Abstract

Applications like spectroscopy, interferometry and holography are in the need of long coherence lengths. Helium-neon (HeNe) lasers and semiconductor diode lasers have been used to address these applications, because these devices provide a narrow spectral linewidth. HeNe lasers are bulky and fragile due to their long resonator being made of glass. Small-sized diode lasers have a broad gain spectrum over several nanometers and a high reflective rear facet coating that is spectrally broad as well. Therefore, for diode lasers an external wavelength stabilization, which is usually a grating, needs to be realized on a micro-optical bench in order to preserve a small footprint of the device [1,2].

© 2013 IEEE