Catalog

ICL celebrated its 50th anniversary in 2012. We have produced quality crystal optics for spectroscopy and CO2 lasers since 1962. ICL operates a vertically integrated crystal optics production plant. We grow our own crystals and we are the only U.S. producer of KBr crystals. We welcome the opportunity to quote on custom sized optics, coated optics, crystal and other optical materials not listed and optical assemblies such as beam splitters. We can produce optics from crystal materials such as CdMnTe, CdMnHgTe, CdTe, Si, LiF, CsBr, AgBr, MgF2 as well as from glass and composition materials such as polyethylene, BK-7 and AMTIR.

ICL celebrated its 50th anniversary in 2012. We have produced quality crystal optics for spectroscopy and CO2 lasers since 1962. ICL operates a vertically integrated crystal optics production plant. We grow our own crystals and we are the only U.S. producer of KBr crystals. We welcome the opportunity to quote on custom sized optics, coated optics, crystal and other optical materials not listed and optical assemblies such as beam splitters. We can produce optics from crystal materials such as CdMnTe, CdMnHgTe, CdTe, Si, LiF, CsBr, AgBr, MgF2 as well as from glass and composition materials such as polyethylene, BK-7 and AMTIR.

Unpolished crystal optics are also known as blanks. These windows are finely ground with flat parallel surfaces. As sold they are opaque. They can be water polished quickly to achieve 90% transmission. The transmission of water polished KBr, KCI and NaCl will be the same as Real Crystal® IR Cards.These blanks can also be polished to precision optics. Blanks are ideal for mulls, smears and qualitative testing.

Quantity discounts and custom sizes are available. Ask for a quotation.

Keep your powder dry! And clean. Grind your own from random cuttings of ICL’s own pure crystal boules. We provide only the cleanest and highest transmission materials, free from spurious absorption bands.

Alkali Halide crystals (KBr, KCI and NaCl) are cubic in structure. They can be cleaved to relatively precise shapes. Applications range from teaching aids to electronics to crystal blanks for polished optics.

Polyethylene is a useful transmission material for far infrared sampling.  Polyethylene is non-absorbing beyond 14 microns.  Transmission is about 80%.

ICL provides inexpensive  KBr  cover slips for samples heated in highly  pressurized chambers by  CO₂ lasers to liberate entrapped  gases such as Argon from  minerals and other natural samples for 40Ar-39Ar dating using a mass spectrometer.    KBr is the material of choice for this application since  KCl and NaCl tend to release chlorine which can damage an expensive mass spectrometer.   Common choices for this application are our 41 x 3mm KBr cover slip windows Part No. 0002C-9343.  Other sizes are available; inquire for pricing.

High refractive index material such as ZnSe creates fringing, which is also known as channeling. Fringes are useful for path length calibration, but fringes can also interfere with spectral analysis, particularly when the refractive index of the sample is not well matched to the refractive index of the sample. Fringing can occur in a single window where the light is reflected between parallel surfaces of window and in a cell containing a pair of windows where the light is reflected off of both windows. The smaller the path length, the more dramatic the fringing effect is. Accordingly, thinner windows will have more dramatic fringes than thicker windows. Fig. 1 shows the fringe pattern of a properly assembled ZnSe 0.1mm path length liquid cell. This cell can be calibrated to a high degree of accuracy and has utility for well matched samples. But, if the sample is not well matched and ZnSe or some other high index material is chosen for reasons such as spectral range or material compatibility, then the spectroscopist may be well advised to consider means useful to limit fringing.

A simple way to limit fringing is to wedge the spacers in liquid cells. The downside is that the path length cannot be calibrated with the same high degree of accuracy that would otherwise be possible. This method works because the wedged spacer insures the windows are not parallel. There is an additional charge for the wedged spacer and the part number is 0001-9228.

Another simple way to limit fringes is to fog the windows. This of course only works with deliquescent windows which typically have a low refractive index anyway. Most windows that comprise the sample compartment seal in FTIR spectrophotometers are wedged KBr with a moisture barrier coating.

In gas cells, we provide windows that are both wedged and anti-reflective (AR) coated on one side. Prices for stock AR/wedged windows are shown below.

Broadband AR coatings also can be applied on both sides of a window, and are typically designated as AR/AR. Although AR coatings do have some spurious bands, they can generally be tolerated and can be compensated by means of a background scan of the sampling accessory containing the AR coated windows.

We routinely provide wedged windows in many materials. Wedged windows are the traditional and most inexpensive means of limiting fringing.