Using noncritically phase-matched 1-cm(2) -aperture KTiOAsO(4) (KTA) crystals in an optical parametric oscillator (OPO), we have demonstrated a sustained average signal power of 33 W at 1534.7 nm. To our knowledge, this is the highest-average-power signal ever generated by an OPO. The pump source was a 100-Hz Q -switched 1064-nm Nd:YAG laser. Compared with that of the similar and more-common material KTiOPO>(4) , idler absorption in KTA is negligible, allowing high-power operation with minimal thermally induced refractive distortion in the OPO crystal.
We extend the operating regime of diode-pumped Nd:YAG lasers into the eye-safe region at 1.61 microm by using an efficient optical parametric oscillator in KTP. Total energy conversion efficiencies of the 1.06-microm pump to 1.61-microm signal and 3.1-microm idler approach 40%, with 25% converson to 1.61microm alone. This device has a wallplug efficiency of 0.8%, producing 2.5-mJ output energies at an eye-safe wavelength, and is readily scalable to higher energies.
We used a pair of diamond-turned CaF(2) aspheres to convert the pure TEM(00) Gaussian spatial profile output of a diode-pumped Nd:YAG laser oscillator into a super-Gaussian intensity profile with a nearly flat phase front. The resulting super-Gaussian beam was nearly diffraction limited with an M(2) of 1.75; in the near field the 5-mm diameter beam retained a nominally flat-top intensity distribution without significant diffraction peaks for an excellent working distance of more than 50cm. A 10% improvement in amplifier-energy extraction obtained by use of the reshaped beam is demonstrated.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.