SOS2 Large-Core Fiber is a high-performance optical fiber designed for medical laser delivery, offering large core diameters, biocompatible coatings, and sterilization compatibility for hospital use.

Overview

Large-core fibers, such as SOS2, are optical fibers with core diameters significantly larger than standard telecom fibers, typically ranging from 200 µm to 550 µm, which allows them to transmit high-power laser energy efficiently with minimal nonlinear effects or material damage . These fibers can be multimode or single-mode, depending on the application, and are often used in medical laser procedures including BPH surgery, laser lithotripsy, endovenous laser therapy, and photodynamic cancer therapy .

Fiber Construction and Coatings

SOS2 fibers typically feature a pure silica core with a hard polymer cladding or other specialized coatings such as polyimide, silicone, acrylate, or Tefzel® . These coatings provide:

• Mechanical strength and resistance to micro-bending
• High-temperature tolerance (polyimide up to 400°C, silicone up to 200°C)
• Chemical inertness for safe use in hospital environments
• Ease of sterilization using autoclave, ethylene oxide (ETO), or radiation methods Secondary coatings or buffers, such as ETFE or nylon, are often applied for additional protection and to facilitate integration into medical assemblies .

Termination and End-Face Preparation

For hospital applications, fiber terminations are critical. SOS2 fibers are commonly terminated with SMA connectors at the proximal end, which can include mechanical or electronic interlocks for laser safety . The distal end can be:

• Cleaved or polished for standard light delivery
• Sculptured or side-firing tips for targeted tissue ablation
• Diffuser tips for uniform illumination in photodynamic therapy Proper end-face preparation ensures optimal laser power transmission and reduces the risk of fiber damage during procedures.

Applications in Hospitals

SOS2 large-core fibers are used in high-power laser delivery systems in hospitals, including:

• Urological procedures: BPH laser ablation, stone fragmentation
• Vascular treatments: Endovenous laser therapy, laser angioplasty
• Dental and oral surgeries
• Oncology: Photodynamic therapy with uniform light distribution The large core and high numerical aperture allow efficient light transmission, even under tight bending conditions, which is critical in surgical environments .

Key Advantages

• High-power handling with minimal loss
• Biocompatible and sterilizable coatings suitable for hospital use
• Customizable core sizes and fiber lengths for specific medical devices
• Durable and flexible for repeated clinical use
• Compatibility with a wide range of laser wavelengths from visible to 2.2 µm SOS2 large-core fibers are therefore a reliable choice for hospitals requiring safe, efficient, and high-performance laser delivery in various medical procedures.