. This is only one of the good examples to demonstrate the effectiveness of the fiber Bragg grating strain sensors. Besides bridges, other examples of using FBG for long-term static strain testing are buildings, piers, and structures in high earthquake-prone areas.

The different structures may have very-low-frequency modes, and they may also have higher modes due to the effects of wind and tide. Most earthquakes and other earth tremors are low-frequency events. Fiber Bragg gratings can be attached to the structures and monitored for the vibrations during earth tremors and earthquakes. The low-frequency dynamic strain testing can help in determining the reaction of high-rise buildings to the wind. In addition to this, FBG sensors create connections with peers and other shore structures to determine their vibrations during the ebb and flow of tides. Dynamic strain testing can also be performed on transportation vehicles like automobiles, trains, and airplanes. In addition to civil structures and vehicles, there are a number of other applications for dynamic strain testing and vibration stress testing using fiber Bragg gratings. FBG sensors can be attached to industrial machinery to determine the frequency and amplitude of the stress vibrations.  

More specifically, FBG strain sensors have been used in the following applications: performance monitoring of deep shafts and retaining walls; monitoring of deep diaphragm walls; assessment of tunnel lining behavior during tunnel construction; the FBG strain sensors are embedded in the precast concrete lining segments when being made in the factory; in-the-field testing of large diameter piles by integrating FBG strain sensors; monitoring of old tunnels during construction that happens nearby.

FBG temperature sensors are used for field testing of thermal piles in order to evaluate the thermo-mechanical response of piles during heating and cooling; monitoring the power lines to detect overstressed areas.

Where to buy the best fiber optic products?

Optromix is a fast-growing vendor of fiber Bragg grating (FBG) products line: fiber Bragg grating sensors, FBG interrogators, and multiplexers, Distributed Temperature Sensing (DTS) systems. We create and supply a broad variety of top-notch fiber optic solutions for the monitoring of various facilities all over the world.

Our main goal is to deliver the best quality fiber optic products to our clients. We produce a wide range of fiber optic devices, including our cutting-edge customized fiber optic Bragg grating product line and fiber Bragg grating sensor systems.

We are dedicated to delivering the best products and supports to all our customers, our engineers have extensive experience and strong technical expertise in creating fiber Bragg grating products.

If you are interested in Optromix FBG sensor systems, Optromix distributed acoustic sensing system, or any other fiber optic products, please contact us at info@optromix.com

Optical fiber temperature sensors and their applications

FBG temperature sensorsFBG sensors give the opportunity to measure a variety of parameters in conditions where other sensor technologies fail or simply cannot operate. Such FBG sensors have intrinsic advantages, including resistance to electromagnetic interference, non-electrical conductivity, passive measurements, small size and small weight, and the option of multipoint measurements. the reflection wavelength of the FBG (Bragg wavelength) depends on the grating characteristics (period, modulation) and is influenced by the ambient conditions such as strain and temperature. The development of fiber optic devices based on fiber optic sensors for operation in harsh environments (such as for temperatures of up to 1000°С) is becoming an increasingly important field. In the case of temperature sensing the Bragg wavelength is a function of the temperature. This temperature dependence results from changes in the refractive index of the fiber as well as from thermal expansion of the glass material. Many material properties show strong temperature dependence. Examples of such temperature dependencies are dew point, density, electrical conductivity, refractive index, rigidity, and diffusion. Temperature measurement also plays an important role in the health monitoring of electric circuits or civil structures.

The main advantages of FBG sensors are their measurement of reflected light, wavelength-encoded sensing, and multiplexing capability. Nowadays there are many types of FBG sensors used for measuring temperature: intrinsic and extrinsic.

Three major types exist:

  • The intensity-modulated sensors

Intensity-modulated FBG sensors are based on the principle of letting a physical disturbance such as temperature cause a change in the received light through an optical fiber;

  • The phase-modulated sensors

The phase-modulated FBG sensors are based on the principle of comparing the phase of light in the sensing fiber with a reference fiber in an interferometer;

  • The wavelength modulated sensors

Wavelength modulated FBG sensors are based on the principle that a physical disturbance such as temperature or strain changes the reflected wavelength of the light.

In general, it should be noted, phase modulated and wave modulated FBG sensors are providing much more accurate measurements than intensity-modulated sensors but at the cost of much more expensive interrogators.

Optromix, Inc. is a U.S. manufacturer of innovative fiber optic products for the global market, based in Cambridge, MA. Our team always strives to provide the most technologically advanced fiber optic solutions for our clients. Our main goal is to deliver the best quality fiber optic products to our clients. We produce a wide range of fiber optic devices, including our cutting-edge customized fiber optic Bragg grating product line and fiber Bragg grating sensor systems. Optromix, Inc. is a top choice among the manufacturers of fiber Bragg grating monitoring systems. If you have any questions, please contact us at info@optromix.com