Cr4+:YAG crystals Chromium Doped Yttrium AIuminum Garnet

Co2+:MgAl2O4 Cospinel is a relatively new material for passive Q-switching in lasers emitting from 1.2 to 1.6 μm, in particular, for eye-safe 1.54 μm Er:glass laser, but also works at 1.44 μm and 1.34 μm wavelengths. Spinel is a hard, stable crystal that polishes well. Cobalt substitutes readily for magnesium in the Spinel host without the need for additional charge compensation ions. High absorption cross section (3.5×10-19 cm2) permits Q-switching of Er:glass laser without intracavity focusing both with flash-lamp and diode-laser pumping. Negligible excited-state absorption results in high contrast of Q-switch, i.e. the ratio of initial (small signal) to saturated absorption is higher than 10.

HGO grows Nd:YLF laser crystals using Czochralski technology. Nd3+:YLF crystal is characterized by its long lifetime of 4F3/2 neodymium energy level. Compared to Nd:YAG, the lower thermal conductivity and a weak negative dn/dT lead to lower thermal distortions and allow to achieve a better output beam quality. Another distinctive feature is the high UV transparency, which is favorable for pumping with xenon flash lamps.

Germanium (Ge) is the preferred lens and window material for high performance infrared imaging systems in the 8–12 um wavelength band.

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.

Plano-convex circular cylindrical lenses are useful for line imaging or uni-axial magnification in a wide range of applications. These lenses may be combined with other lenses to form complex imaging systems.

Achromatic Lenses are used to minimize or eliminate chromatic aberration. The achromatic design also helps minimize spherical aberrations. Achromatic Lenses are ideal for a range of applications, including fluorescence microscopy, image relay, inspection, or spectroscopy. Achromatic Lenses, which are often designed by either cementing two elements together or mounting the two elements in a housing, create smaller spot sizes than comparable singlet lenses.

Sapphire window retains its high strength at high temperatures, has good thermal properties and excellent transparency. It is chemically resistant to common acids and alkali at temperatures up to 1000 °C as well as to HF below 300 °C. These properties encourage its wide use in hostile environments where optical transmission in the range from the vacuum ultraviolet to the near infrared is required.

Magnesium Fluoride Windows applicable for wide range spectrum, transmits well into the VUV region at the hydrogen Lyman-alpha line and beyond and it is particularly useful for Excimer laser application.It is resistant to mechanical and thermal shock, to radiation, and is chemically stable.