Half-Watt single frequency yellow 561 nm and yellow-green 553 nm DPSS lasers with record 19% optical conversion efficiency
Oxxius 561 nm laser sources today
This 2010 SPIE paper presents the 561 nm single-frequency DPSS laser at half-watt output, achieved by frequency-doubling the weak 1123 nm Nd:YAG line in a monolithic cavity engineered to minimize intracavity losses. At the time of publication, Oxxius had already introduced the SLIM-561 at 100, 200, and 300 mW; this work pushed the architecture to 500 mW while simultaneously developing the 553 nm variant by doubling the 1106 nm Nd:YAG line.
The driver for this power scaling was twofold: biotechnical applications demanding higher excitation power for fluorophores such as TRITC, mCherry, and PE, and emerging metrology applications (particularly Laser Doppler Velocimetry) requiring both high power and single-frequency operation at 561 nm. The 561 nm wavelength has since become a standard excitation line in confocal microscopy, flow cytometry, and super-resolution imaging, where it optimally excites a broad range of yellow-orange fluorescent probes with minimal spectral overlap.
The SLIM series described in this paper evolved into the current LCX-561 single-frequency laser, which delivers the same monolithic cavity stability in a compact, OEM-ready format qualified for continuous operation in scientific and industrial instruments.
Abstract
Since the first introduction of DPSS lasers at 561 nm in 2004, the power level required by some biotechnical applications has always increased. Oxxius has contributed to fulfill the demand thanks to the introduction of the SLIM-561 100mW in 2008 and of the SLIM-561 200mW and 300mW in 2009. More recently, new dyes or nano-dots have required shorter wavelengths (such as 553 nm) and new applications such as Laser Doppler Velocimetry requiring both high power and single frequency operation have appeared. In this presentation, we demonstrate how to further increase the power. 553nm and 561 nm emission are obtained by frequency doubling the 1106 nm and 1123 nm lines of Nd:YAG. The latter transitions are significantly weaker than the 1064 nm line. As a consequence, any loss in the cavity significantly increases the laser threshold. Because of the perfect alignment of the crystal interfaces and the …