Diffusion Bonded Crystals with High Damage Threshold

Nd:YAG is the earliest and most famous laser host crystal. Since it combines great advantages in many basic properties,Nd:YAG is the ubiquitous presence for near-infrared solid-state lasers and their frequency-doubler, tripler, and higher order multiplier. It is widely used in industrial, medical, military and scientific fields.. Nd:YAG crystals are wildly used in all types of solid-state laser systems-frequency-doubled continuous wave, high-energy Q-switched, and so forth.Its good fluorescent lifetime thermal conductivity and physical strengths makes it suitable for high power lamp pumped laser.

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.

Silicon is used as an optical window primarily in the 3 to 5 micron band and as a subsrate for production of optical filters and windows.     Silicon (Si) is grown by Czochralski pulling techniques (CZ) and contains some oxygen that causes an absorption band at 9 microns. To avoid this, material can be prepared by a Float-Zone (FZ) process. Optical silicon is generally lightly doped (5 to 40 ohm cm) for best transmission above 10 microns, and doping is usually boron (P-type) and phosphorus (N-type). After doping silicon has a further pass band: 30 to 100 microns which is effective only in very high resistivity uncompensated material.    

Nd:GdVO4, is a promising material for diode pumped lasers. Similar to the more well-known Nd:YVO4 crystal, Nd:GdVO4 crystal also exhibits high gain, low threshold, and high absorption coefficients at pumping wavelengths. Nd:GdVO4 has the additional advantage over Nd:YVO4 of a much higher thermal conductivity. For CW lasing at 1.06 um and 1.34 um and intracavity doubling with KTP and LBO, the gadolinium vanadate have produced a higher slope efficiency or optical conversion than Nd:YVO4.

Non-Polarizing Cube Beamsplitters also called NPBS Cube is a more sophisticated type consisting of two right- angle prisms cemented together at their hypotenuse faces.The cemented face of one prism is coated. Before cementing, with a metallic or dielectric layer having the desired reflecting properties, both in the percentage of reflection and the desired color. The absorption loss to the coating is minimal and transmission and reflection could be designed to 10%, 20%, 30%, 40%, 50%, etc.

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.

A cylindrical lens is a lens that focuses light on a line instead of a point, like a spherical lens. The curved face or faces of a cylindrical lens are sections of a cylinder, and focus the image passing through it into a line parallel to the intersection of the surface of the lens and a plane tangent to it. The lens compresses the image in the direction perpendicular to this line and leaves it unaltered in the direction parallel to it (in the tangent plane). In a light sheet microscope, a cylindrical lens is placed in front of the illumination objective to create the light sheet used for imaging. Cylindrical lenses focus or expand light in one axis only. They can be used to focus light into a thin line in optical metrology, laser scanning, spectroscopic, laser diode, acousto-optic, and optical processor applications. They can also be used to expand the output of a laser diode into a symmetrical beam. Cylindrical lenses are widely used in telecom applications like WSS, 40G/100G modules and laser applications like pump laser modules