Crystals and optics processing services

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.

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.

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.

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.

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

Double Convex Lenses are used in image relay applications, or for imaging objects at close conjugates. Double Convex Lenses have positive focal lengths, along with two convex surfaces with equal radii. Aberrations will increase as the conjugate ratios increase.  Double-Convex Lenses are used in a range of industries or applications. HG OPTRONICS offers Double Convex lenses with a variety of coating options.

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.    

A band pass filter is a device that passes frequencies within a certain range and rejects (attenuates) frequencies outside that range, and it’s used to selectively transmit a portion of the spectrum while rejecting all other wavelengths.