The OS 4500 is a compact, all-in-one continuous-wave laser source combining excellent spectral properties with an extremely large tuning range. Features like  Single Frequency Operation Narrow Linewidth Low Noise Outstanding Beam Quality make it the ideal tool for high-resolution spectroscopy and many other applications requiring precision metrology in the infrared spectral region. The OS 4500 system is an optical parametric oscillator (OPO) compley equipped with control and stabilization electronics as well as an integrated pump laser. Its output is converted into signal and idler radiation in a nonlinear crystal (periodically poled, MgO doped lithium niobate). The crystal is placed inside an optical resonator which forms the actual OPO. An intra-cavity etalon (ICE) ensures stable singl e-frequency operation. The large emission range for signal (1.38 - 2.00 μm) and idler (2.28 - 4.67 μm) radiation is achieved by integrating several poling periods on a single crystal. The system can be tuned to the desired emission frequency without changing optical components. Tuning can be performed on several levels: Coarse tuning is done by manually changing the lateral position of the nonlinear crystal to select a suitable grating. Temperature tuning is then used to find the desired wavelength within one grating.  Etalon tuning selects the desired cavity mode of the resonated radiation within the gain bandwidth of the OPO. Continuous tuning without mode-hops is performed by changing the frequency of the pump laser. | 
