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Optically pumped quantum dot (QD)-based semiconductor disk lasers (SDLs) have been under intense research after their first demonstration and important enhancements of their parameters have been achieved since then. In this paper, we present recent developments in QD-based SDLs emitting in the 1-1.3 μm spectral region. Three different wavelength ranges of 1040, 1180, and 1260 nm were explored. Power scaling up to 6 W was achieved for 1040 and 1180 nm devices and up to 1.6 W for 1260 nm device. New spectral regions were covered by direct emission and frequency doubling was used to demonstrate spectral conversion into visible region with green, orange, and red light. Also, the broad gain bandwidth of QD materials was explored and wavelength tuneability up to 60 nm around 1040 nm, 69 nm around 1180 nm, and 25 nm around 1260 nm was demonstrated. The efficiency of excited and ground state emission in QDs was also compared. All these improvements allow new possibilities in applications of QD SDLs, reveal their potential, and suggest the aims for future research in the field.

Optical pumping of Raman fiber lasers and amplifiers with semiconductor disk lasers represents novel advantageous approach as compared with conventional pumping techniques based on diode lasers and/or fiber converters. Short pulse generation and low-noise amplification are experimentally demonstrated using this pumping concept. High-power, low-noise, and diffraction-limited beam quality, naturally attributed to disk laser geometry, promises significant and positive impact on the optical amplifier technology.

We report the fabrication and characterization of high-quality GaInNAs/GaAs gain mirror as an active media for semiconductor disk lasers emitting at the 12XX nm spectral range. The structure was fabricated by molecular beam epitaxy using a radio frequency plasma source for incorporating the nitrogen. The growth parameters have been optimized to reduce detrimental effects of nitrogen on the emission efficiency. Using the gain mirror, which comprised 10 GaInNAs quantum wells with a relatively low content of nitrogen, we demonstrated semiconductor disk laser with an output power of ∼5 W and a differential efficiency of ∼20%.

We demonstrate quantum-dot (QD)-based, optically pumped semiconductor disk lasers (SDLs) for wavelengths ranging from 950 to 1210 nm. QDs grown either in the submonolayer (SML) or in the Stranski–Krastanow (SK) regime are employed as active layers of the SDLs which are based on two different design concepts. Output power of up to 1.4 W continuous wave (CW) is achieved with an InAs/GaAs-SML SDL at 1040 nm. Up to 21 InGaAs SK-QD layers within a single SDL gain structure are used to realize the ground-state CW lasing with 0.3 W at 1210 nm. The SK-QD-based SDL shows temperature and pump-power stable emission. Threshold and differential efficiency do not depend on heat-sink temperature.

We present the optimization and performance of high-power optically pumped semiconductor disk lasers emitting near 940 nm. The emission efficiency at this wavelength is typically low owing to the poor carrier confinement within the shallow GaInAs quantum wells especially at high injection levels. Our work was focused on studying the efficiency of three types of structures with barrier materials made of AlGaAs, GaAs and GaAsP, providing different band offsets. The structures were grown by solid-source molecular beam epitaxy and consisted of a 30.5 pair AlAs/AlGaAs distributed Bragg reflector and an active region comprising 10 groups of triple-quantum-wells. To improve the crystal quality we have applied rapid thermal annealing for each grown wafer. The gain chips were then capillary bonded with water to a type IIa natural diamond heat spreader. The bonded gain elements were tested in a laser cavity with a linear-cavity configuration. Using a 3% output coupler we have obtained a maximum output power of 3 W from the structure with GaInAs/GaAsP composition. The corresponding M 2 value was 1.5 and the optical-to-optical conversion efficiency was 10%.

1.6 GHz repetition rate supercontinuum generation with a highly GeO 2 -codoped silica fibre is demonstrated. The fibre was pumped with a 1.57 μm modelocked semiconductor disk laser-fibre amplifier system. The continuum covered the spectrum from 1.35 to 2 μm with average output power of 3.5 W. This reported work provided the first demonstration of a supercontinuum generation using a modelocked semiconductor disk laser as a pump source.

In this letter, we present the first 2-W flip chip quantum-dot (QD) semiconductor disk laser operating at 1200 nm. Compared to other techniques used for thermal management, e.g., intracavity heat spreader approach, the flip chip design preserves undisturbed optical spectrum and exhibits low intracavity losses. The latter is particularly essential for power scaling of lasers with QD gain media.

An output power up to 5 W at 1.48-μm wavelength is achieved from an optically pumped semiconductor disk laser. An active region composed of an AlGaInAs/InP heterostructure grown on an InP substrate was wafer fused with an AlGaAs/GaAs Bragg reflector grown on a GaAs substrate. An intracavity diamond heatspreader bonded to the gain structure surface provides efficient heat removal from the active element. The results further validate that the wafer fusion technique offers a flexible platform for high-power disk lasers in a wide wavelength range.

Optically pumped wafer fused 1310 nm VECSELs have the advantage of high output power and wavelength agility. Gain mirrors in these lasers are formed by direct bonding of InAlGaAs/InP active cavities to Al(Ga) As/GaAs DBRs. We present for the first time Watt-level 1310 nm wafer-fused VCSELs based on gain mirrors with heat dissipation in the "flip-chip" configuration. Even though output power levels in this approach is lower than with intra-cavity diamond heat-spreaders, the "flip-chip configuration demonstrates higher quality optical emission and is preferable for industrial applications in optical amplifiers, intra-cavity doubled lasers, etc.

We report 1.3-μm mode-locked optically pumped semiconductor disk laser (SDL) made by wafer fusion. The gain medium and the saturable absorber, both based on an InP material system, were integrated with AlGaAs-GaAs distributed Bragg reflectors by localized wafer fusion. An intracavity wedged diamond heat spreader capillary bonded to the gain chip prevents the disruption of 6.4-ps pulse spectrum and supports 100 mW of average power. The results reveal an advantage of wafer fusion process of disparate materials over monolithically grown InP-based gain/absorber structures and demonstrate practical potential of the technique for long-wavelength SDLs.

We report on intracavity sum-frequency generation in a semiconductor disk laser operating simultaneously at the wavelengths of 986 and 1043 nm. An LBO crystal was used for nonlinear frequency conversion of the infrared radiation into the aquamarine sum-wavelength of 507 nm. Total converted power of 130 mW was obtained. The results suggest that a similar concept could be applied for difference-frequency generation to create a compact mid- infrared emitter operating at room temperature.

Quantum Dot based Semiconductor disk lasers are developed at 950 nm, 1040 nm, and 1210 nm wavelength. Up to 1.4 W output power and temperature independent cw-operation is demonstrated using different quantum dot growth techniques.

The potential for power scaling and wavelength scalability of semiconductor disk lasers (SDLs) makes them attractive for high-power single-frequency operation with numerous applications. In particular, single-frequency operation at 1.55 μm has been demonstrated with a monolithically grown InP-based SDL with 170 mW of output power at room temperature [1].

A single frequency wafer-fused semiconductor disk laser at 1.56 mu m with 1 watt of output power and a coherence length over 5 km in fiber is demonstrated. The result represents the highest output power reported for a narrow-line semiconductor disk laser operating at this spectral range. The study shows the promising potential of the wafer fusion technique for power scaling of single frequency vertical-cavity lasers emitting in the 1.3-1.6 mu m range. (C) 2013 Optical Society of America

The latest achievements of quantum dot based semiconductor disk lasers are reviewed. Several lasers operating at 1040 nm - 1260 nm were studied. All the structures were grown with molecular beam epitaxy on GaAs substrates. The number of quantum dot layers was varied and the gain was provided either by the ground or the excited state transition of the quantum dots. Frequency doubling of the lasers was demonstrated and the dual-gain laser geometry was found to be practical solution for intracavity frequency conversion. Intracavity heat spreader and thinned device heat management approaches are studied and compared.

Raman amplification has emerged as a promising gain material for multiple-wavelength lasers. Inhomogeneous broadening is a dominant mechanism of Raman gain broadening at room temperature which prevents the gain competition at closely spaced wavelengths [1]. Direct Watt-level core-pumping of single-mode fiber lasers with low-noise semiconductor disk lasers (SDL) demonstrated recently, represents a promising approach which allows to take an advantage of co-pumping scheme [2, 3].

A 1.3 µm Raman fiber amplifier pumped by 1.22 µm semiconductor disk laser in co-propagation geometry is demonstrated. Measured relative intensity noise of −148 dB/Hz over frequency range up to 3.5 GHz was measured at 900 mW of pump power. 9 dB gain was achieved with co-propagating pumping geometry with less than 2 dB additional noise induced by amplifier to the signal. Nearly shot-noise-limited operation of semiconductor disk laser combined with the diffraction-limited beam allows for efficient core-pumping of the single-mode fiber Raman amplifiers and represents a highly practical approach which takes full advantage of co-propagating pumping.

We demonstrate a frequency doubled dual-gain quantum dot semiconductor disk laser operating at 590 nm. The reflective gain element, grown by molecular beam epitaxy, has active region composed of 39 layers of InGaAs Stranski- Krastanov quantum dots. The gain mirrors produce individually 3 W and 4 W of output power while the laser with both elements in a single cavity reveals 6 W at 1180 nm with beam quality factor of M 2

1300-nm, 1550-nm and 1480-nm wavelength, optically-pumped VECSELs based on wafer-fused InAlGaAs/InPAlGaAs/GaAs gain mirrors with intra-cavity diamond heat-spreaders demonstrate very low thermal impedance of 4 K/W. Maximum CW output of devices with5 groups of quantum wells show CW output power of 2.7 W from 180 mu m apertures in both 1300-nm and 1550-nm bands. Devices with 3 groups of quantum wells emitting at 1480 nm and with the same aperture size show CW output of 4.8 W. These devices emit a high quality beam with M-2 beam parameter below 1.6 allowing reaching a coupling efficiency into a single mode fiber as high as 70 %. Maximum value of output power of 6.6 W was reached for 1300nm wavelength devices with 290 mu m aperture size.

Optically pumped semiconductor disk lasers with antiresonant design based on Stranski-Krastanow-grown quantum dots are demonstrated to extend the spectral coverage of such type of devices up to 1250 nm. A continuous wave output power up to 1.6 W was achieved using an intracavity diamond heat spreader. Intracavity birefringent filter was used to tune the wavelength of the device in 25 nm range.

Continuous wave optically pumped semiconductor disk lasers based on Stranski-Krastanow grown quantum dots reach 1270nm for first time with the output power up to 1.6 W. Samples with different numbers of QD layers are compared.

We report a disk laser using two quantum-dot semiconductor gain elements, resulting in what we believe is the first demonstration of intracavity frequency conversion with these active media. Output power of 6 W has been obtained in dual-gain configuration at a wavelength of 1180 nm, while single-gain lasers produced up to 3 and 4 W individually, limited by thermal rollover in the output characteristics. The gain enhancement achieved with two active elements comprising 39 layers of Stranski-Krastanov InGaAs quantum dots allows for intracavity frequency doubling delivering 2.5 W of orange radiation.

We demonstrate an optically pumped semiconductor disk laser using 39 layers of Stranski-Krastanov InGaAs quantum dots self-assembled during epitaxial growth on a monolithic GaAs/AlAs distributed Bragg reflector. The gain structure bonded to an intracavity diamond crystal heat spreader allows 1.75 W single-transverse-mode output (M(2)1.2) with circular beam shape operating at 1180 nm in a disk laser geometry.

We demonstrate a wafer fused mode-locked optically-pumped semiconductor disk laser operating at 1.3 µm spectral range. Both the gain mirror and the SESAM incorporate InP-based active region wafer fused with GaAs/AlGaAs distributed Bragg reflector.

In this letter, we demonstrate an optically pumped semiconductor disk laser frequency doubled with a periodically poled lithium tantalate crystal. Crystals with various lengths were tested for intracavity frequency conversion. The semiconductor disk laser exploited GaInNAs-based active region with GaAs-AlAs distributed Bragg mirror to produce emission at 1.2-μm wavelength. The frequency doubled power up to 760 mW at the wavelength of 610 nm was achieved with a 2-mm-long crystal.

We report two GaInNAs/GaAs semiconductor disk lasers emitting at the wavelengths of 1180 nm and 1220 nm. The lasers generated 5 W and 7 W output powers, respectively, at a mount temperature of 15° C. Both the gain mirrors were grown by molecular beam epitaxy and consisted of a GaAs/AlAs distributed Bragg reflector and an active region with 10 GaInNAs/GaNAs/GaAs QWs.

Novel 1310 nm and 1550 nm optically pumped VECSELs based on wafer fused InAlGaAs/InPAlGaAs/ GaAs gain mirrors demonstrate high CW fundamental mode continuous wave output in excess of 2 W at room temperature.

Visible laser light is needed for a number of applications including life science and laser projection displays. To produce red light from a semiconductor disk laser (SDL) via frequency doubling, laser should generate light around the wavelength of 1.2 µm. This spectral range is challenging with typically used InGaAs and GaAs structures due to an increased lattice mismatch between the two materials. We report a novel approach based on a wafer fused optically-pumped semiconductor disk laser operating at 1.2 µm. This technique allows integrating materials with different lattice constants and provides convenient means to extend the operation wavelength of an SDL [1].

There has been an increasing interest in compact coherent sources at 600 nm for a number of applications, e.g. orange-red components for laser projection displays [1], and excitation sources in photodynamic therapy [2]. The need for these sources become more apparent if one recalls that the amber-orange-red spectral region remains unreachable for conventional surface emitting diode lasers due to a lack of suitable direct bandgap materials providing sufficient carrier confinement in the quantum wells. One way forward is the frequency doubling of infrared light. Recently, a second-harmonic generation (SHG) at 610 nm with an output power of 2.7 W has been demonstrated from an optically-pumped semiconductor disk laser with a BBO crystal [3]. While nonlinear crystals such as BBO and LBO are highly resistant to optical damage inflicted by visible light, their effective non-linear coefficient, d eff is low (1–3 pm/V). Periodically poled lithium tantalate (LT) and lithium niobate crystals on the other hand offer d eff values above 10 pm/V. They are highly transparent from the UV to mid-IR spectral region. However, being photorefractive, these materials have traditionally been considered to be not suitable for intracavity generation of visible light. Recent advances in double-crucible Czochralski (DCZ) method made it possible to produce nearly stoichiometric LT materials (Mg:SLT) with increased resistance to optical damage [4].

Semiconductor disk lasers (SDLs) operating around 1.55 µm have been the subject of increasing interest. The performance of monolithically grown SDLs in this wavelength range suffers, however, from the poor quality of the InP-based distributed Bragg reflector (DBR). Recently, wafer fusion technique was applied to a long-wavelength SDL to avoid this obstacle [1]. An active region grown on InP substrate was wafer fused to a GaAs/AlGaAs-based DBR resulting in a device operating at 1.57 µm with 2.6 W average output power and a near diffraction limited beam. Here we present the first mode-locked SDL using a wafer-fused gain reflector.

A wafer fusing was applied to integrate an InP-based active medium and a GaAs/AlGaAs distributed Bragg reflector in an optically pumped semiconductor disk laser. Over 50 mW of output power at room temperature in 1570-1585 nm spectral range was demonstrated. The results of this study reveal an important finding: the wafer fusion can be used in emitters with high power. This approach would allow for monolithic integration of lattice-mismatched compounds, quantum-well and quantum-dot based media and promises substantial wavelength tailoring of semiconductor disk lasers.

We report a passively mode-locked optically pumped semiconductor disk laser with emission at 1220 nm. Both the gain and the semiconductor saturable absorber mirrors used to build the laser are based on InGaAsN/GaAs quantum wells fabricated by molecular beam epitaxy. The growth parameters have been optimized to reduce the detrimental effects of nitrogen on the emission efficiency. Using a gain mirror comprising ten GaInNAs quantum wells with a relatively low nitrogen content and a saturable absorber mirror incorporating two GaInNAs quantum wells, we demonstrate generation of pulses with durations of ∼5ps and average powers up to 275mW. We describe the fabrication procedure of the semiconductor structures and the results of laser characterization.

We report an essential progress towards the development of efficient GaInNAs-based semiconductor disk lasers operating at 1220 nm spectral range. The gain mirrors were fabricated by molecular beam epitaxy using a radio frequency plasma source for incorporating the nitrogen. The typical structure consisted of a 30-pair GaAs/AlAs distributed Bragg reflector and 10 GaInNAs quantum wells with relatively low content of nitrogen. The growth parameters and the composition of the structures have been optimized to reduce the detrimental effect of nitrogen on the emission efficiency. We have achieved a maximum output power of 3.5 W and a differential efficiency of 20%.

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 92, 101123 (2008) and may be found at https://doi.org/10.1063/1.2898165. An optically pumped semiconductor disk laser using submonolayer quantum dots (SML QDs) as gain medium is demonstrated. High-power operation is achieved with stacked InAs∕GaAs SML QDs grown by metal-organic vapor-phase epitaxy. Each SML-QD layer is formed from tenfold alternate depositions of nominally 0.5 ML InAs and 2.3 ML GaAs. Resonant periodic gain from a 13-fold nonuniform stack design of SML QDs allows to produce 1.4W cw at 1034nm. The disk laser demonstrates the promising potential of SML-QD structures combining properties of QD and quantum-well gain media for high-power applications.

Owing to their good beam quality and high output power, near-infrared semiconductor disk lasers provide an attractive opportunity for visible light generation via frequency conversion. The typical cavity arrangement of a semiconductor disk laser, consisting of a semiconductor multiple quantum well gain mirror and one or more external mirror, offers a convenient configuration for intracavity frequency doubling. Recent progress in the disk laser development has led to demonstrations of multi-watt green-blue-yellow sources. These achievements have been enabled by the possibility to integrate high performance InGaAs/GaAs gain media and Al(Ga)As/GaAs Bragg reflectors operating in the 940-1160 nm wavelength range. In order to achieve ~620 nm red emission, a laser emitting near the fundamental wavelength of 1240 nm is needed. To achieve this spectral range we have developed GaInNAs/GaAs gain mirrors and we have achieved 1 W of output power at 617 nm by frequency doubling in a BBO crystal. This is to our knowledge the highest power reported to date for intracavity doubled disk laser based on dilute nitride gain material.

Semiconductor disk laser with mode control using the feedback from a partially reflecting fiber Bragg grating. With seed signal, the wavelength is locked to the Bragg wavelength and beam quality factor M2 decreases from 1.6 to below 1.05.

We present new approaches for power scaling and tunability in semiconductor disk lasers. The novel concepts allow for reduced thermal load of the gain material, increasing the threshold of rollover and extending the capability for boosting the output power without significant degradation in the beam quality. The proposed technique for power scaling of optically-pumped semiconductor disk lasers is based on the multiple gain scheme. The method allows for significant power improvement while preserving good beam quality. Total power of over 8 W was achieved in dual-gain configuration, while one-gain lasers could produce separately about 4 W, limited by the thermal rollover of the output characteristics. The results show that reduced thermal load to a gain element in a dual-gain cavity allows extending the range of usable pump powers boosting the laser output. Tunable Sb-based semiconductor disk laser operating at 2-mm is demonstrated with nearly 100 nm operation range. The maximum output is 210 mW and the 3dB tuning range spans from 1946 to 1997 nm. The wavelength tuning is based on an intracavity birefringent filter. The potential of semiconductor disk lasers for high repetition rate ultrashort pulse generation using harmonic mode-locking is also discussed. We report on optically-pumped vertical-external-cavity surface-emitting lasers passively mode-locked with a semiconductor saturable-absorber mirror. The potential of harmonic mode-locking in producing pulse trains at multigigahertz repetition rates has been explored. The results present first systematic study of multiple pulse formation in passively mode-locked VECSELs.

We report on a 2085 nm holmium-doped silica fiber laser passively mode-locked by semiconductor saturable absorber mirror and carbon nanotube absorber. The laser, pumped by a 1.16 μm semiconductor disk laser, produces 890 femtosecond pulses with the average power of 46 mW and the repetition rate of 15.7 MHz.

A 1.6 mu m mode-locked Raman fiber laser pumped by a 1480 nm semiconductor disk laser is demonstrated. Watt-level core pumping of the single-mode fiber Raman lasers with low-noise disk lasers together with semiconductor saturable absorber mirror mode locking represents a highly practical solution for short-pulse operation. (C) 2010 Optical Society of America

24 students, who participated in a summer session mathematics enrichment program, viewed subliminally presented messages. Prior to each class, the experimental group of 16 viewed a subliminally presented psychoanalytic merging message and the control group of 8 viewed a neutral message. After 20 sessions students were retested. Experimental students had higher mathematics scores than controls. These data are compared with results obtained by other investigators.

We demonstrate multiwatt cw output power from an optically pumped quantum-dot semiconductor disk laser. Continuous-wave output power of 4.35 W with 22% slope efficiency was demonstrated at a center wavelength of 1,032 nm. This represents an increase in power of 15 times and an increase in slope efficiency of 10 times from the previously published results using Stranski-Krastanow grown quantum dots. An intracavity diamond heat spreader was used for thermal management. The maximum output power was limited by the available pump power, and no sign of thermal rollover was observed.

We report a wafer-fused high power optically-pumped semiconductor disk laser operating at 1.3 microm. An InP-based active medium was fused with a GaAs/AlGaAs distributed Bragg reflector, resulting in an integrated monolithic gain mirror. Over 2.7 W of output power, obtained at temperature of 15 degrees C, represents the best achievement reported to date for this type of lasers. The results reveal an essential advantage of the wafer fusing technique over both monolithically grown AlGaInAs/GaInAsP- and GaInNAs-based structures.

Intracavity frequency doubling of an optically pumped GaInNAs semiconductor disk laser by a periodically poled near-stoichiometric lithium tantalate crystal has been investigated. Stable second-harmonic generation at 610 nm has been achieved with an output power of 730 mW, limited only by the spectral acceptance range and Fresnel losses of the crystal. Spectral tuning of 8 nm was realised with a Fabry-Perot etalon.

We report a wafer fused high power optically pumped semiconductor disk laser incorporating InP-based active medium fused to a GaAs/AlGaAs distributed Bragg reflector. A record value of over 2.6 W of output power in a spectral range around 1.57 microm was demonstrated, revealing the essential advantage of the wafer fusing technique over monolithically-grown all-InP-based structures. The presented approach allows for integration of lattice-mismatched compounds, quantum-well and quantum-dot based media. This would provide convenient means for extending the wavelength range of semiconductor disk lasers.

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 93, 051104 (2008) and may be found at https://doi.org/10.1063/1.2968137. We demonstrate temperature-independent output characteristics of an optically pumped semiconductor disk laser (SDL) based on quantum dots (QDs) grown in the Stranski-Krastanow regime. The gain structure consists of a stack of 7×3 QD layers, each threefold group being located at an optical antinode position. The SDL emits at 1210nm independent of the pump power density. Threshold and differential efficiency do not dependent on heat sink temperature. Continuous-wave operation close to 300mW output power is achieved using the ground-state transition of the InGaAs QDs.

Quantum dots grown by metal organic vapour phase epitaxy in the Stranski-Krastanow regime are succesfully implemented for the first time as active media in optically pumped vertical external cavity surface emitting lasers. To optimise the gain the quantum dots are engineered to match the excited state luminescence to the cavity resonance. Room temperature continuous-wave operation at 1040 nm wavelength is demonstrated. An output power of 280 mW is achieved, limited only by the onset of thermal rollover. The differential conversion efficiency is 6.7%.

We report on a high-power GaInNAs/GaAs optically pumped semiconductor disk laser operating at a wavelength of 1240 nm. The laser structure consisted of 12 dilute nitride (GaInNAs) quantum wells placed on top of a GaAs/AlAs distributed Bragg reflector, the whole structure being grown by molecular beam epitaxy. A diamond heat spreader was bonded onto the sample for improved heat dissipation. When cooled down to 8°C, the laser produced continuous-wave output power up to 1.46 W in the TEM00 mode, demonstrating the potential of dilute nitrides for high-power disk laser applications.

We report on a GaInNAs/GaAs semiconductor disk laser frequency-doubled to produce orange-red radiation. The disk laser operates at a fundamental wavelength of 1224 nm and delivers an output power of 2.68 W in the visible region with an optical-to-optical conversion efficiency of 7.4 %. The frequency-converted signal could be launched into a single-mode optical fiber with 70–78 % coupling efficiency, demonstrating good beam quality for the visible radiation. Using a Fabry-Perot glass etalon the emission wavelength could be tuned over an 8 nm spectral range.

A 1234 nm GalnNAs/GaAs optically-pumped semiconductor disk laser utilising an intracavity BBO (beta barium borate) crystal for nonlinear frequency conversion is reported. 1 W of power at 617 nm has been achieved.

We report on an optically-pumped intracavity frequency doubled GaInNAs/GaAs -based semiconductor disk laser emitting around 615 nm. The laser operates at fundamental wavelength of 1230 nm and incorporates a BBO crystal for light conversion to the red wavelength. Maximum output power of 172 mW at 615 nm was achieved from a single output. Combined power from two outputs was 320 mW. The wavelength of visible emission could be tuned by 4.5 nm using a thin glass etalon inside the cavity.