A Laser System containing a Fiber amplifier for boosting the output power.

The term master oscillator Fiber Amplifier (MOFA, MOPFA, or fiber MOPA) is a variation of the term power Amplifier">Master Oscillator Power Amplifier (MOPA), meaning a system where the power amplifier is a fiber amplifier. The latter is usually a cladding-pumped high-power amplifier, often based on an ytterbium-doped fiber.