Laser modules in optical pumping and optical trapping

Laser modules

Laser modules are applied in various industrial fields due to the wide spectrum of produced wavelengths. High-power fiber laser systems are commonly used for welding, marking, cutting, etc. Low-power but more precise fiber lasers are suitable for applications requiring high accuracy, for example, in science and medicine.

This article focuses on two applications of low-power fiber laser modules: laser pumping and optical trapping.

Most Common Advantages of Laser Modules

Laser diodes are applied in optical pumping of fiber lasers and DPSS. They are highly effective, robust, and compact. Laser modules provide high peak energy and stable beam quality.

The principle of photon confinement in rare-earth doped fiber gives fiber lasers an advantage: stability. Since a fiber laser generates the beam within the core, it does not require complex or sensitive optical components. Conventional lasers, on the contrary, rely on optical fibers for beam regulation and mirror reflection, which demand frequent precise adjustments. Fiber lasers are less sensitive to vibrations and shocks, maintaining operational stability.

The doped fiber core limits the beam, ensuring higher accuracy and more effective focusing.

Energy efficiency is another strength of fiber lasers. They convert almost all input into the beam, minimizing thermal conversion. This improves thermal protection and reduces degradation.

Most conventional laser sources use water cooling, while fiber lasers use air cooling to dissipate heat. This improves portability and reduces power consumption. Modern air-cooling systems, based on advanced heat dissipation studies, have proven highly effective in mitigating thermal effects.

Fiber laser systems with 1–100 W output power offer a wide range of wavelengths.

Fiber Laser Systems in Optical Pumping

Optical pumping of a laser medium is illumination by an external light source to transfer it to an excited state. Fiber lasers, like all laser systems, require an excitation source to pump energy into the system.

Methods of Optical Pumping

The most common methods of optical pumping include semiconductor lasers (diodes), solid-state, and fiber lasers. Both solid-state and fiber lasers are pumped with diodes.

Pumping can be continuous or pulsed. The difference lies in the delivery method: the pumping source is connected to the fiber core and fused into a double-clad fiber. The cladding material determines whether the absorption band is wide or narrow. Depending on this, conventional or wavelength-stabilized diodes may be applied.

Fiber Laser Modules in Optical Trapping

Optical trapping uses a focused laser beam to hold and manipulate microscopic objects. This technology is widely used in biomedical research.

Applications in Biomedical Research

Optical trapping can study single molecules thanks to its ability to work with nanoparticles. This has greatly advanced research on DNA and proteins.

Most optical trapping systems use laser modules with a 1 μm wavelength, which reduces the risk of biological damage. This range is optimal for aqueous biological specimens with a low absorption coefficient.

Synergy of Optical Pumping and Trapping

Together, optical pumping and optical trapping enable innovative applications in micro- and nanotechnology. Their combined efficiency brings new opportunities to science.

Fiber laser systems for multiphoton microscopy

Fiber laser systems

Overview of fiber lasers

Fiber lasers have evolved over the last years, becoming a significant force in manufacturing and high technology.

Fiber laser technology continues to expand its limits across various applications. High-power lasers transform the machining industry and economy, while low-power, highly accurate fiber lasers are used in medicine, biotech, and physical sciences.

The popularity of fiber lasers is due to their benefits, such as reliability, usability, and operational stability.

What is multiphoton microscopy?

Multiphoton microscopy is a laser scanning microscopy method. It uses as few as two or three photons combined to generate high-resolution 3D images of microscopic samples.

Applications in biological sciences

Laser microscopy has become an instrument in material studies. It is mostly applied in biological sciences and tissue engineering. Scientists use it to image living biological tissues at different scales, from molecular levels to the whole organism.

During experiments, multiphoton microscopy (MPM) provides accurate measurements of biological activities. Procedures can last from seconds to months, which may cause discomfort for patients. Minimal invasion is crucial while providing precise results.

This far-field imaging is developing rapidly and requires advanced fiber lasers. Further progress will expand multiphoton microscopy capabilities to observe biological processes in deep tissue layers with minimal damage.

Fiber laser systems in multiphoton microscopy

Fiber lasers are essential for multiphoton microscopy. Compared to conventional lasers, fiber laser modules have several advantages.

Advantages of fiber lasers

Without a separate optical medium for beam delivery, fiber lasers are more stable and easier to maintain, offering high optical gain.

Compared to traditional CO2 lasers, fiber lasers have higher power conversion rates and are energy efficient.

The highly focused narrow beam allows fiber laser modules to be applied in complex designs requiring high precision.

Fiber lasers have no moving parts that require regular maintenance.

Fiber laser systems can be more expensive than other lasers. However, their advantages reduce ownership costs. Lower maintenance and reduced power requirements also help lower operating costs.

Applications of fiber laser systems in multiphoton microscopy

Due to modern fiber lasers’ abilities, the technology continues to develop and explore its limits.

Multiphoton microscopy is applied in many medical and biological fields.

Fiber lasers for oncology

Multiphoton microscopy is an effective imaging tool for detecting malignancy. It can help specialists evaluate bladder tissue in real time. Along with bladder cancer, it is also used for prostate cancer evaluation. This procedure uses fiber lasers and requires preliminary analysis.

Fiber laser systems for immunology

Multiphoton microscopy images cells in vivo effectively, requiring precise fiber lasers that create contrast in scattering tissue while reducing phototoxicity and photobleaching. Immunology benefits from this technique, for example, through intravital imaging of leukocytes at the single-cell level.

Tracking cell migration, cell interactions, and intracellular signaling has become possible due to modern multiphoton microscopy. Previously limited to specialized labs, this technique is now widely available.

Fiber lasers for neuroscience

Multiphoton excitation with fiber laser pulses allows high-resolution imaging. With the growing role of microscopy, fiber lasers have proven to be highly suitable.

Neuroscience is a modern research area. Specialists study neuronal networks to understand brain pathologies and develop treatments for neurodegenerative diseases. Scientists can now analyze brain activity during visual tasks and operations. Observing brain function is necessary for understanding pathological conditions.

Deep brain imaging supports these studies. Designing fiber lasers requires considering factors like proper volume. Greater depth can reduce image quality. Fiber lasers are suitable for neuroscience due to their power scalability.

Laser modules for spermatogenesis

Multiphoton microscopy enables visualization of biological processes in live tissues. For spermatogenesis, it uses fiber lasers to visualize all tubules, with and without sperm.

Recent developments have allowed this sperm extraction technology to replace conventional testis biopsies. Specialists continue to improve it. Tubule retrieval now relies on appearance, and multiphoton microscopy may further enhance real-time visualization for clinical use.

Overall, fiber laser systems are suitable and effective for multiphoton microscopy, expanding the boundaries of science and medicine. Multiphoton microscopy with fiber lasers supports treatment development for diseases like epilepsy and Parkinson’s.

Low-power fiber laser systems in medicine

Fiber laser systems

Overview of low-power fiber lasers

Nowadays, fiber laser systems show significant growth and advantages in industries such as aerospace and automotive.

Less powerful fiber lasers have also found applications. One such field is medicine, which benefits from fiber lasers in various treatments and procedures.

This article focuses on two of these applications: photoacoustic imaging and tissue engineering.

Fiber lasers for photoacoustic imaging

Fiber laser systems play a crucial role in photoacoustic imaging and suit this technology due to their compact size and high sensitivity. The sensors with fiber lasers resist environmental disturbances such as temperature and pressure changes. Fiber lasers resolved several issues present in traditional sensors.

Photoacoustic imaging is commonly used for endoscopy and intravascular applications, requiring highly precise fiber laser-based sensors.

Photoacoustic tomography, a branch of photoacoustic imaging, provides high-resolution, non-invasive imaging. It is widely accepted by specialists and patients and is of high interest due to its applications in life sciences and disease diagnosis.

Overall, photoacoustic imaging has great potential for medical treatments compared to electrical ultrasound. Modern fiber laser modules and sensors are powerful instruments for this technique.

Fiber lasers for tissue engineering

Another development area of fiber laser systems is tissue engineering. Modern fiber laser technology allows creating biological systems by arranging biomaterials and living cells.

Role of fiber lasers in tissue engineering

Tissue engineering would not be possible without precise and robust technology. Modern fiber lasers use contemporary computer technologies to structure living and nonliving materials. This technology enables precise manipulation of cells and complex tissue constructions, which are applied in cell biology studies, regenerative medicine, and more.

Tissue engineering combines engineering and life science principles. It develops alternatives to improve or restore tissues or organs. The goal is to build artificial solutions that closely imitate natural biological environments, allowing cells to function in artificial or real tissue.

Future development of tissue engineering technology

In the future, scientists aim to design artificial biological structures that are highly functional with cells arranged at high temporal and spatial resolution. Cell engineering will use interactions of different cell types to create microenvironments closely resembling real organs.

Recent applications of fiber laser systems demonstrate unique features in regenerative medicine and other medical devices.

Today, advanced fiber laser systems enable precise manipulation and imaging. Specialists can apply modern fiber laser technology in medical fields such as photoacoustic imaging and tissue engineering.

Fiber laser modules in various fields of medicine

Laser Modules

Since the creation of the first laser modules, specialists have conducted extensive research on the effects of laser radiation on biological tissues. Fiber lasers have contributed to developing various treatment methods for different diseases.

The main advantages of fiber laser modules in medicine

Depending on radiation power, laser modules can be used for heating, cutting, or coagulation of biological tissue.

Key benefits

Advantages of medical instruments with fiber lasers compared to traditional equipment:

  • fiber lasers allow non-invasive or minimally invasive cuts;
  • high temperatures sterilize wounds, reducing infection risk;
  • minimal wound swelling;
  • reduced postoperative complications;
  • shorter recovery period.

Today, fiber lasers are applied in otorhinolaryngology, vascular disease treatment, cardiac surgery, orthopedics, traumatology, neurosurgery, gynecology, proctology, dentistry, and other fields.

Fiber lasers’ radiation levels and applications

Different effects of fiber laser radiation on biological tissues depend on the wavelength. This is determined by the absorption coefficient, scattering coefficient, and moisture content. Absorption affects penetration depth. Water and hemoglobin are the main absorbers in biological tissues.

Common radiation ranges

Common radiation ranges used in medicine:

  • 0.94–0.98 µm radiation provides an optimal balance of cutting and coagulation in surgery;
  • 1.06 μm radiation is used for controlled volumetric tissue heating;
  • 1.4–1.8 μm wavelength is mainly for water heating to 100 °C and evaporation;
  • 1.8–2.1 μm wavelength, like CO2 lasers, offers good cutting, minimal thermal damage, and effective coagulation;
  • Lasers with wavelengths >2 μm are widely used. Wavelengths between 2.05–2.3 µm operate in the atmospheric transmission window and are used where eye safety is critical.

Thulium-doped fiber lasers provide 1900–2000 nm wavelengths, matching absorption peaks in biological tissues:

  • Fiber lasers up to 10 W are used in cosmetology and dentistry;
  • 40 W lasers are applied in gynecology, proctology, and vascular treatments;
  • 50–120 W fiber lasers are used in urology for transurethral prostate vaporization.

Features of fiber lasers’ use in medicine

Fiber lasers are used in many technical and scientific fields. They are compact, resistant to vibrations and electromagnetic interference, and can be equipped with various commercially available components.

Individual approach and surgical applications

Each pathology requires an individual approach. Specialists set the appropriate laser modes for each medical field. Fiber lasers help reduce surgical injuries and shorten recovery time. Fiber lasers are important in modern endoscopic surgery and are fully compatible with surgical endoscopes, enabling minimally invasive procedures.

Today, fiber laser modules are widely used in biology and medicine. Future research will focus on laser effects on natural and artificial tissues and on optimizing laser parameters.