A multi-wavelength mid-infrared laser based on a multi-period doped MgO periodically poled lithium niobate (MgO:PPLN) was reported in this letter. The pump source was 1.064μm Q-switched Nd:YVO<sub>4</sub> laser with a pulse repetition rate of 15kHz and pulse duration around 30ns. Three domain periods of 28.5μm, 29μm and 29.5μm in series were fabricated in a 2mm-thick z-cut MgO:PPLN, and the length of each domain period was 20mm. The extra-cavity singly resonant optical parametric oscillator had been demonstrated with a compact two-mirror cavity. Three idler wavelengths of 3825nm, 4004nm and 4165nm in the mid infrared were obtained at the same time, and the total output power was 139mW at 1.064μm pump power of 3.09W corresponding to optical-to-optical conversion efficiency of 4.5％ and the pump threshold was 1.04W for the 60mm-long MgO:PPLN.
Compact and efficient blue laser sheet has important applications in the field of measurement, with laser diode end pumped Nd:YAG directly and LBO intracavity frequency doubling, a compact and efficient CW 473nm blue laser sheet composed of dual path liner blue laser is realized. At an incident pump power of 12.4W, up to 1.4W output power of the compound blue laser is achieved, the optical-to-optical conversion efficiency is as high as 11.3%.
Compact, high power, and low-cost green laser light sources are needed in projection-related applications such as digital cinema, rear-projection television, simulators, and command and control stations. We report a LD array directly pumped intracavity SHG Nd:YVO<sub>4</sub>/PPMgLN laser without lens or waveguide in this letter. A compact 3.12 W green laser was demonstrated by intra-cavity frequency doubled using a PPMgLN bulk crystal by a 19-emitter LD array pumped(single bar), the conversion efficiency from input LD array was 9.2%. A line-beam output suitable for laser projectors was generated, which has the potential to be scalable to small volumes and low costs for laser projection displays.
With diode end pumped Nd:YAG directly and LBO intracavity frequency doubling, a compact, high efficient continuous wave blue laser at 473nm is realized. When the incident pump power reach 6.2W, 630mW maximum output power of blue laser at 473nm is achieved with 15mm long LBO, the optical-to-optical conversion efficiency is as high as 10.2%.
With diode end pumped Nd:YVO<sub>4</sub> and PPMgLN intracavity sum-frequency mixing, a compact, high efficient continuous wave yellow laser at 593.5nm is realized. At an incident pump power of 5.7W, up to 620 mW output power of yellow laser is achieved, the optical-to-optical conversion efficiency is as high as 10.9%.
We described a widely tunable intracavity continuous-wave singly resonant optical parametric oscillator (SRO) through a minimal laser diode end-pumped Nd:YVO<sub>4</sub> laser. Laser source from 1.9μm to 2.4μm is obtained by temperature tuning of the 32.2μm period periodically poled MgO:LiNbO<sub>3</sub>(PPMgLN) crystal. The maximum power, 0.84W signal wave at 1.966μm and 0.56W idler wave at 2.319μm, are simultaneously obtained at 5.5 W of input diode power. The corresponding conversion efficiency are 15.2% and 10.2% respectively, so the whole efficiency is more than 25%. This allows the development of practical infrared cw SRO’s using compact, widely available, low-cost laser pump sources.
High efficient and compact continuous-wave arrayed green laser is demonstrated based on periodically poled MgO:LiNbO<sub>3</sub>(PPMgLN), with a pump power of 16.5 W (5.5 W×3) at 808 nm, 7.36W output power of 3-arrayed green beams at 532 nm is achieved with a high optical-to-optical conversion efficiency of 44.6%.
High power green laser has many applications such as high brightness laser projection and large screen laser theater. A compact and high power green-light source has been developed in diode-pumped solid-state laser based on MgO doped periodically poled LiNbO<sub>3</sub> (MgO:PPLN). 5W fiber coupled green laser is achieved by dual path Nd:YVO<sub>4</sub>/MgO:PPLN intra-cacity frequency-doubled. Single green laser maximum power 2.8W at 532nm is obtained by a 5.5W LD pumped, MgO:PPLN dimensions is 5mm(width)×1mm(thickness)×2mm(length), and the optical to optical conversion efficiency is 51%. The second LD series connected with the one LD, the second path green laser is obtained using the same method.
Then the second path light overlap with the first path by the reflection mirrors, then couple into the fiber with a focus mirror. Dual of LD, Nd:YVO<sub>4</sub>, MgO:PPLN are placed on the same heat sink using a TEC cooling, the operating temperature bandwidth is about 12°C and the stablity is 5% in 96h. A 50×50×17mm<sup>3</sup> laser module which generated continuous-wave 5 W green light with high efficiency and width temperature range is demonstrated.