Keysight / Agilent / HP 81000BA Barefiber Ring Adapter

The Keysight/Agilent/HP 81000BA Barefiber Ring Adapter is a specialized accessory that enables direct coupling of bare optical fibers to optical test equipment without connectors or polishing. The ring adapter interfaces with bare fiber holders and optical heads to facilitate temporary connections in laboratory and production environments where frequent fiber access and rapid reconfiguration are required.

– Technical Specifications

• Fiber Cladding Diameter: 125 µm
• Adapter Type: Bare fiber ring adapter
• Optical Head Series Compatibility: 815xxx and 816xxx series optical heads (8152x and 8162x)
• Optical Head Form Factors: Compatible with 5 mm and 3 mm optical heads when using integral D-shape connector adapters; also compatible with high-power optical heads

– Key Features

• Eliminates need for traditional fiber connectors and polishing processes
• Provides secure, stable connections that minimize signal degradation
• Enables precise alignment for repeatable measurements
• Designed for minimal signal loss in fiber optic coupling applications
• Supports both standard and high-power optical measurement systems

– Typical Applications

• Temporary fiber connections in research and development laboratories
• Production-line testing of unterminated fibers requiring frequent access
• High-power optical applications demanding precision alignment
• Fiber optic testing with optical power meters and spectrum analyzers
• Environments where connectorized solutions introduce unacceptable insertion loss or mechanical complexity

– Compatibility & Integration

The 81000BA functions as part of the Keysight optical head adapter ecosystem. It pairs with bare fiber holders matched to 125 µm cladding diameter fibers and integrates with the broader 81000 series adapter family, which includes specialized adapters for FC/PC, SC/APC, LC, ST, MT-RJ, and MTP connectors.