Waveplate

HGO grows LiF crystals in house using Czochralski technology. LiF crystal or lithium fluoride crystal is an optical material with outstanding transmittance in VUV region. It is also used for windows, prisms, and lenses in the visible and infrared in 0.104µm-7µm. LiF single crystal is sensitive to thermal shock and would be attacked by atmospheric moisture at 400°C. When working at a high temperature of 600°C, the LiF crystal softens and is slightly plastic, so it can be bent into radius plates. In addition irradiation produces color centers. Hence, users should take measures to protect LiF crystals from moisture and high energy radiation damages. What is more LiF can be cleaved along (100) plane and less commonly (110) plane. The optical characteristics are good and yet the structure is not perfect and cleavage is difficult.

HGO grows Tm:YLF laser crystals using Czochralski technology. Tm:YLF is an important middle infrared laser crystal. Because Tm:YLF is negative uniaxial crystal, whose thermal refractive index coefficient is negative, some thermal distortion may be counteracted and high-quality light can be output. Conveniently pumped at 792nm, 1.9μm linearly polarized beam is output in a axis, and non-linearly polarized beam is output in c axis. The YLF crystals has low non-linear refraction index value and thermo optical constants, which makes these crystals applicable in research, development, education, production, photonics, optic, laser technology and telecommunications. Besides, Tm3+:YLF lasers are ideal pump sources for 2.1 μm Ho3+:YAG lasers. This is due to a good overlap of Tm3+:YLF emission and Ho3+:YAG absorption spectra and the capacity of producing linearly polarized output. What is more, the refractive index of Tm3+:YLF decreases with temperature, leading to a negative thermal lens that is partly compensated by a positive lens effect due to end face bulging.

Fused silica window, with low thermal expansion,  providing stability and resistance to thermal shock over large temperature excursions, wide thermal operating range and high laser damage threshold, is a better choice for transmission from UV to IR.

Laser Protect Windows(Laser protective glass, protective filters or welding protective windows) are used to save for the high cost of laser optics.

α-BBO (α-BaB2O4) is a negative uniaxial crystal which has large birefringence over a broad transparent range of 190nm to 3500nm. α-BBO is an excellent crystal especially in UV and high power applications. The physical, chemical, thermal, and optical properties of alpha-BBO crystal are similar to those of Beta-BBO. However, there is no second order nonlinear effect in alpha-BBO crystal due to the centrosymmetry in its crystal structure and thus it has no use for second order nonlinear optical processes. Instead, alpha-BBO is widely used for fabrication of polarizers, polarizing beam displacers, phase retarders, birefringent plates, and time delay compensators especially those for UV and high power lasers.

HG Optronics.,INC. can provide Metal Coated Mirror，Dielectric Coated Mirror and Dichroic Mirror which are made of substrate such as BK7, Optical glass, Fused Silica, CaF2 and so on.  

Potassium Gadolinium Tungstate (KGd(WO₄)₂) crystal is an excellent stimulated Raman laser crystal with characteristics such as a wide light transmission range, good thermal conductivity, high damage threshold, large Raman shift coefficient, and high Raman gain. It can maintain high conversion efficiency and beam quality during the Raman frequency conversion process. The KGW crystal can withstand high pump power and is suitable for pump lights of various wavelengths, making it widely used in Raman lasers, laser frequency conversion, medical imaging, photodynamic therapy, environmental monitoring, spectroscopy research, material processing, and other fields.

Longpass filters are ideal for a variety of applications, such as gas monitoring, temperature, sensing, thermal imaging and motion sensing, etc. Longpass filters block shorter wavelengths and transmit longer wavelengths. Blocking can be from reflectance, absorption or a combination. Transmission in the pass band can be enhanced with an antireflection coating on the second surface.