Abstract

The choice of wavelength division multiplexer (WDM) couplers for use in fiber-based optical amplifiers is extremely important to obtain optimum device performance. At a minimum, these devices need to have low insertion loss at the doped-fiber pump and signal wavelengths, λ_p and λ_s. Small splice losses between the coupler input pigtail and the incoming telecommunication fiber at λ_s and between the coupler output pigtail and the Er-doped gain fiber at λ_s and λ_p are important to maximize amplifier signal-to-noise and to efficiently use available pump power. In addition, in high-gain amplifier applications, coupler backscatter and crosstalk may also impact noise. Finally, as practical amplifiers tend towards smaller physical size, bend induced loss in the coupler pigtails also becomes an important factor.

© 1990 Optical Society of America