Keopsys CYFA-BO / CYFA-PB / CEFL-L-PB-HP / CEFA-C-WDM-LP / CTFA-PB Series Fiber Amplifiers

Overview

Keopsys fiber amplifiers are high-performance, turnkey optical amplification solutions engineered for demanding scientific, industrial, and defense applications requiring stable, low-noise, and polarization-controlled signal boosting across key telecom and non-telecom wavelength bands. Based on double-clad rare-earth-doped fiber architecture and optimized pump laser diode integration, these amplifiers operate under either continuous-wave (CW) or pulsed excitation regimes—enabling precise control over gain, noise figure, and temporal fidelity. The product family spans five core platforms: Ytterbium-doped amplifiers for the 1 µm region (CYFA-BO and CYFA-PB series), Erbium-doped L-band and C-band amplifiers (CEFL-L-PB-HP and CEFA-C-WDM-LP), and Thulium-doped amplifiers for the 2 µm mid-infrared window (CTFA-PB). Each platform is available in both free-running and polarization-maintaining (PM) configurations, supporting coherent detection, interferometric sensing, and nonlinear frequency conversion setups where state-of-polarization stability is critical.

Key Features

• Multi-band coverage: Native operation across 1060–1090 nm (Yb), 1100–1120 nm (extended Yb), 1527–1566 nm (C-band), 1565–1605 nm (L-band), and 1900–2000 nm (Tm)
• High saturation output power: Up to +42 dBm (15.8 W) for Yb-based CW amplifiers; +33 dBm (2 W) for L-band and Tm amplifiers; +23 dBm (0.2 W) for low-power C-band gain-flattened modules
• Integrated pre-amplification stage in CYFA-PB, CEFL-L-PB-HP, CTFA-PB, and CEFA-C-WDM-LP models—enabling operation with input powers as low as –20 dBm while maintaining >30 dB small-signal gain
• Polarization-maintaining (PM) variants featuring >20 dB PER (polarization extinction ratio) and alignment-matched PM fiber pigtails for seamless integration into interferometers and quantum optics systems
• Thermally stabilized pump diodes and all-fiber, fusion-spliced architecture ensuring long-term power stability (35% wall-plug efficiency typical)
• Comprehensive safety compliance: Certified to IEC 60825-1 Class 4 laser product requirements with integrated interlock circuits, emission indicators, and key-controlled enable logic per EN 61326-1

Sample Compatibility & Compliance

These amplifiers are compatible with standard single-mode (SMF-28), polarization-maintaining (PANDA or Bow-tie), and large-mode-area (LMA) passive fibers. Input/output interfaces use FC/APC or FC/PC connectors with optional customized fiber types (e.g., Nufern PLMA-YDF-25/400 for high-peak-power pulse amplification). All units conform to EU RoHS Directive 2011/65/EU and carry CE marking under the Machinery and EMC Directives. For regulated environments—including pharmaceutical laser processing, aerospace LIDAR calibration, and GLP-compliant optical metrology labs—the amplifiers support optional firmware logging of operational parameters (pump current, case temperature, output power) traceable to NIST-traceable photodiode calibrations. While not FDA-cleared as medical devices, their design aligns with ISO 13485-aligned manufacturing practices and supports audit-ready documentation packages upon request.

Software & Data Management

Local monitoring and control are implemented via RS232, USB-C, or optional Ethernet (TCP/IP) interfaces. The Keopsys Control Suite (v3.2+) provides GUI-based configuration of gain setpoint, automatic power stabilization mode, alarm thresholds, and real-time oscilloscope-style plotting of output power transients. All communication protocols adhere to SCPI (Standard Commands for Programmable Instruments) syntax, enabling native integration into LabVIEW, MATLAB, Python (PyVISA), and EPICS-based control frameworks. Critical operational events—including pump fault, over-temperature shutdown, or interlock break—are logged with timestamps and retained in non-volatile memory for post-event diagnostics. Audit trails comply with ALCOA+ principles when used in conjunction with validated host software meeting FDA 21 CFR Part 11 requirements for electronic records and signatures.

Applications

• High-power seed amplification for ultrafast Ti:sapphire and fiber CPA systems
• Coherent LIDAR transmitters (Doppler wind sensing, vibrometry)
• Fiber-optic gyroscopes (FOGs) and distributed acoustic sensing (DAS) interrogators
• Mid-IR supercontinuum generation pumping at 2 µm
• CW and nanosecond-pulse amplification in spectroscopic absorption cells (e.g., CH₄, CO₂, H₂O detection)
• OEM integration into quantum key distribution (QKD) transceivers and atomic clock laser chains
• Test-bed amplification for DWDM channel characterization and EDFA gain spectrum mapping

FAQ

What is the typical noise figure for the CEFL-L-PB-HP amplifier at 1580 nm?
The measured noise figure is ≤5.5 dB under small-signal conditions (input < –25 dBm), consistent with theoretical ASE-limited performance for L-band EDFAs.
Can the CTFA-PB series be operated in gain-clamped mode for wavelength-division multiplexing applications?
No—CTFA-PB is a single-channel, forward-pumped amplifier optimized for narrowband or tunable 2 µm sources; gain clamping requires multi-stage architectures not present in this series.
Is analog modulation supported on the pump diode drivers?
Yes—models with analog monitor outputs (e.g., CYFA-PB-HP-A) support external voltage-controlled gain adjustment up to 10 kHz bandwidth using 0–5 V input.
Do you provide custom fiber pigtails with angled physical contact (APC) polish and specific length tolerances?
Yes—standard options include ±1 cm length tolerance and FC/APC connectors; tighter tolerances (±1 mm) and specialty fibers (e.g., SM2000, HI1060) are available under NRE agreement.
Are firmware updates provided free of charge during the warranty period?
Yes—Keopsys offers lifetime firmware updates at no cost, including security patches, new SCPI commands, and compatibility enhancements for emerging host platforms.