Crystals and optics processing services

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

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.

Ytterbium-doped Potassium Gadolinium Tungstate (Yb:KGd(WO₄)₂, Yb:KGW) crystal is an excellent laser gain material, boasting numerous advantages over the widely used Nd³⁺-doped materials. Its wide spectral emission band of 1023-1060 nm enables the generation of short laser pulses (picosecond or femtosecond level). The broad absorption band at 980 nm and highly absorbent pump radiation allow it to efficiently utilize diode laser pumping. Compared with YAG doped with Yb³⁺ ions, KGW crystal has a larger absorption cross-section, which reduces the minimum pump intensity required to achieve transparency in the quasi-two-level system of Yb.

Polarization Beamsplitter Cubes are constructed by cemented two right angle prisms, the hypotenuse of one prism is coated with polarization dielectric coating. When used with normal incident, un-polarized light, the incident beam is separated into two polarized beams, p-polarized component is passed straight through, s-polarized component is reflected out at 90deg.

The Anamorphic prisms are used in pairs to magnify input beam size along one axis while leaving the other axis unchanged. The elliptical laser diode beams can be transferred into nearly circular.

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 Concave Lenses are ideal for beam expansion, light projection, or for expanding an optical system's focal length. Plano Concave Lenses, which have one concave surface, are Optical Lenses with negative focal lengths. Plano-Concave Lenses should be shaped with the plano, or flat, surface towards the desired focal plane.Plano-Concave Lenses are ideal for use in a range of applications or industries. HG OPTRONICS offers Plano-Concave lenses with a variety of coating options.

Invented by H.W. Dove, Dove Prisms are also known Reversion prisms.  When the prism is rotated about its length axis, the image viewed through the prism rotates at twice the prism rotation rate.  This is an unusual and sometimes useful property for special applications. Entry and exit faces are anti-reflection coated.