Pulsed diode laser sources in the yellow-green spectral range are highly demanded for applications like label-free imaging or stimulated emission depletion (STED) microscopy. However, direct emitting diode lasers are not yet providing sufficient emission characteristics and lifetime behavior. In this work pulsed laser sources that make use of reliable near infrared diode lasers in the wavelength range from 1122 nm to 1178 nm and single-pass second harmonic generation are presented. A ridge waveguide laser with integrated distributed Bragg-reflector (DBR-RWL) is operated in gain-switched pulsed operation. The laser pulses are further amplified by a subsequent tapered amplifier (TPA) in a master oscillator power amplifier (MOPA) configuration. Here, the TPA is in cw-operation. The amplified laser pulses are then coupled into a periodically poled lithium niobate ridge waveguide crystal. The whole setup fits into a butterfly housing with a footprint of only 47 mm × 76 mm which also supports a polarization maintaining fiber output. The concept has been realized at emission wavelengths of 561 nm and 589 nm, respectively. At 561 nm laser pulses with a full width at half maximum (FWHM) of 100 ps and peak power of more than 2.5W could be demonstrated, which is a nearly tenfold increase compared to previous work without TPA. The pulses at 589 nm have similar temporal characteristics but slightly lower optical output power of more than 1W pulse peak power.
Distributed Bragg reflector tapered diode lasers (DBR-TPL) based on a quantum-well structure are presented, which emit at various wavelengths between 1100 and 1200 nm. Long lifetimes of these diode lasers are demonstrated. The lasers feature a high radiance facilitating a highly efficient second harmonic generation (SHG) in lithium niobate (PPMgO:LN) ridge waveguide crystals in a single-pass configuration. SHG output powers up to
0.86 W corresponding to SHG power densities in the ridge waveguide core > 1 MW/cm2 are achieved for nearly diffraction limited beams at wavelengths of 561, 578 and 589 nm. Absorption behavior at these power densities is investigated without observation of nonlinear absorption phenomena.
In this work three different concepts for micro integrated laser sources emitting light at 560 nm are investigated. The modules have different near infrared diode laser sources and different geometries of the crystals for second harmonic generation. The power emitted by the modules varies from 112mW achieved with a simple module with a ridge-waveguide laser and a ridge-waveguide crystal to 548mW coming from a module using a laser with subsequent amplifier and a planar-waveguide crystal. The article features a detailed description of the near infrared sources and the used crystals as well as the discussion of the complete modules.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.