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Caesium Iodide

Caesium Iodide (Csl) is a water soluble material that transmits from Ultra Violet (0.25µm) to the Far Infrared (55µm). The material is very resistant to shock and rapid changes in temperature, but may degrade in atmospheric conditions. A protective coating is highly recommended; typically this includes moisture resistant antireflective coatings and broadband antireflective coatings where the material is exposed.

Typical applications include components for imaging systems, analytical instruments, infrared spectroscopy and FTIR (Fourier Transform Infra-Red) instrumentation as well as numerous uses in the medical instrumentation. When the compound is doped with thallium, it becomes a good scintillator that emits in the range that silicon photodiodes respond to. It is thus a good detector for high energy particles.

Caesium iodide transmits above 80% between 0.40-40µm and has the widest transmission band of widely available IR materials. It is very soft with a hardness of HK20 and is thus very difficult to polish.

Knight Optical supply a range of quality caesium iodide optical components including caesium iodide windows, caesium iodide prisms, and caesium iodide blanks either from stock or bespoke custom parts made to your specification for a range of applications. Every component is individually tested by our highly skilled technicians in our state of the art metrology lab to ensure all components meet our high quality standards.

Contact our multilingual technical sales team and discover how Knight Optical’s high quality caesium iodide optical components and service can improve your instrumentation and supply chain experience.

Our 2018/2019 Catalogue

Inside Knight Optical’s catalogue you’ll find details of the industries we serve as well as the many other services we can offer. It also showcases hundreds of our most popular products, supported by useful technical information, to help you choose the right part for your application.
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