Articles about Optics and Photonics, Lasers, Fiber Bragg gratings and FBG sensors

Continuous Wave (CW) Lasers and Their Applications

on July 17, 2018

There are three main categories of fiber lasers: continuous wave (CW) lasers, pulsed fiber lasers, and ultrafast lasers. Continuous wave lasers produce a continuous, uninterrupted beam of light, ideally with a very stable output power. The exact wavelengths or lines at which this occurs is determined by the characteristics of the laser medium. Each laser wavelength is connected with a linewidth, which depends on several factors: the gain bandwidth of the lasing medium and the design of the optical resonator, which may include elements to purposely narrow the linewidth, like filters or etalons.

The fiber laser has many important advantages by itself:

  • the output is naturally fiber-delivered, which makes it easy to couple into many laser machine tools and to integrate the easier with robotic delivery systems
  • fiber laser high beam quality is suitable to couple it into small fibers, allowing the beam to be focused to small spots in order to obtain the high power densities required for metal welding, cutting, and other industrial processes
  • fiber laser architecture lends itself to power scaling
  • such fiber lasers have high wall plug efficiency in comparison to CO2 and solid-state lasers, it can also have low maintenance requirements; this lowers the cost of ownership.

Must applications of continuous wave lasers require that the power be as stable as possible over long time periods, as well as over short time durations, depending on the specific applications. To ensure this stability also in the presence of varying environmental situations like temperature, vibrations, and the aging of the laser itself, microprocessor control loops are implemented.

Continuous Wave (CW) Lasers and Their ApplicationsContinuous wave lasers can be useful for a wide range of applications. Such fiber lasers and laser systems based on them are most often and for laser cutting, welding, and drilling tasks, which in itself see uses across dozens of industries. Continuous wave lasers are used in the aerospace and automotive industries to help cut, drill, and well anything from tiny thru-holes that keep engine parts cool, all the way up to cutting huge sheets of metal that form part of the vehicle or aircraft’s final structure. Such fiber lasers are most commonly used for industrial application, the majority of which involve metal in some form, continuous wave lasers find a high prevalence in being used to out, drill, and well metal. In addition to this, this type of the fiber laser is effective in being used upon a wide range of metals, including, but not limited to: steel, brass, nickel, aluminium, tungsten, and suchlike. Moreover, continuous wave lasers are excellent at working with reflective metals too. Such fiber lasers are actively used, additionally, in the medical sector, and it’s not only technologies that these machines are used for, these fiber lasers and laser systems are also used on people too. Powerful continuous wave is being used in trials by oil drilling companies to soften rock to extend the life of drilling heads.

Optromix Inc., headquartered in Cambridge, MA, USA, is a manufacturer of laser technologies, optical fiber sensors, and optical monitoring systems. We manufacture lasers using our own technologies based on the advanced research work and patents of international R&D team. Laser processes are of high quality, high precision, easily-automated manufacturing solutions that provide repeatability and flexibility. If you have any questions about continuous wave lasers please contact us at info@optromix.com

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ЕлизаветаContinuous Wave (CW) Lasers and Their Applications

Fiber Optic Products for Spacecraft Applications

on June 25, 2018

For the successful operation of any space mission, spacecraft monitoring is crucial. A variety of sensors are required to provide important information about the spacecraft health during fabrication, testing, and service lifetime. we have a lot to thank optical scientific instruments for ground-breaking climate research, satellites for observational systems, non-invasive medical research, and semiconductor production. Space is a challenging environment for any sensing system as it is characterized by microgravity, vacuum, the presence of radiation (protons, electrons, heavy ions, etc.), large thermal variations, mechanical vibrations and shock resulting from the launch. The specifications of sensors are derived by the type of mission primarily defined by the orbital altitude, the operational lifetime, and the location of the sensor in the spacecraft.

Fiber optic systems are considered for spacecraft applications due to many advantages such as intensivity to electromagnetic interference, freedom from sparking electrostatic discharge, low weight, and flexible harness. The European Space Agency (ESA) has been investigating fiber optic products for several years: the first operational space flight demonstrations are under development.

the potential for the introduction and development of fiber optic systems is characteristics of diverse spacecraft operations: in satellites, launchers, atmospheric entry vehicles, in ground testing of space structures, solar sails, and on board the international space stations.

Nowadays fiber optic systems based on different fiber optic products have reached a level of maturity and reliability so they can be seriously considered for spacecraft applications. Currently, fbg sensor systems have been successfully used in several acoustic and vibro-acoustic qualification tests. The performance of the fbg sensor systems has equaled or exceeded that of traditional sensors. The most significant advantages are:

  • The immunity to electromagnetic interference;Fiber Optic Products for Spacecraft Applications
  • The ability to multiplex a large number of fbg strain sensors along an optical fiber and individually interrogate them through a simple fiber;
  • The unmatched capability for making absolute strain measurements without constant monitoring;
  • Low weight;
  • Small size.

Optromix, Inc. is a U.S. manufacturer of innovative fiber optic products for 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

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ЕлизаветаFiber Optic Products for Spacecraft Applications

Single Frequency Lasers Tutorial

on June 15, 2018

Single Frequency Lasers TutorialThe single frequency fiber laser operates on a single resonator mode so that it emits quasi-monochromatic radiation with a very small linewidth and low phase noise. In addition to this, fiber lasers of this type have the potential to have very low-intensity noise. Single frequency fiber lasers can be very sensitive to optical feedback, therefore such fiber lasers have to be carefully protected against any back-reflections, often using one or two Faraday isolators. There are five types of single frequency lasers:

  • Some low-power laser diodes, in particular, index-guided types, usually emit on a single mode. The stable single-mode operation is often achieved with DFB (Distributed Feedback) lasers or DBR (Distributed Bragg Reflector) lasers;
  • Special kinds of fiber lasers allow for single frequency operation. Some of these are based on unidirectional ring laser designs, others have linear resonators and very short (highly doped) fibers. In any case, at least one fiber Bragg grating is usually used;
  • Diode-pumped solid-state bulk lasers can be forced to operate on a single mode. Output powers can reach the multi-watt level, and the linewidth can be low as a few kilohertz;
  • Vertical cavity surface-emitting lasers have very short monolithic laser resonators, thus huge cavity mode spacings, and easily emit a few milliwatts on a single mode.
  • A helium-neon laser can easily emit a single frequency if its laser resonator is made short enough (of the order of 20 cm) because the gain bandwidth is small.

Optromix develops and manufactures a broad variety of fiber lasers, СО2 lasers, ti: sapphire lasers, dye lasers, and excimer lasers. We offer simple erbium laser and ytterbium laser products, as well as sophisticated laser systems with unique characteristics, based on the client’s inquiry. Our femtosecond fiber lasers and picosecond fiber lasers offer a vast range of applications and can be used in different research fields.

If you are interested in Optromix single frequency fiber lasers, please contact us at info@optromix.com

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ЕлизаветаSingle Frequency Lasers Tutorial

Distributed feedback lasers provide a number of advantages and the largest variety of wavelengths available on the market

on June 1, 2018

Distributed feedback (DFB) lasers are considered promising light-source candidates for coherent optical transmissions over a long-distance. Dfb lasers are lasers where the whole resonator consists of periodic structure, which acts as a distributed reflector in the wavelength range of laser action and contains a gain medium. Typically, the periodic structure is made with a phase shift in its middle. This structure is essentially the direct concatenation of two fiber Bragg gratings with optical gain within the gratings. Due to the large free spectral range, wavelength tuning without mode hops may be possible over a range of several nanometers. However, the tuning range may not be as large as for a distributed Bragg reflector laser. Most dfb lasers are either fiber lasers or semiconductor lasers, operating on a single resonator mode. In the case of a fiber laser, the distributed reflection occurs in a fiber Bragg grating, typically with a length of a few millimeters or centimeters. Such dfb lasers are very simple and compact. Their compactness and robustness also lead to a low intensity and phase noise level. Semiconductor dfb lasers can be built with an integrated grating structure. Such dfb lasers are available for emission in different spectral regions at least in the range from 0,8 μm to 2,8 μm. Typical output powers are some tens of milliwatts.

Dfb lasers are characterized by temperature stability of the oscillation frequency, which is uniquely determined by the optical lattice period. The temperature dependence coefficient of the emission wavelength in a typical dfb laser is 0,1 nm/deg; it is determined by the temperature dependence of the refractive index. Such simplicity of design is a very significant advantage of tunable dfb lasers. However, the biggest disadvantage of dfb lasers is the limited frequency tuning range.

If you wish to send lots of different wavelengths down the same optical fiber in a wavelength-division multiplexed system, then any stray wavelengths can cause problems by interfering with other signals. What you therefore need is a laser that will emit almost entirely at one wavelength, you need a dfb laser. Dfb lasers are naturally more expensive due to the extra complexity of this grating being added to the semiconductor lasers. In fact, the dfb laser may be up to 1000 times more expensive than a basic Fabry-Perot laser. However, in modern optical networks, the improved performance makes dfb lasers well worth the extra money.

Optromix Inc., headquartered in Cambridge, MA, USA, is a manufacturer of laser technologies, optical fiber sensors, and optical monitoring systems.

We develop and manufacture a broad variety of fiber lasers, СО 2 lasers, Ti: Sapphire lasers, dye lasers, and excimer lasers. We offer simple erbium laser and ytterbium laser products, as well as sophisticated laser systems with unique characteristics, based on the client’s inquiry.

We manufacture lasers using our own technologies based on the advanced research work and patents of internatioDistributed feedback lasers provide a number of advantages and the largest variety of wavelengths available on the marketnal R&D team. Laser processes are high quality, high precision, easily-automated manufacturing solutions that provide repeatability and flexibility.

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

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ЕлизаветаDistributed feedback lasers provide a number of advantages and the largest variety of wavelengths available on the market

Distributed temperature sensor: analysis and forecast to 2025

on May 24, 2018

Optic sensing becomes one of the noticeable aspects, across multiple business sectors such as civil&energy, medical, automotive, aerospace, and manufacturing divisions. The worldwide distributed temperature sensing (DTS) market is majority driven by the growing optics technology-based installation. Based on applications, the market has been segmented into temperature sensing, acoustic/vibration 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.

Distributed temperature sensing systems are the optoelectronic device which measures temperatures by means of optical fiber operating as linear sensors. Temperatures are documented along optical sensor cable, not at points, but as a continuous profile. The significant accuracy of temperature determination is obtained over immense distances. Measurement distances which are more than 30 km can be monitored and some of the specialized systems can also provide even higher spatial resolutions.

The most important challenge ahead for DTS manufacturers is the high cost of DTS systems, but the key to success is providing the best value solution to customers that justifies the relative by the higher price of these systems. DTS manufacturers have the need to innovate and adapt to the shifting business requirements to keep up with the rising competition. DTS manufacturers operate in a competitive environment and there is a constant need for innovations due to the rapid technological changes. The success of DTS manufacturers is also dependent on various factors such as the commercialization of equipment, services, and other products.

Distributed temperature sensor: analysis and forecast to 2025Distributed temperature sensing systems provide the ideal solution for such applications as temperature measurement, downhole reservoir monitoring, and well completion in the oil&gas industry. These systems are indispensable in the conditions when it is necessary to operate at high temperatures or under the conditions of electromagnetic interference. Conventional temperature measurement systems are inconvenient to use in harsh operating environments. Also, it should be noted, DTS systems provide a cost-effective solution for using in oil&gas production, because in such systems, a single optical fiber acts as a sensor, replacing the need of multiple point sensors. In addition to this undeniable advantage, DTS systems have a high spatial resolution and long range, making them extremely useful in the conditions wherein it is difficult to trace the exact sensor location after preliminary engineering. Distributed temperature sensing systems are widely applied in power cable monitoring, fire detection, and pipeline leakage detection.

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 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.

If you are interested in Optromix Distributed temperature sensing systems, please contact us at info@optromix.com

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ЕлизаветаDistributed temperature sensor: analysis and forecast to 2025

Femtosecond lasers in refractive surgery

on May 17, 2018

The femtosecond laser brings micron level accuracy, needle-free, blade-free surgery to the public and is the greatest breakthrough in cataract surgery in the last 25 years. This conclusion is justified by the fact that femtosecond lasers have the potential to carry out lens extraction or cataract surgery through a pin-prick incision and is far safer and superior to current cataract surgical techniques. Combined with computer controlled optical delivery systems, femtosecond lasers can produce precise surgical incisions without collateral damage to surrounding tissues. Several femtosecond laser systems have been introduced clinically and more two million ophthalmic procedures have been performed with femtosecond lasers, primarily for the creation of a corneal flap in LASIK. The precision of femtosecond lasers exceeds that of highly sophisticated mechanical devices, with fewer likely collateral tissue effects.

The femtosecond laser is an infrared laser (wavelength: 1,053 nm) with an ultrashort pulse duration (10-15 s). The early femtosecond laser systems operated with a low repetition rate (15 kHz) and thus required higher energy to operate. The new devices have an increased repetition rate (as high as 150 kHz), which leads to utilization of less energy and shorter procedure duration. Also, the new devices vary in their programmed and customizable geometric cut patterns. Each laser system has distinctive features allowing it to be popularized for use in specific procedures.

Femtosecond lasers in refractive surgeryThe femtosecond laser has the ability to deliver laser energy with minimal collateral damage to the adjacent tissue due to the fact that its short pulse duration. The tissue interaction femtosecond lasers utilize is known as photo-disruption, a process in which small volumes of tissue are vaporized resulting in the formation of cavitation gas (carbon dioxide and water) bubbles. In addition to this, the femtosecond laser is unique in that it can be focused anywhere within or behind the cornea and is capable, to a certain extent, of passing through optically hazy media such as an edematous cornea. The laser may be applied in multiple geometric patterns including vertical, spiral, and zigzag cuts.

Studies show that femtosecond laser applications in liquefaction, capsulorhexis, and corneal incisions are safe and effective. Laser system optimization will further improve the effectiveness of liquefying dense cataract. There are several high-tech features that bring femtosecond lasers to a new level of precision:

  • real-time video imaging, which provides three-dimensional visualization of the eye during the procedure
  • curved patient interface
  • an intuitive touch screen graphic user interface, which allows tracing each step of the procedure to be easily planned, customized and executed
  • hue image-guided surgical planning.

Femtosecond lasers generate ultrashort pulses that utilize small amounts of energy and minimize damage to any of the surrounding tissues. Femtosecond lasers can be used in multiple avenues of anterior segment surgery thanks to the versatility, predictability, and unique properties. Despite the successful and widespread use of the femtosecond laser in ophthalmic surgery, for many ophthalmologists and patient around the world, access to these costly lasers is a challenging limitation. A further logistical problem can take place if the laser system and operating room are not in close proximity. It is anticipated that this technology may become more accessible over time with increased surgical efficiency and improved patient outcomes.

New fields in refractive surgery can be opened and others can be expanded, as a refractive lens exchange where its indications may be greatly increased, considering the new safety and precision standards that the technology can deliver. The expectations are huge and future studies will show how far we can go with the technology.

Optromix Inc., headquartered in Cambridge, MA, USA, manufacture lasers, optical fiber sensors, and optical monitoring systems. We develop and manufacture a broad variety of fiber lasers, femtosecond fiber lasers, СО 2 lasers, Ti: Sapphire lasers, dye lasers, and Excimer Lasers. We offer simple erbium laser and ytterbium fiber laser products, as well as sophisticated laser systems with unique characteristics, based on the client’s inquiry.

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

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ЕлизаветаFemtosecond lasers in refractive surgery

Optical Sensors for the Exploration of Oil and Gas

on May 4, 2018

The technology and markets for the fiber optic solutions are very broad. The growth of Distributed Temperature Sensing (DTS) market is driven by the rising demand for DTS systems for monitoring process in hostile working conditions. The demand for the DTS systems is growing due to the fact that such systems can be deployed over long distances and increasing need for improved safety systems. The Oil and Gas applications are expected to hold the largest size of the DTS market during the forecast period because the DTS technology has become an integral part of the Oil and Gas industry. DTS systems help in continuous real-time downhole monitoring to optimize the operational and economic performances of the assets. These possibilities enable the reservoir engineers to gain a better understanding of the injection and production dynamics and accordingly optimize the production and improve recovery leading to improved profits. There is an increasing focus on adopting the technology for improving the productivity of brownfield operations. The analysis of the data collected by the DTS systems can provide additional information of the behavior of the wells such as the flow volume within a particular section of the wells.

Optical Sensors for the Exploration of Oil and GasMany land and underwater oil operations for improved safety and functionality in harsh environments depend to a large extent on Distributed Temperature Sensing (DTS), Fiber optic solutions ensure sustainable performance and durability in high-temperature, high-pressure, and hydrogen-rich environments. The temperature is a scalar quantity. This parameter can be measured in a borehole without great efforts. However, the interpretation of downhole temperature measurements is often complex and needs an integrative approach. Distributed Temperature Sensing systems are based on optical time-domain reflectometry and meanwhile an innovative and canonical technology for the registration of temperature field and its temporal and spatial distribution along a fiber optic cable. DTS manufacturers develop DTS market which has advanced rapidly over the last few years on the Oil and Gas industry. Studies in this field and their various interpretations are demonstrating the versatile possibilities for DTS, and further developments for the use of fiber optic equipment in the Oil and Gas industry are discussed. The use fiber optic equipment is not limited to temperature measurements, also acoustic vibrations can be detected and used for seismic measurements (Distributed Acoustic Sensing (DAS)).

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 monitoring of various facilities all over the world.

We provide a distributed acoustic sensing system that is much less expensive than other analogous systems present on the market. If you are interested in Optromix distributed acoustic sensing system, please contact us at info@optromix.com

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ЕлизаветаOptical Sensors for the Exploration of Oil and Gas

The “Raman Effect” and Its Applications

on April 24, 2018

High-power fiber lasers have seen tremendous development in the last few years. Currently, the Raman fiber lasers among other fiber laser systems are the only known wavelength-agile, scalable, high-power fiber laser technology that can span the wavelength spectrum. Pulse pumping is an efficient way to generate the Raman fiber laser. Nonetheless, it should be considered that it requires real-time synchronization between the pump pulses and the laser cavity. Raman fiber lasers are fueled simultaneously by industrial and defense applications. The accelerating pace of progress in the field of such laser systems is occurred with rare-earth-doped fiber lasers, in particular through ytterbium-doped fiber lasers.

In the last few years, there has been an increasing interest in Raman laser technology. The Raman fiber lasers have the potential to extend the spectral coverage of standard solid-state and semiconductor lasers and allow for multi-wavelength operation via non-linear conversion using a single compact device. Nowadays the commercially available Raman fiber lasers can deliver output powers in the range of a few tens of Watts in continuous wave(CW) operation.The “Raman Effect” and Its Applications

The Raman fiber lasers are specific fiber lasers in which fundamental light-amplification mechanism is stimulated Raman scattering. Such “inelastic scattering of light”, or “Raman effect”, was observed in practice for the first time in 1928 by C.V. Raman. This scientist was awarded the Nobel Prize in 1930 for this invention. Raman spectroscopy is a frequency in the studied material or substance shifted by this “Raman effect”. Such spectroscopy is one of the vibrational spectroscopic technique used to provide information on molecular vibrations and crystal structures. This method uses a fiber laser light source to irradiate a sample and generates an infinitesimal amount of Raman scattered light. Raman spectroscopy is a useful technique for the identification of a wide range of substances: solids, liquids, and gases. It is straightforward and non-destructive technique. The aforementioned type of spectroscopy involves illuminating a sample with monochromatic light and using a spectrometer to examine light scattered by the sample.

Optromix provides world-class laser systems and it is our highest priority to deliver the best quality products to our clients. Our main specialization is manufacturing single frequency fiber lasers. When manufacturing our single frequency fiber laser products we implement unparalleled quality management system with world-class requirements and regulations. Optromix erbium laser, ytterbium laser, СО2 laser, Excimer laser, and Ti: Sapphire laser technologies offer a vast range of applications and can be used in different research fields. We prioritize the needs of our clients and we are always dedicated to creating unique and innovative technologies.
If you are interested in Optromix fiber laser systems for laser cutting, please contact us at info@optromix.com

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ЕлизаветаThe “Raman Effect” and Its Applications

Distributed Acoustic Sensing for Seismic Monitoring and Exploration

on April 19, 2018

Distributed Acoustic Sensing (DAS) system is a recent technology using fiber-optic cables to detect acoustic disturbances such as seismic signals and a flow noise. This promising technology has already been successfully applied in hydraulic fracture monitoring and for needs of Vertical Seismic Profiling (VSP).

How is this monitoring carried out? A laser pulse is launched into the optical fiber in order to measure the dynamic strain changes along the whole length of the fiber. An optical signal is backscattered from every position along the fiber through elastic Rayleigh scattering. As a result of applying a coherent laser source, the backscattered photons from different positions within the optical fiber interfere with each other. The phase of the backscattered signal begins with a change in the relative position of the scattering molecules, which in turn change the resulting interference pattern at the receiver.

The foundation that supports our modern infrastructure is the top tens of meters of the Earth’s surface. The near-surface changes can lead to the emergence of hazardous conditions in adjacent territories. For instance, the thaw of permafrost presents a serious threat to the buildings and installations because it causes ground subsidence. Also, the dissolution of subsurfaces can provoke local crises like the emergence of devastating sinkholes. The seismic monitoring systems have the potential to provide early warning of near-surface hazards. The ability to detect hidden dangers in time is especially important because many of them in the early stages are manifested only as time-lapse in the velocities of the seismic waves.

Distributed Acoustic Sensing for Seismic Monitoring and ExplorationSeismic methods using fiber-optic Distributed Acoustic sensors are a cornerstone for the exploration of the surface. The downhole measurements help to gather the full information, which will be useful to understand the rock properties and the potential fluid pathways within geothermal reservoirs. Temperatures within geothermal wells, it should be noted, often exceed the temperature limitation of conventional seismic sensors. This difficulty can be overcome by the application DAS technology. Special optical fibers can be operated at the temperature up to 100 degrees centigrade. The optical fiber has to be lowered into the well for DAS measurements. These seismic measurements can be performed along the entire length of the optical fiber simultaneously. The temperature limitation of the measurement set-up is defined by the temperature rating of the fiber optic cable as all the electronics are operated from the surface.

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 Acoustic Sensing systems (DAS). 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 monitoring of various facilities all over the world. The use of Distributed Acoustic Sensing technology in downhole applications (all using the same optical fiber cable) gives a continuum of benefits that are distributed to the flow profiling and the condition monitoring. Distributed acoustic sensing systems can be retrofitted to existing installations of permanent in-well fiber optics based monitoring systems with the addition of surface equipment. New installations of DAS systems are also possible and have already been performed.

If you are interested in DAS systems and want to learn more, please contact us at info@optromix.com

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ЕлизаветаDistributed Acoustic Sensing for Seismic Monitoring and Exploration

Distributed Acoustic Sensing (DAS): Theory and Applications

on April 13, 2018

Introduction

Distributed Acoustic Sensing is a recently developed passive fiber-optic sensing technology based on the interaction of two components: optical fiber and the speed of light. The combination of these two components creates a mechanism insulated from environmental interference. The ability of optical fiber to detect acoustic signal anywhere along the length of the fiber with a high frequency response and a tight spatial resolution has a particular appeal for functions involving remote an hard-to-reach areas. The DAS technology is highly attractive because it is fully self-contained: the light source is never exposed to anything but the medium being measured. Fiber-optic Distributed Acoustic Sensing accordingly takes advantage of the fact that the reflection characteristics of the laser light depend on only factors which affect the optical fiber itself such as temperature, strain or sound. A DAS system converts a standard optical fiber into an array of acoustic sensors. Each of these sensors is able to determine the time-varying strain at any position along the optical fiber’s length. Distributed Acoustic Sensing technologies are superior to more traditional acoustic systems: such obsolete systems aren’t able to respond to fast and small amplitude variations in the strain. In addition to this, DAS systems can operate in a fully continuous manner over many kilometers of optical fiber in contradistinction to traditional methods.

Distributed Acoustic Sensing (DAS):  pipelineHow does Distributed Acoustic Sensing work?

DAS systems work by injecting a pulse of the laser light into the optical fiber. This pulse of the light travels down the optical path, creating interactions within the fiber. These interactions, in turn, lead to the emergence of reflections known as a “backscatter”. The backscattered light moves the fiber back toward the Distributed Acoustic Sensor where it is sampled. For each pulse of the laser light, routinely at every 1 metre, the distance of the entire fiber is sampled at each point along the length of the fiber. The result of all these interactions is a continuous acoustic sampling without cross talk and with frequency range from millihertz to over 100 kHz and with a dynamic range of over 120dB.

Applications

Nowadays fiber-optic Distributed Acoustic Sensing systems find a wide variety of applications as monitoring tools in process vessels, storage tanks and piping systems. It is possible to schedule maintenance programs and maximize service life of equipment with their help.

Pipelines: DAS technology provides a timely warning for activities such as digging and drilling operations. It is also perfect for leak detection of existing underground pipelines. The applications of DAS systems for leak detection have been successfully demonstrated to provide non-intrusive digital pipeline monitoring: DAS acts like an early warning system that allows operators to act quickly in case of a pipeline leakage or intrusion into a plant area or a leakage into the environment.

Railways: When applied to the railway industry, Distributed Acoustic Sensing systems deliver a comprehensive rail monitoring solutions to operators and system integrators. Such technologies enable train tracking, asset condition monitoring and various applications for security requirements.Distributed Acoustic Sensing (DAS):  railways

Oil, Gas Industry: DAS systems looks poised to add value to fiber-optic sensor monitoring solutions for different wells and reservoirs. Distributed Acoustic Sensing technologies in this industry help to facilitate to the end of existing fiber optics already deployed in the well and allow acoustic data to be away and then transfer to the cloud for analysis.

Seismic monitoring: Distributed Acoustic Sensing systems is a promising development in the use of fiber-optic cable for measurement of ground motion. Discrete fiber-optic sensors which use a Bragg diffraction grating have been in research and development and field testing for more than 15 years with geophysical applications for at least 12 years.

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 Acoustic Sensing systems (DAS). 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 monitoring of various facilities all over the world.

If you are interested in DAS systems and want to learn more, please contact us at info@optromix.com

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ЕлизаветаDistributed Acoustic Sensing (DAS): Theory and Applications