Coherent, Inc. has expanded their Sapphire™ line of compact, CW, visible lasers with several ultra-narrow linewidth models. Specifically, these new Sapphire SF lasers are available at wavelengths of 488 nm and 532 nm, and feature single longitudinal output to achieve a linewidth of less than 1.5 MHz. They are offered with output powers of 20 mW, 50 mW, and 100 mW at 488 nm, and 20 mW, 50 mW, 100 mW and 150 mW at 532 nm. Independent of wavelength and power class, Sapphire SF lasers are identical in form, fit and function. They provide a high quality, diffraction-limited beam (TEM00, M²<1.1) with excellent pointing stability (< 5 µrad/°C), high power stability (< 2%) and low noise (< 0.25% rms from 20 Hz to 2 MHz).
Coherent Sapphire lasers are based on the company's unique, optically pumped semiconductor laser (OPSL) technology. This is a well-proven technology with over 25,000 units currently in the field. Moreover, OPSL technology features extremely low output noise because its short upper state lifetime completely eliminates the "green noise" that limits the noise performance of many other solid state-lasers. They also don't suffer from thermal lensing issues commonly found in frequency doubled DPSS lasers (e.g. Nd:YAG). Plus, OPSL technology is both wavelength and power scalable.
These new Sapphire SF lasers are ideal for research and OEM applications that require a narrow spectral linewidth and/or a long coherence length. Primary applications include Raman spectroscopy, Brillouin scattering, holography/stereography, interferometry, metrology, inspection, and remote optical sensing.