The fiber-coupled Laser Diode Beam Sources of type 51nano have reduced power noise (typ. < 0.15 % of Po (RMS, Bandwidth < 1 MHz)), reduced coherence length (≈ 300 µm) and low speckle contrast. They are available with polarization-maintaining or single-mode fiber cable. There are different series: 51nano-S and 51nanoFI-S (with integrated Faraday isolator to protect the laser source from back-reflection) as well as the OEM series 51nano-N and 51nanoFI-N.