Diode-pumped low noise CW 355-nm intra-cavity tripled laser up to 20 mW

This 2006 paper demonstrates a diode-pumped 355 nm intra-cavity laser delivering low-noise CW output up to 20 mW — the first reported efficient DPSS source at this wavelength, based on a Nd:YVO4 crystal optically contacted with KTP and LBO for intracavity second and third harmonic generation. The techniques described here remain foundational to Oxxius’s current CW & modulated UV laser sources, widely used today in flow cytometry, confocal microscopy, cell sorting, and semiconductor inspection.

Abstract

Low noise lasers in the UV spectrum (355 nm) are important for many applications like spectroscopy, confocal microscopy, flow cytometry, cell sorting, CD mastering, semiconductor inspection and reprographics. The UV CW laser sources currently commercially available, are restricted to excimers lasers, gas ions lasers which suffer from low power efficiency (0.01% or less), high electrical consumption and bulky dimensions. These products, which are expensive, are still waiting for practical replacements. To our best knowledge, we report in this paper the first efficient low noise diode-pumped neodymium doped solid-state laser operating at 355 nm by intra-cavity third harmonic generation (THG). The fundamental infrared laser light is generated by a diode-pumped Nd:YVO4 crystal optically contacted with others components of the laser cavity. Intra-cavity SHG and THG are achieved with a KTP and LBO respectively …