Design and Realization of a Miniaturized DFB Diode Laser-Based SHG Light Source With a 2-nm Tunable Emission at 488 nm

We present a concept and the realization of a diode laser-based second harmonic generation (SHG) light source at 488 nm with the capability of a spectral tuning over 2 nm (83 cm-1) and a stable SHG power at 30 mW. Wavelength tuning is carried out via a common heat sink temperature for the pump laser and the crystal for nonlinear frequency conversion. The compact diode laser module with a footprint of 25 × 5 mm2has no movable parts. This enables the implementation as an excitation light source into portable sensor systems such as handheld devices for in situ spectroscopic investigations.