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G657B3 Ultra Bend Insensitive Fiber - Mill Direct
China
Supplier's customization ability
- Drawing-based customization
- Sample-based customization
- Full customization
Minimum order quantity: 1 kilometers
Shipping total: To be negotiated
- Lead time:
- confirmed with the quotation
- Packaging:
- standard export packing
- Samples:
- available on request
Product details
Technical Specifications of G657B3 Ultra Bend Insensitive Fiber
| Property | Parameter | Description |
|---|---|---|
| Product Name | G657B3 Ultra Bend Insensitive Single-Mode Optical Fiber | Extreme bend-insensitive fiber for tight-space and harsh-environment installations |
| Fiber Category | ITU-T G.657.B3 / IEC 60793-2-50 B-657-B3 | Category B3 offers the highest bend tolerance within the G.657 family |
| Standard Compliance | ITU-T G.657B3, IEC 60793-2-50, TIA-492AAAE | Compliant with international single-mode bend-insensitive fiber standards |
| Core Diameter | 9.0 ± 0.4 µm | Standard SMF core compatible with G.652D splicing |
| Cladding Diameter | 125.0 ± 0.7 µm | Standard 125 µm glass cladding |
| Coating Diameter | 245 ± 5 µm (standard) / 200 ± 5 µm (reduced) | Dual-layer UV-cured acrylate coating; reduced coating available for tight-buffer designs |
| Attenuation | ≤ 0.40 dB/km @ 1310 nm; ≤ 0.30 dB/km @ 1550 nm; ≤ 0.40 dB/km @ 1625 nm | Low attenuation across O, C, and L bands per IEC 60793-2-50 |
| Macrobend Loss (R=5 mm) | ≤ 0.15 dB/turn @ 1550 nm; ≤ 0.45 dB/turn @ 1625 nm | Exceptional bend performance at 5 mm radius — key B3 differentiator |
| Macrobend Loss (R=7.5 mm) | ≤ 0.08 dB/turn @ 1550 nm; ≤ 0.25 dB/turn @ 1625 nm | Suitable for micro-duct, FTTH drop cable, and indoor wiring |
| Numerical Aperture | 0.20 ± 0.02 | Optimized for efficient light coupling and low splice loss with G.652D |
| Zero Dispersion Wavelength | 1300 nm – 1324 nm | Consistent chromatic dispersion performance per ITU-T G.657B3 |
| Proof Test Level | ≥ 100 kpsi (0.69 GPa) | Standard screening; 200 kpsi available upon request for harsh environments |
| Operating Temperature | -60°C to +85°C | Wide thermal range suitable for outdoor, industrial, and FTTA applications |
| Application | FTTH/FTTX last-mile, indoor wiring, micro-duct, MDU, data center, 5G fronthaul | Ideal wherever tight bends, small conduits, or space-constrained routing is required |
| Certification | RoHS, REACH, UL (cable-level), CE; available with TÜV and Telcordia GR-20 | |
| Packaging | Supplied on wooden or plastic reels; standard lengths 2.2 km, 4.4 km, or custom | Reel labeling includes fiber type, length, attenuation, and batch traceability |
| MOQ | 1 reel (≥ 2.2 km); bulk orders ≥ 50 km for preferential pricing | OEM and private-label options available for cable manufacturers |
G657B3 Ultra Bend Insensitive Fiber - Mill Direct
G657B3 ultra bend insensitive fiber represents the most advanced category of bend-tolerant single-mode optical fiber available on the market today, engineered specifically for deployment environments where tight routing radii and extreme bending conditions are unavoidable. Compliant with ITU-T G.657.B3 standards, this fiber delivers exceptional performance in fiber-to-the-home (FTTH), in-building wiring, and last-mile connectivity installations where conventional fibers would suffer unacceptable signal loss. With a minimum bend radius as low as 5 mm, it withstands installation stresses that would render standard G.652 or even G.657.A fibers inoperable. Telecom operators, contractors, and network integrators worldwide rely on G657B3 fiber to future-proof their infrastructure while reducing installation complexity. As a mill-direct supplier, we offer premium-grade G657B3 ultra bend insensitive fiber at cost-effective rates, backed by rigorous quality control at every stage of production.
What is G657B3 Ultra Bend Insensitive Fiber?
G657B3 ultra bend insensitive fiber is a single-mode optical fiber defined under ITU-T G.657 Category B, Sub-category 3. It is specifically optimized for ultra-tight bend applications, tolerating bend radii down to 5 mm with macrobending loss not exceeding 0.15 dB per turn at 1550 nm wavelength. Unlike Category A fibers, G657B3 is not required to maintain full compatibility with G.652 fiber, allowing its refractive index profile to be more aggressively optimized for bend resistance. It finds extensive application in dense urban FTTH drop cables, riser installations, and confined-space optical routing.
G657B3 Ultra Bend Insensitive Fiber Manufacturing Process
The production of G657B3 ultra bend insensitive fiber begins with the fabrication of a specially engineered preform using the Modified Chemical Vapor Deposition (MCVD) or Outside Vapor Deposition (OVD) process. A trench-assisted or hole-assisted refractive index profile is precisely constructed around the core to suppress light leakage during bending. The preform is then drawn at temperatures exceeding 2,000°C into fiber with a nominal outer diameter of 125 ± 0.7 µm, followed by dual-layer UV-cured acrylate coating application to achieve a final coating diameter of 245 ± 5 µm, ensuring mechanical durability and environmental protection.
G657B3 Ultra Bend Insensitive Fiber Technical Specifications
Our G657B3 ultra bend insensitive fiber meets or exceeds all ITU-T G.657.B3 requirements. Key parameters include: attenuation ≤ 0.4 dB/km at 1310 nm and ≤ 0.3 dB/km at 1550 nm; macrobend loss at 10 mm bend radius ≤ 0.03 dB/turn at 1550 nm and ≤ 0.1 dB/turn at 1625 nm; macrobend loss at 7.5 mm bend radius ≤ 0.08 dB/turn at 1550 nm; macrobend loss at 5 mm bend radius ≤ 0.15 dB/turn at 1550 nm. Mode field diameter measures 6.3–9.5 µm at 1310 nm, with a cutoff wavelength ≤ 1260 nm. Proof test level is 0.69 GPa (100 kpsi) as standard, with higher proof test options available upon request.
Get a Competitive Quote for G657B3 Ultra Bend Insensitive Fiber
Partner with our mill-direct team to source superior-quality G657B3 ultra bend insensitive fiber at the most competitive pricing for your project scale. Whether you require small evaluation quantities or large-volume bulk orders, our technical team is ready to deliver customized solutions with fast lead times and full documentation support.
- 24/7 customer support available
- Free samples for quality evaluation
- Competitive pricing for bulk orders
- Professional technical consultation
Contact us today to get your free quote within 24 hours!
