Crystals and optics processing services

Cr4+:YAG (Y3Al5O12) crystal is ideal for passive Q-switch operation of Nd:YAG and other Nd3+ or Yb3+ doped laser crystals in the wavelength range of 900 nm to 1200 nm. Passive Q-switches or saturable absorbers provide high power laser pulses without electro-optic Q-switches, thereby reducing the package size and eliminating a high voltage power supply. A remarkable feature of Cr4+:YAG is the high damage threshold of >10 J/cm2@1064 nm, 10 ns. Its absorption band extends from 900 nm to 1200 nm and peaks around 1060 nm with a very large absorption cross-section.

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.

BK7 window is the most common type of window. It has good performance over visible and near infrared wavelength regions. At the same time, BK7 window is ideal for applications require minimal transmitted beam deviation. It is suitable for AR coating.

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.    

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.

The Positive Meniscus Lenses are a convex-concave lens, but it is thicker at the center than at the edges. They are felt polished and are used universally in the ophthalmic industry where convention dictates that lens power be specified in Diopters. The Negative Meniscus Lenses are a convex-concave lens, but it is thinner at the center than at the edges. Otherwise description is similar to Plano Concave lenses.  

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.

Calcium Fluoride windows and lenses for UV and IR spectrum. Custom made CaF2 windows, CaF2 lenses and wedges according to customer's specifications. CaF2 windows up to 220mm diameter; CaF2 wedges, prisms and CaF2 mirrors; Excimer CaF2 optics, Raman grade CaF2 optics and etc.