940 nm 30 W Fiber-Coupled Laser Diode

The K940FAHHN-30.00W is a fiber-coupled laser diode delivering 30W of Continuous Wave (CW) output power at a center wavelength of 940nm (±10nm). Designed for fiber laser pumping, this compact module offers a high-brightness 105μm core output (0.22 NA) ideally suited for coupling into small-core double-clad gain fibers in low-to-mid power fiber laser and amplifier pump configurations.The most notable electrical characteristic of this laser diode is its ultra-low operating voltage of just 4.8V typical (5.4V maximum) — the lowest operating voltage in the entire 940nm and 976nm product lineup. This makes it directly compatible with 5V-rail OEM power supply architectures, significantly simplifying integration into compact devices, embedded systems, and battery-powered or low-voltage laser platforms without requiring a dedicated high-voltage laser driver. Despite this low voltage, the module maintains the same class-leading 52% electrical-to-optical efficiency as the 70W sibling.Like the 70W 940nm module, the K940FAHHN-30.00W features a **1400–1600nm feedback isolation band** — protecting the diode against back-reflected signal light in Er-doped and Tm-doped fiber laser systems operating in the telecom C and L bands. The 4-pin package includes an optional Thermistor (Pins 3 & 4) for junction temperature monitoring, and the fiber terminates bare (no connector) through 0.9mm loose tubing with a 1-meter pigtail and 50mm minimum bending radius.