Patent ID: 11870205
Assignee: CYBEL, LLC.
Field: Optics (Instruments)
Classification: CPC H | IPC H

Claim 11:
12. A multi-stage optical amplifier for operation at an eye-safe input signal wavelength λS within the 2 μm region, comprising:
a plurality of N sections of Ho-doped optical fiber disposed in a concatenated configuration such that an input optical signal applied to a first amplifier stage propagates through the plurality of N sections of Ho-doped optical fiber and exits as an amplification optical output signal, each section of Ho-doped optical fiber characterized by a gain coefficient G(λ) and an absorption coefficient α(λ) that vary as a function of a wavelength of the pump light applied thereto; and
a pump source providing pump light at a defined absorption-dominant pump wavelength λP selected from a wavelength range of 1820 nm 20 1880 nm, where α(λP)>G(λP) regardless of the value of input signal wavelength λS within the 2 μm region, the pump light applied as an input to each amplifier stage of the multi-stage optical fiber amplifier.