Single Wavelength EDFA DFB single-wavelength butterfly laser 1550nm Single Wavelength Laser 1310nm Single Wavelength Laser Single-mode Single Wavelength Laser Benchtop Single Wavelength Laser Polarization-Maintaining Single Wavelength Laser DFB Single Wavelength Laser 1064nm single wavelength laser (pumped laser) 980nm Single Wavelength Laser (Pumped Laser ) Single Wavelength Laser