The 2940 nm mid-infrared laser acts as an irreplaceable "gold standard working wavelength" in high-end minimally invasive medical care, precision special microfabrication, mid-infrared photoelectric detection and cutting-edge scientific research. This wavelength precisely matches the strong absorption peaks of water molecules and hydroxyl groups, delivering ultra-shallow tissue penetration depth and an extremely small thermal diffusion range. It serves as the core light source for non-destructive, cold-state and fine processing as well as minimally invasive diagnosis and treatment.
As a new-generation core gain unit for solid-state lasers, the Er:YAG side-pumped module adopts a side pumping architecture with semiconductor laser chips, thoroughly addressing the technical drawbacks of traditional xenon lamp pumping and end-pumping schemes. Characterized by high stability, high electro-optical conversion efficiency, ultra-long service life and excellent beam quality, it has become the mainstream core device for commercialization, miniaturization and high-precision mass production of mid-infrared laser equipment.
Er:YAG (erbium-doped yttrium aluminum garnet) crystal is a dedicated gain medium optimized for 2940 nm output. Its unique energy level transition characteristics enable stable emission of 2940 nm mid-infrared laser. Laser at this wavelength is rapidly absorbed by water in substances, with an effective penetration depth of only 2–5 μm. Laser energy concentrates on the material surface layer, resulting in minimal thermal conduction and thermal damage confined to the micrometer scale, perfectly realizing cold processing, non-invasive treatment and low thermal injury.
Different from conventional end-pumping structures widely used in the industry, this product adopts an annular side pumping design with multiple arrays of semiconductor laser chips. Multiple groups of laser diode arrays are evenly arranged around the circumference of the Er:YAG crystal rod, paired with inner sleeves to couple pump light uniformly into the crystal sidewall.
This structure greatly expands the pump receiving area, completely eliminating the pain points of end-pumping structures such as single-side light incidence, uneven pumping, large radial thermal gradients and limited maximum output power. It effectively optimizes the internal optical field distribution of the crystal, suppresses thermal lens effect and thermal depolarization, and significantly improves the uniformity and stability of laser output.
Benefiting from micrometer-level ultra-low thermal damage, the 2940 nm Er:YAG laser module features zero mechanical vibration and controllable thermal radiation range. It is widely deployed in high-end minimally invasive medical departments including dentistry, medical aesthetics, otolaryngology and orthopedics. Compared with traditional mechanical instruments and ordinary laser surgery, it brings smaller wounds, faster postoperative recovery and better patient experience.
Dental field: It can complete caries removal, enamel polishing, root canal preparation, implant bone trimming and other procedures in one go. Free of vibration and noise, it well protects surrounding healthy tissues, reduces anesthetic dosage, relieves patients’ fear of treatment and improves clinical safety and comfort.
Medical aesthetics: With precisely controllable pulse energy, it supports fractional skin rejuvenation, scar and stretch mark repair, pigment spot vaporization and other treatments. Its narrow thermal damage zone creates thin postoperative scabs and rapid recovery, lowering risks of pigmentation and meeting market demands for light medical beauty with short downtime.
Endoscopic minimally invasive surgery: When matched with fiber coupling and endoscopic systems, the module delivers precise soft tissue ablation and cutting inside body cavities. It generates tiny surgical wounds with minimal bleeding, avoids mechanical extrusion damage, maximizes preservation of healthy tissues and shortens rehabilitation periods, satisfying all kinds of refined minimally invasive diagnosis and treatment.
In household health testing, the 2940 nm Er:YAG laser is primarily used for minimally invasive blood sampling blood glucose meters. It replaces traditional metal lancets to achieve needle-free micro blood collection, and cooperates with test strip enzymatic reactions to measure blood glucose with accuracy equivalent to conventional needle sampling devices.
Classified as a water laser, its absorption coefficient in skin stratum corneum and tissue moisture is 15 times that of CO₂ lasers. Laser energy is instantly absorbed by surface moisture with penetration depth limited to 0.1–0.2 mm, acting only on the epidermal stratum corneum. Instant high-temperature vaporization creates micrometer-sized pores without tearing the skin. Since pain nerves and capillaries are distributed in the dermis below 0.2 mm, the laser will not stimulate pain nerves, bringing only mild burning sensation during blood collection. Trace blood can seep out via tissue negative pressure. Meanwhile, high laser temperature sterilizes the wound, eliminating the need for alcohol disinfection.
This technology avoids safety hazards such as broken needles and cross-infection with less pain, suitable for long-term blood glucose monitoring of children and needle-phobic populations. The tiny sampling pores heal rapidly with barely visible pinholes or bruising. Besides, measurement results are unaffected by skin pigment or tissue moisture, delivering outstanding testing stability.
For hydroxyl-containing non-metallic special materials and biomaterials, 2940 nm laser offers exclusive absorption advantages to realize high-precision microfabrication free of edge chipping and thermal damage.
Widely applied in precision drilling, surface texture modification and microstructuring of bioceramics, artificial bones and dental restoration ceramics, solving cracking and breakage problems of traditional mechanical processing.
Suitable for microchannel etching and cutting of hydrogel biochips, medical polymer films and flexible biomaterials without damaging biological activity or substrate integrity.
Also adopted in fine micro-carving of jade, non-destructive surface cleaning of cultural relics and precision coating stripping, featuring high processing accuracy and excellent yield to meet mass production requirements of high-end precision manufacturing.
Beyond the core 2940 nm wavelength, the Er:YAG laser can generate a derivative 1645 nm eye-safe infrared band with no intense light radiation hazard and excellent atmospheric transmittance. It fits optoelectronic equipment such as UAV topographic mapping systems, long-distance ground laser rangefinders, space debris detectors and atmospheric environmental monitoring devices.
Moreover, the module can serve as a stable pump source for OPO (Optical Parametric Oscillator) and Raman frequency conversion systems to expand broadband mid-infrared output of 3–5 μm for gas concentration detection of methane, water vapor, VOCs and other volatile organic compounds.
For universities and research institutes, it acts as a stable core light source for mid-infrared molecular spectroscopy research, laser nonlinear optical experiments and laser-induced damage threshold testing of optical components, with controllable output parameters and high repeatability to fully satisfy high-precision experimental demands of frontier scientific research.
The Er:YAG side-pumped module integrates long service life, highly stable output, lightweight structure, advanced thermal management and strong replaceability. It not only fully replaces traditional xenon lamp pumping equipment, but also effectively overcomes inherent drawbacks of end-pumped modules including low maximum power and severe thermal distortion, making it an ideal upgrade solution for industrial and medical laser systems.
