High-power ultrafast fiber lasers offer new applications

ultrafast fiber lasers

Benefits of ultrafast fiber lasers

Ultrafast fiber laser systems provide two unique benefits that include the highest accuracy in material processing and the capability to process almost every material. Fiber lasers of average powers, up to approximately 100 W, are used for industrial applications, while laser systems of higher powers are more suitable for research.

Development of next-generation fiber lasers

Also, the popularity of fiber laser systems is growing. A team of researchers from Germany has developed the next generation of ultrafast laser systems with enough power to overcome standard lasers. Apart from the development of fiber lasers, it is planned to create process laser technology and the first applications as well.

Laser design and efficiency

The team consists of laser beam source development groups that work on complementary approaches to create a totally new fiber laser system. The new fiber laser is based on a decade-long experience with a special slab laser system design. The fiber laser is perfect for the generation of continuous-wave (CW) laser beam radiation efficiently with diode pumping.

High-power pulsed radiation

This laser system is considered to be a solution for the emission of pulsed and ultrashort-pulsed laser beam radiation. The present version is developed for 5 kW laser beam radiation with 800 fs pulses from two amplifier stages. The power radiation is planned to increase up to 10 kW by using a thin disk amplifier stage.

Coherent beam combination concept

The concept of a coherent combination of fiber laser beams has also been developed. According to the concept, “almost-identical fiber amplifiers are pumped by one seed laser system, and they then generate amplified laser beams in parallel. With optimal spatial and temporal overlap, these beams can be combined with 96% combining efficiency.” The fiber laser has already been tested and demonstrated 10.4 kW of compressed average power with 240 fs pulses.

Process technology for applications

Additionally, the researchers pay attention to process technology to promote the efficient application of such high powers, resulting in the development of high-speed polygon scanners that improve laser beam deflecting and splitting schemes. The process of splitting off a multikilowatt laser beam into arrays of more than 100 identical but shaped laser beamlets allows performing high-throughput micromachining.

Recent progress in fiber lasers: challenges and perspectives

rogue waves in fiber lasers

Rogue waves in fiber lasers

Rogue waves are considered to be rare, extreme amplitude, localized wave packets, which are the subject of great interest now in various areas of physics. Fiber laser systems provide abundant nonlinear dynamics that are perfect for an examination of optical RW formation. Fiber lasers have made great research progress on rogue waves.

Fiber lasers as nonlinear optical systems

Fiber laser systems act as a dissipative nonlinear optical system, and they are widely used for the study of optical solitons. Ultrafast fiber lasers allow examining soliton interactions, molecules, rains, noise-like pulses, and soliton explosions, which are closely linked to the RW generation.

Dissipative rogue waves

These laser systems offer a proper platform for the production of dissipative RWs. It is possible to measure the dynamics of RWs within each round trip in a fiber laser. These waves in fiber laser systems are not new and have already been tested; the study of dissipative RWs in laser systems continues to develop quickly.

Classification of rogue waves

Rogue waves in fiber lasers are possible to be categorized by laser beam duration: slow, fast, and ultrafast RWs. Various mechanisms take part in their generation. The measurement of ultrafast RWs is highly challenging when applying the standard technique. Also, types of dissipative RWs emitted by fiber laser systems include RWs created by chaotic structures, dark three-sister RWs, and the laser beam pulse waves produced as a result of the multiple-pulse interaction.

Vortex laser beams and applications

Fiber lasers enable the generation of vortex laser beams that offer promising applications in quantum optics, optical micromanipulation, rotation detection, WDM (mode-division multiplexing) systems, and nonlinear fiber optics. These laser beams find applications in modulating elements, containing the mode-selective couplers, long-period fiber gratings, and microstructured fiber facets. There are the mode-locked vortex beams, which is why the optical RWs based on the vortex laser beams in the fiber laser systems remain popular research topics, favoring the further development of nonlinear optics.

Temporal cavity solitons in fiber lasers

Laser systems without the mode locker installed in the cavity allow emitting ultrashort laser beam pulses, for instance, the temporal cavity solitons. “When the dispersion and nonlinearity are balanced in the fiber lasers, TCSs are formed, which can transmit indefinitely and keep their shape in the fiber cavity”. Thus, fiber laser systems are perfect for observation of the generation of optical RWs as well as to investigate their behavior because rogue waves present a threat to the safety of seagoing personnel and ships.

New versatile fiber laser cuts metal tubes

fiber laser tube cutting machine

New fiber laser tube cutting machine from Germany

A manufacturer of cutting machines based on fiber lasers from Germany has developed a laser system tube cutting machine. The company claims that the fiber laser system is considered to be “a cost-effective choice even at low to medium capacity utilization, suitable for companies that are entering this sector and those seeking to expand production capacity.”

Applications and processing capabilities

The fiber laser cutting machine provides the versatile processing of tubes and profiles; this fiber laser technology can replace standard tube processing steps like sawing, drilling, and milling. The applications of new laser systems include profiles, round tubes, and flat steel bars. Moreover, it allows processing L and U profiles. The 2 kW solid-state fiber laser provides high-speed cutting of mild steel, stainless steel, aluminum, and nonferrous metals, for instance, copper and brass.

Technical specifications and automation

The fiber laser system enables cutting tubes with diameters of up to 152 millimeters and profiles with an outer circumference of up to 170 millimeters. The laser technology used in the new cutting machine performs automatic adaptation to the tube dimensions without the necessity of manual adjustment. The fiber laser also sets up other crucial settings automatically. It is enough to touch only one button on the laser system to provide the reliable cutting of lower-quality materials.

Performance and production benefits

Fiber laser cutting machine enables cutting tubes weighing up to 18.5 kg/m with material thicknesses of up to 8mm. Also, the automated loading system makes the laser system machine a cost-effective solution for high-volume production. There is an opportunity for users to make changes to the fiber laser system’s production schedule or control it through an app, making the process easier.

About fiber lasers

fiber laser systems

Rapid growth of fiber laser systems

In the laser system world, few devices seem to have gained popularity among users as quickly as early fiber laser systems. Fiber lasers are considered to be a significant breakthrough compared to opportunities provided by earlier laser technologies, such as the first pumped diode systems, or established methodologies, for instance, the CO2 laser system.

What makes up a fiber laser system

For engineers and scientists, a fiber laser system is a device in which “an active amplification medium is an optical fiber doped with rare-earth elements such as erbium, ytterbium, neodymium, dysprosium, praseodymium, thulium, and holmium”.

CO2 lasers compared to fiber lasers

CO2 laser is a laser system that uses carbon dioxide, a colorless gas with a density of about 60 percent higher than that of dry air. It allows the use of an infrared laser beam with wavelength bands centered at 9.4 and 10.6 micrometers. This laser beam level is suitable for cutting a wide variety of materials. CO2 laser systems are also useful in medical applications such as soft tissue surgery or dermatology.

How fiber lasers differ

In contrast, the fiber laser replaces the gas with a conventional optical fiber made of quartz glass. This fiber is then “doped” when a little bit of one of the rare earth elements is added to it. The atoms that make up the laser beam medium are then placed in this rare-earth-doped fiber. When photons are emitted, they are enclosed within this doped optical fiber core.

Key advantages of fiber lasers

Stability

The idea of limiting photons in a rare-earth-doped fiber gives fiber laser systems a major advantage over their competitors: stability. Since the fiber laser generates its beam inside the core, it does not require sophisticated or sensitive optical equipment to deliver the laser beam.
On the other hand, a conventional laser system uses an optical fiber to move the laser beam or a mirror to reflect it. Either approach works, but both require extremely precise alignment. This makes standard laser systems sensitive to movement and shock. And as soon as everything fails, the specialist must fix everything. The fiber laser does not have this sensitivity. It is stable. The fiber laser systems can handle bumps, vibrations, and general dissonance on an assembly line.

Beam quality

There is another advantage, which is that the laser beam is limited by a core of doped optical fiber: it keeps the beam straight and small. This, in turn, allows for reducing the need for focusing. As a rule, in laser systems, the smaller the point created by the laser beam, the more efficient the cutting is.

Energy efficiency

Another advantage is that fiber lasers are energy efficient. The fiber laser systems can convert almost 100 percent of the input signal they receive into the laser beam, thereby limiting the amount of energy converted to thermal energy. This means that the optical fiber tends to remain protected from heat damage or destruction. All this creates a reliable laser system that requires almost no maintenance.

High-powered fiber laser systems

fiber laser

What is a fiber laser?

A fiber-optic or fiber laser is a laser system where the active amplification medium is represented by an optical fiber. It is doped with rare-earth elements such as erbium, ytterbium, neodymium, dysprosium, praseodymium, thulium, and holmium. They are related to doped fiber optic amplifiers, which provide laser beam light amplification without generation.

Nonlinear effects in fiber lasers

Fiber nonlinearities in laser systems, such as stimulated Raman scattering or four-wave mixing, can also provide amplification and thus serve as an amplifying medium for the fiber laser.

Distinctive features of fiber laser systems

The distinctive advantages of fiber laser systems over other types of lasers are the following: laser beam light is generated and delivered using an inherently flexible medium, which makes it easier to deliver it to the focus point and target.

Industrial advantages

This can be important for laser system cutting, welding, and joining metals and polymers. Another advantage is the high-power laser beam output.

Efficient cooling and compact design

Fiber lasers can have active regions several kilometers long and can provide very high optical gain. These laser systems can maintain kilowatt levels of continuous output power due to the high fiber optic surface-area-to-volume ratio, which provides efficient cooling.
The waveguide properties of the fiber reduce or eliminate thermal distortion of the optical path, usually creating a diffraction-limited, high-quality laser beam. Fiber lasers are compact compared to solid-state or gas laser systems of comparable laser beam power since the fiber can be bent and coiled, except for thicker rod structures, to save space. They have a lower cost.

Performance and reliability

Fiber lasers are reliable and have high temperature and vibrational stability, as well as long service life. The peak laser beam output power and short pulses make the marking and engraving perfectly clear and readable. The ability to increase the power of the fiber laser systems and perfect laser beam quality produces smooth cutting edges with high roughness and fast cutting speed of metals.

Fiber lasers in material processing

Laser technology for processing, which was born about three decades ago, is currently experiencing the peak of its development and popularity. Modern fiber laser technology is rapidly being introduced into industrial production and the advertising business, often replacing traditional methods of material processing.

Applications in industry

The focused laser beam of adjustable power turned out to be an ideal “working tool” for the creators of new equipment. The fiber laser for cutting and marking, welding and surfacing, as a material processing tool, works quickly and does not wear out; it is economical, highly accurate, and its impact is easy to control and manage.

Principle of fiber laser processing

The principle of laser system processing is the effect of a focused laser beam on the surface of the processed product. The result of this action is a change in the structure and color of the material, its melting, and evaporation of the surface layers of the material or coatings. Fiber laser cutting, as a precision tool, enables the creation of items with reduced material use and eliminates the need for further processing of the cut edges. 

Nanotechnology enhances fiber laser’s power

holmium fiber laser

Breakthrough with holmium-infused glass fibers

Holmium-infused glass fibers open the possibility of developing high-powered fiber lasers. Scientists from the USA have presented a new technique that allows designing powerful fiber lasers that are considered to be more efficient and safer for eye surgery due to the application of nanotechnology.

Rare-earth-ion-doped fiber technology

The nanoparticles are applied to produce a “rare-earth-ion-doped fiber” that consists of silica fiber infused with ions of the rare-earth element holmium. This material offers 85% efficiency of fiber laser systems.

Operating principle

The operating principle of the laser system is based on a pump source (quite often provided by another fiber laser) that excites the rare-earth ions, which lead to photon emission to create a high-quality laser beam at the desired wavelength.

Efficiency limitations in fiber lasers

The fiber laser technology does not provide 100% efficiency.

Pump energy vs. output light

The energy applied is seen as pump energy, but this does not represent the high-quality laser beam light at the needed wavelength. A much higher quality of light in the fiber laser system is possible to obtain at the specific wavelength; the energy that isn’t converted into laser beam light is wasted and converted into heat.

Importance of efficiency

This loss of energy defines the significant limitation of power scaling and the laser system’s quality, which makes qualities such as efficiency especially important. The doping process from nanoparticles enables fiber lasers to achieve 85% efficiency with a laser system that operates at a 2-micron wavelength (safe wavelength for eye surgery compared to standard 1-micron lasers).

Safety considerations for eye surgery

Scattered light risks

“The danger arises from the risk of scattered light being reflected into the eye during a laser beam’s operation.” For instance, scattered light from a 100-kW fiber laser operating at 1 micron can result in serious damage to the retina and blindness as well.

Eye-safe wavelengths

An “eye-safe” laser system that operates at wavelengths beyond 1.4 microns greatly decreases risks from scattered light.

Role of nanotechnology in overcoming challenges

Nanotechnology allows for overcoming several other challenges.

Protection of rare-earth ions

The first is that it protects the rare earth ions from the silica in fiber lasers.

Separation of ions

“The nanoparticle doping also separates the rare-earth ions from each other, which is helpful because packing them closely together can reduce the light output.” Conventional laser systems operating at 1 micron, applying a ytterbium dopant, are more resistant to these factors.

The first tunable, chip-based vortex laser system

vortex fiber laser

Breakthrough in vortex laser technology

Researchers from the U.S have presented a micro laser system that makes it possible to dynamically tune to numerous distinct OAM modes. They confirm that the OAM modes of fiber lasers are measured by a chip-based detector. Two laser technologies have been combined in this research, resulting in the first tunable, chip-based vortex fiber laser system.

Why vortex laser systems matter

These vortex laser systems are named for the manner in which their light twists around their axis of movement.

Previous limitations

Although the laser technology is not new, it has some limits to transmitting a single, pre-set OAM mode, resulting in inefficient encoding of more information.

Detector challenges

Additionally, current detectors use complex filtering methods applying bulky components that make them impossible to integrate directly onto a chip; they are considered to be incompatible with most practical optical communications approaches.

Advancements in fiber lasers and detectors

Since fiber lasers and detectors have now become more accurate, they both allow consistently emitting and distinguishing between various amplitude levels, leading to more data to be included in the same signal.

Additional laser beam qualities

More sophisticated laser systems and detectors enable changing other qualities of laser beam light, for instance, its wavelength, which corresponds to a color, and its polarization, which is regarded as the orientation of the wave’s oscillations relative to its direction of travel.

Research from Pennsylvania

The research on a dynamically tunable fiber laser system based on this technique is presented by the researchers from Pennsylvania.

Microring laser system

According to the research, the first step was working with a “microring” laser system that includes a ring of semiconductor, only a few microns wide, through which the laser beam light circulates indefinitely as long as power is supplied.

Coupling SAM and OAM

“Asymmetry between the two control arms allows for the SAM of the resulting fiber laser to be coupled with OAM in a particular direction.”

Helical pattern of OAM modes

Instead of simply rotating around the axis of the laser beam, the wavefront of this fiber laser system orbits that axis and therefore travels in a helical pattern.

Chirality and information expansion

OAM mode of the laser system follows its chirality, the direction those helices twist, and how close together its twists are. The new fiber laser technology has already been tested and demonstrated the ability to emit five distinct OAM modes, leading to expanding the information channel of such fiber lasers by up to five times.

Fiber laser systems for material processing

fiber laser processing

Introduction to fiber laser material processing

Laser technology for material processing is currently experiencing the peak of its development and popularity. Modern fiber laser technologies are rapidly being introduced into industrial production and the advertising business, often replacing traditional methods of material processing.
The focused laser beam of adjustable power turned out to be an ideal “working tool” for the creators of new equipment. The laser system for cutting and marking, welding and surfacing, as a material processing tool, works quickly and does not wear out; it is economical, highly accurate, and its impact is easy to control and manage.

Advantages of fiber laser technologies

Laser  technologies for material processing have several advantages that contribute to the expansion of their application in various industries and services:

  • a diverse selection of processed materials.
  • no mechanical impact on the product with minimal thermal,
  • precision and guaranteed repeatability,
  • high contrast and durability of the images applied,
  • high speed and performance, saving on consumables, and low power consumption,
  • possibility of laser beam processing in hard-to-reach places, on flat and curved surfaces,
  • the ability to integrate the fiber laser into various technological processes, including production lines and robotic systems.

Applications of fiber laser systems

Laser system engraving and cutting

Laser system engraving is effective for personalization of souvenirs and gifts, and fiber laser application for personal and greeting inscriptions. Laser beam cutting as a high-precision tool allows for the production of products with minimal material consumption and without additional processing of the cutting edges.

Laser system welding

Laser system welding is characterized by high welding speeds and high-quality welds with minimal weld sizes.

Laser hardening

A fiber laser or thermal hardening of metals and alloys by laser beam emission is based on local heating of a surface area under the influence of radiation and subsequent cooling of this surface area at a supercritical rate as a result of heat transfer to the inner layers of the metal.
In contrast to the known processes of thermal hardening by quenching with high-frequency currents, electric heating, melt quenching, and other methods, heating during laser beam hardening is not volumetric, but a surface process. At the same time, the heating time and cooling time are insignificant, and there is almost no exposure at the heating temperature. 
These conditions provide high rates of heating and cooling of the treated surface areas. Due to these features, the formation of the structure during laser beam heat treatment has its own specific features. The main purpose of fiber laser thermal hardening of steels, cast iron, and non-ferrous alloys is to increase the wear resistance of parts working under friction conditions. 
As a result of laser system hardening, high surface hardness, high dispersion of the structure, a decrease in the coefficient of friction, an increase in the bearing capacity of the surface layers, and other parameters are achieved. Fiber laser hardening provides the lowest wear and friction coefficient, and furnace quenching – the highest. 
Along with this, hardening by the fiber laser system is characterized by very small running time (only two or three cycles), a decrease in the upper values of the number of acoustic emission pulses, and a small interval of change in the number of laser beam pulses. This is due to an increase in the uniformity of the microstructure of the surface area after laser system hardening.
The wear resistance of cast iron and aluminum alloys under sliding friction conditions after continuous laser treatment is noticeably increased. The increased wear resistance of cast iron after laser beam treatment is due not only to the corresponding structural and phase composition but also to improved friction conditions. It also increases the wear resistance of steels and some other alloys when friction occurs in alkaline and acidic environments.

Laser system cutting

Fiber laser cutting is a laser technology that uses the energy of a laser beam to cut various materials. Laser cutting is usually used on industrial production lines. Technologically, this process is reduced to focusing a high-energy laser stream on the material being cut. The material, in turn, begins to melt, burn, evaporate, or be removed by a stream of auxiliary gas. 
The laser beam cut is characterized by high edge quality and positioning accuracy. Powerful industrial fiber lasers can cut metal sheets and other materials of various shapes with equal ease. Laser system cutting has a number of advantages over other metal-cutting methods. 
The advanced equipment of the fiber laser system cutting machine is able to process almost all metals and their alloys. It becomes possible to achieve a minimum area of the cut, while there is almost no deformation of the edges. The purchase of laser system cutting equipment is advisable in cases where it is necessary to perform the following types of work:

  • Machine processing of metal without high initial costs and physical contact with the metal
  • Metal processing without using a large amount of manual labor
  • Metal cutting that does not involve further processing of the part
  • High-speed metal cutting, which is accompanied by a slight thermal effect on the metal surface
  • Cutting of finished products (past painting processes, etc.) without losing the external qualities of the part.

The fiber laser is able to operate in pulse-periodic and continuous modes. The technological capabilities of the laser beam equipment allow performing metal cutting operations that are accompanied by a small amount of waste. Since the laser system cutting machine is characterized by high positioning accuracy, it is possible to significantly reduce the cut tolerance, which leads to high economic efficiency of cutting. 
The laser beam of high quality makes it possible not only to cut metal with high precision but also to create holes in it with a diameter of 0.2 mm or more. The fiber laser system for cutting is characterized by a high speed of operation, which depends on the power of the laser beam.
Laser cutting equipment makes it possible to process non-rigid parts and parts that are easily subject to deformation. The use of laser technology enables cutting out details of any, even the most complex contour.

Laser engraving

Fiber laser engraving includes the removal of the surface layer of a material (metal, plastic, leather) or coating (paint, electroplating, spraying) under the influence of the laser beam of high quality. Laser system engraving will not be erased and will not fade. It can rightfully be called eternal. 
The laser beam process is controlled by a computer, which allows engraving images from any digital format (after the necessary processing). The laser beam of high quality allows applying high-resolution images. This makes it possible to engrave high-quality microimages and microtexts.
The laser beam modes embedded in the system can vary widely. This allows adjusting the depth of the burning of the material. For example, there is a deep engraving in metal for maximum clarity and durability, or evaporation of the top layer of paint for the product label without affecting the material itself.
In addition to the standard three-dimensional laser system engraving, there is a technology for obtaining color engraving. Colors in fiber laser engraving of metal are achieved due to the appearance of oxide films in the area of laser beam exposure. The laser technology for obtaining them is innovative and unique. The colors are selected separately for each new material.

Laser welding

Fiber laser welding is a welding technology used to attach various parts of metal using a laser system. Due to the high concentration of laser beam energy in the welding process, a small volume of molten metal, the small size of the heating spot, high rates of heating and cooling of the weld metal, and the near-weld zone are provided.
The process is often used to perform large volumes of production, such as in the automotive industry. Depending on the purpose, continuous or pulsed fiber laser operation can be used. A laser beam with a pulse time of the order of milliseconds is used for welding very thin workpieces. A continuous laser system is used for deep welding.
Fiber laser welding is a universal welding method that can be used to weld carbon steel, stainless steel, aluminum, and titanium. A high cooling rate can lead to thermal damage when welding carbon steels. The welding quality is high, similar to electron beam welding. The welding speed is proportional to the applied power and also depends on the type and thickness of the workpieces. 
The high power potential of fiber laser systems makes them particularly suitable for large production volumes. This type of welding is particularly dominant in the automated industry. Some of the advantages of fiber laser welding compared to conventional include: air route can be used to transmit the laser beam, that is, there is no need to vacuum, it is easy to synchronize manipulators, there is no X-ray radiation, and it provides the best quality of welds.
One of the methods of laser system welding is hybrid laser beam welding. This is a combination of laser and arc welding (gas metal arc welding). The electric arc melts the wire, ensuring a constant arc length, while the wire is fed automatically by the wire feeder. Protective gases (argon, helium, carbon dioxide, and their mixtures) are used to protect against the atmosphere that appears from the welding head, together with the electrode wire.

Soliton fiber laser systems overcome constraints

ultrashort laser pulses

Ultrashort laser pulses and their challenges

The generation of ultrashort laser beam pulses needs careful monitoring of the light’s dispersion provided by a fiber laser. There is a dependency of phase velocity and frequency; a real laser beam pulse includes a spread in frequency, which will enlarge as it goes through an optical medium. Thus, simple, low-cost sources of sub-picosecond laser beam pulses, soliton fiber laser systems, including a laser diode and an optical fiber, are considered to become an ideal solution.

Balancing dispersion with Kerr focusing

This type of laser system allows decreasing the spread by “balancing it against Kerr focusing – the narrowing of a laser beam pulse caused when light’s electric field alters the medium’s refractive index – so each pulse travels as a soliton, and its duration remains unchanged.”

Limitations of traditional soliton fiber lasers

Soliton fiber lasers are regarded as very promising because of such benefits as simple construction; they are not able to reach the high energies of techniques, for instance, chirped-pulse amplification.

Overcoming energy constraints with new technology

New fiber laser technology allows overcoming these limitations. The operating principle of the fiber laser is based on the application of a spatial light modulator to manage the light’s dispersion relation to enabling higher laser beam energy pulses. A dispersion relation demonstrates how a wave’s frequency is relevant to its wavelength. “For light in a conventional soliton laser, the function is approximately quadratic, and its second derivative describes how a laser beam pulse would spread in the absence of Kerr focusing.”

Role of higher-order dispersion

Researchers from Australia have demonstrated that higher-order dispersion provides real benefits. A photonic crystal waveguide based on fiber laser technology has been developed, where the effects of second- and third-order dispersion were suppressed due to the waveguide’s geometry. The balancing process of fourth-order dispersion with Kerr focusing is connected to soliton formation.

Programmable spatial light modulators

The soliton fiber laser system acts by applying the same principle. The researchers employed a programmable spatial light modulator instead of a specially designed waveguide to produce the required dispersion profile. Additionally, the researchers claim that the energy of the quartic laser beam pulses is regarded as proportional to τ−3, as predicted for fourth-order dispersion solitons.

Fiber laser systems analyze cells non-destructively

fiber laser microscopy

Modern laser systems in microscopy

Modern laser systems in microscopy allow researchers to discover how molecules within a cell react and interact when it comes to investigating tumor growth. Laser beam microscopy requires to be labeled with fluorescent substances that make them visible to researchers; however, it may misrepresent the molecule behavior. New microscopes based on fiber laser technology operate without the need to label the molecules.

Design of the new fiber laser microscope

A team of researchers from Germany and China designed a microscope that includes a unique compact fiber laser instead of the solid-state laser systems that used to be applied. The microscope based on fiber laser technology produces less noise than conventional designs, allowing them to be used in operating rooms.

Advantages of fiber laser microscopy

Label-free microscopy in biomedical research

Usually, staining with fluorescent markers can not be performed on in vivo tissues; label-free microscopy plays a crucial role in understanding how different new types of cells develop from stem cells, as well as in differentiating a tumor from normal tissue without staining. Fiber lasers allow researchers to operate without markers in the muscle tissue cells of the heart and liver, as well as other cells.

Comparison with solid-state laser systems

Advanced fiber laser systems find their wide application in optical nanomicroscopes, in which laser beam light is transmitted through glass fibers rather than through a solid body of crystal or glass. Previously, solid-state laser systems surpassed fiber lasers because of their higher power and less noise. Researchers used two synchronized optical resonators (laser beam cavities), the wavelengths of which were required to hit the specimen through the lens at the same time, resulting in challenging control of the whole process.

Practical benefits of the new system

The developed fiber laser microscope presents an essential benefit that includes easier operation than a conventional solid-state laser system. This fiber laser system is less subject to error, and the process becomes faster because it does not need to label the molecules. The prototype of the fiber laser microscope promotes the development of portable devices that can be applied in the operating room, for example, to mark tumor borders during an operation.

Future applications in medicine

The new fiber laser technology provides benefits for numerous biomedical applications, and the early detection of tumors is only one specific example of this. It is planned to employ the new fiber laser microscope in clinical applications in the near future, because preliminary studies have already been conducted and demonstrated amazing results.