Potassium Dihydrogen Phosphate (KDP) and Potassium Deuterium Phosphate (KD*P) are among the most widely-used commercial NLO materials. They are commonly used for doubling, tripling and quadrupling of Nd:YAG laser at the room temperature. In addition, they are also excellent electro-optic crystals with high electro-optic coefficients, widely used as electro- optical modulators, Q-switches, and Pockels Cells, etc.

In the nonlinear optical crystal, BBO crystal is a kind of crystal with obvious comprehensive advantages and good performance. It has a very wide light transmission range, a large matching angle, a high resistance to light damage threshold, and a broadband temperature matching. Excellent optical uniformity, especially for the triple frequency of Nd:YAG lasers.

Lithium Triborate (LiB3O5 or LBO) is an excellent nonlinear optical crystal. LBO crystal and its NLO devices now are produced, manufactured and marketed by CRYSTRONG.

Lithium niobate (LiNbO3) crystals are widely used as doubling of wavelengths above 1000 nm and optical parametric amplification of 1064 nm pump light, and can also be used for quasi-phase matching. At the same time, lithium niobate crystals are also widely used in photoelectric regulators and waveguide materials, and as sapphire laser Q switches of Nd:YAG, Nd:YLF and Ti doping. Our company can provide high quality, large size lithium niobate crystals of various specifications for the above purposes.

Lithium iodate single crystal is a kind of nonlinear crystal with early industrial application. It has large nonlinear coefficient, radiation damage resistance and wide light transmission range. It can be used as a medium for generating second harmonic and parametric oscillation in laser technology. It can be used as a second, triple frequency and mixing frequency for medium and low power lasers. It can also be used to manufacture narrow pulse and wideband ultrasonic transducers with broad application prospects in the aerospace, chamical, metallurgical and petroleum industries.

Periodically poled lithium niobate (PPLN) is a highly efficient crystal for nonlinear wavelength conversion processes, which has a wide light transmission range and covers the NIR and MIR spectral regions, PPLN is used for SHG、SFG、OPO, and other nonlinear processes from Visible to MIR. In order to meet the requirements of modern optics for diverse laser wavelengths. the output of any wavelength in the transmittance range can be realized through the design of periodic structure.

​DLATGS crystal is a crystalline material with a pyroelectric effect, which can provide a wide range of infrared radiation from the near ultraviolet (NUV) light edge of 0.4 μm (~750 THz) to the far-infrared spectrum of 200 μm (~1.5 THz). It has a wide range of uses in aerospace, military, medical, and fire safety fields.

Zinc Germanium Phosphide crystal is an efficient mid-infrared nonlinear optical crystal material. Its transparency range is from 0.76 to 12.0 µm, making it suitable for applications in the mid-infrared spectral region such as optical parametric amplifiers (OPA), optical parametric oscillators (OPO), second-harmonic generation (SHG), and fourth-harmonic generation (FHG).

Rubidium Titanyl Phosphate (RbTiOPO4 or RTP) is an isomorph of KTP crystal which is used in nonlinear and Electro-Optical applications. It has advantages of high damage threshold (about 1.8 times of KTP), high resistivity, high repetition rate, no hygroscopy and no induced piezo-electric effect with electrical signals up to 60 kHz. Its transmission range is 350 nm to 4500 nm.

​Bismuth Triborate (BiB3O6 or BIBO) is a newly developed nonlinear optical crystal. It possesses large effective nonlinear coefficient, high damage threshold and inertness with respect to moisture. Its nonlinear coefficient is 3.5-4 times higher than that of LBO, 1.5-2 times higher than that of BBO. It is a promising doubling crystal to produce blue laser. The top-seeded solution growth (TSSG) technique is used at CRYSTRONG for the growth of BIBO single crystals.

​Potassium titanyl phosphate is widely used in commercial and military lasers, including laboratory and medical systems, range detectors, lidars, optical communications and industrial laser systems.
KTP is most commonly used for frequency-doubled Nd:YAG and other Nd-doped lasers, especially in low to medium power lasers. So far, the use of KTP for intracavity and extra cavity frequency doubling of Nd-doped lasers has gradually replaced visible-light dye lasers and tunable sapphire lasers. In many industrial studies, this type of laser is widely used as a green light source.

​Potassium Titanyl Arsenate (KTIOAsO4), or KTA, is a nonlinear optical crystal for Optical Parametric Oscillation (OPO) application.
It has good nonlinear optical and electro-optical properties, e.g. significantly reduced absorption in band range of 2.0-5.0 um, broad angular and temperature bandwidth, low dielectric constants.

is the laser crystal with the best comprehensive performance and the most important application, widely used in industrial, medical, military, and scientific research fields. It has high gain, low threshold, high efficiency, high optical quality, low loss, high mechanical strength, excellent thermal conductivity and thermal shock resistance. It is suitable for various laser operating modes (continuous, pulse, Q-switching, mode locking, frequency doubling, etc.) and high average power solid-state lasers.

Neodymium Doped Yttrium Orthovanadate (Nd:YVO4) is the most efficient laser host crystal for diode pumping among the current commercial laser crystals, especially, for low to middle power density. This is mainly for its absorption and emission features surpassing Nd:YAG. Pumped by laser diodes, Nd:YVO4 crystal has been incorporated with high NLO coefficient crystals (LBO, BBO, or KTP) to frequency-shift the output from the near infrared to green, blue, or even UV. This incorporation to construct all solid state lasers is an ideal laser tool that can cover the most widespread applications of lasers, including machining, material processing, spectroscopy, wafer inspection, light displays, medical diagnostics, laser printing, and data storage, etc. It has been shown that Nd:YVO4 based diode pumped solid state lasers are rapidly occupying the markets traditionally dominated by water-cooled ion lasers and lamp-pumped lasers, especially when compact design and single-longitudinal-mode output are required.

Erbium Doped Yttrium Aluminum Garnet (Er:YAG) is an excellent laser crystal which leases at 2940 nm. This band is at the hydroxyl absorption peak which can be strongly absorbed by biological tissues. So, it widely applies to medical area, such as dental (hard tissues), orthopedics, etc.

Ytterbium Doped Yttrium Aluminum Garnet (Yb:Y3Al5O12, Yb:YAG) is one of the most promising laser-active materials and more suitable for diode-pumping than the traditional Nd-doped systems. Compared with the commonly used Nd:YAG crystal, Yb:YAG crystal has a much larger absorption bandwidth to reduce thermal management requirements for diode lasers, a longer upper-laser level lifetime, three to four times lower thermal loading per unit pump power. Yb:YAG crystal at 1030 nm is a good substitute for a Nd: YAG crystal at 1064 nm and its second harmonic at 515 nm may replace Ar-ion laser (with a large volume), which emit at 514 nm.

​Titanium Doped Sapphire (Ti:Sapphire) is the most widely used laser crystal for widely tunable and ultrashort pulsed lasers with high gain and power outputs. CRYSTRONG possesses the advanced growth method of Temperature Gradient Technique (TGT), and it supplies large-sized (Dia. 30×30 mm3) Ti:Sapphire crystal in high quality free of light scatter, with the dislocation density less than 102 cm-2. The TGT grown sapphire crystal is characterized by the [0001] oriented growth, high doping level (α490 = 4.0 cm-1), high gain and laser damage threshold.

Due to its high damage threshold and high conversion efficiency, the HgGa₂S₄ (HGS) nonlinear crystal is particularly suitable for frequency doubling in the 1-10 μm range, as well as for OPO/OPA applications. For a 4 mm long HgGa₂S₄ element, the frequency doubling efficiency for CO₂ laser radiation is approximately 10% (pulse duration of 30 ns, radiation power density of 60 MW/cm²). Although growing large HGS crystals is quite challenging, their high conversion efficiency and broad radiation wavelength tuning range make them a promising competitor to AgGaS₂, AgGaSe₂, ZnGeP₂, and GaSe crystals.

Lithium Thioindate (LiInS2 or LIS) is an AIBIIIC2VI ternary semiconductor crystallizing with mm2 symmetry.
LiInS2 has a large nonlinear optical (NLO) coefficient, the non-linear characteristics of the crystals are close to AgGaS2 and AgGaSe2, but their crystal structures are different. LiInS2 crustal has a high laser damage threshold, and a wide transparent wavelength range, the useful transparency range of LiInS2 is 0.5–8 μm, which makes it an excellent mid-infrared NLO crystal. LiInS2 is pyroelectric as well, its electro-optical parameters are the base for using it as an effective electro-optical material. Three‐frequency collinear phase matching is possible in LiInS2, LiInS2 has large birefringence and low absorption in the THz frequency region is judged to be a potentially more useful optical nonlinear material than the analogous compound LiGaO2.

CrZnS and CrZnSe laser crystals typically do not exhibit excited-state absorption or upconversion. They possess an extremely broad absorption band, a large emission cross-section, excellent fluorescence quantum efficiency at room temperature, an ultra-wide emission bandwidth, as well as good chemical and mechanical properties. These characteristics make CrZnS & CrZnSe laser crystals excellent sources for efficient and powerful tunable mid-infrared lasers. Since the mid-infrared region corresponds to the atmospheric window, CrZnS & CrZnSe laser crystals hold significant potential for applications in optical communication, pollution gas detection, industrial combustion product testing, and other fields.

Silver Gallium Sulfide (AGS)
AgGaS2(AGS) crystal is one of the most effective nonlinear laser crystals used in the infrared working band at present. Because of its large nonlinear coefficient, high infrared transmittance, low optical absorption and scattering, and low wavefront distortion performance, its application in the infrared field has been popularized more and more. At present, this kind of crystal is the best choice for the frequency doubling material of CO2 laser with 10.6μm output.

Silver Gallium Selenide (AGSe)
AgGaSe2 silver selenide crystal, referred to as AGSe crystal for short, is one of the most effective crystal materials for frequency doubling of mid-infrared laser, and it also has excellent performance of three-wave nonlinear interaction (OPO). The useful light transmission range of AGSe crystal is 0.9-16μm, and it has wide phase matching ability. With the mature laser pumping, the OPO of AGSe crystal shows wide infrared tunable performance. Pumping AgGaSe2 crystal with Ho:YLF 2.05μm to obtain 2.5-12μm OPO tuned light source; Non-critical phase matching OPO pumped by 1.4-1.55 μm tuning light source outputs 1.9-5.5 μm tuning light source; Frequency doubling of pulsed CO2 laser.

Barium Gallium Selenide (BGSe)
BaGa4Se7 (BGSe for short) has large band gap (2.64eV), wide light transmission range (0.47~18μm), large nonlinear effect (d11=24.3 pm/V, d13=20.4 pm/V) and moderate birefringence （Δn=0.06@2μm）. BGSe crystal has good growth performance, and it is easy to obtain large-size and high-quality single crystals, which is suitable for high power output. BGSe crystal can be pumped by 1~3μm laser, and the highest tunable laser can reach 18 μm.

Selenium Germanium Gallium Barium (BGGSe)
BaGa2GeSe6 (BGGSe crystal for short) belongs to R3 space group of tripartite system, which has high laser damage threshold, wide transmission range (0.5~18μm), moderate birefringence, large nonlinear coefficient, stable chemical properties, high crystal symmetry and easy processing. Nd:YAG laser can be used for pumping, and it has important application potential in frequency conversion of infrared lasers such as frequency doubling of CO and CO2 lasers and generation of mid-far infrared lasers by optical parametric oscillation. Because of its low dispersion and high damage threshold, BGGSe crystal has advantages in ultra-wide mixing and ultra-short pulse output.

Ammonium Dihydrogen Phosphate is a member of the KDP-type crystal family and has been used in practical production for a long time as a large-sized crystal. Due to its various special functionalities like laser frequency doubling, electro-optic effect, and piezoelectric effect, the research and application of ADP crystals have been of significant interest to people.