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Custom Zinc Sulphide

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Find out more about our custom zinc sulphide

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Global leaders in custom optical solutions
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All optical components 100% QA checked
ISO14001 & ISO9001 certified

Knight Optical offers a wide range of zinc sulphide optics tailored to meet your specific needs, whether for scientific, industrial, or defence applications. Our zinc sulphide products include both Multispectral (MS) and Forward Looking Infrared (FLIR) grades, catering to a broad spectrum of infrared applications.

Our Multispectral zinc sulphide is expertly created, undergoing hot isotropic pressing (HIP) to enhance its optical clarity and reduce defects, making it an excellent choice for applications requiring minimal scattering and low absorption across a broad transmission range from 0.35 to 12 µm. This makes our zinc sulphide optics, such as zinc sulphide windows and zinc sulfide lenses, ideal for multifaceted systems that operate across visible and infrared spectrums.

The FLIR grade, alternatively known as regular zinc sulphide, is specifically tailored for thermal imaging, prominently in the 8 to 12µm range. Despite its lower transmission in the visible spectrum, this grade of zinc sulphide excels in durability and resistance, making it suitable for harsh environmental conditions.

At Knight Optical, we pride ourselves on supplying zinc sulphide optics at competitive prices. Our zinc sulphide optical windows and lenses are available with a range of coatings, including broadband antireflective (BBAR), to meet the demanding specifications of your projects.

Should you require something unique, our team is on hand to guide you through the customization process of your zinc sulphide optics, ensuring that you receive components that perfectly fit your application needs.

Speak to our experts about your Custom Zinc Sulphide needs today

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Make a quick enquiry about Custom Zinc Sulphide Now

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    Optical Properties of Zinc Sulphide

    Our state-of-the-art metrology laboratory ensures that each zinc sulfide lens and window meets the highest quality standards before reaching you. We understand the diverse uses of zinc sulphide in the industry and are committed to providing components that improve the performance and efficiency of your optical systems.

    For those interested in enhancing their systems with fluorescent zinc sulphide or other specific requirements, Knight Optical’s expertise and extensive range can accommodate your needs. Contact our technical sales team to discuss your requirements and discover how our zinc sulphide solutions can benefit your projects.

    Transmission Range – FLIR Grade1.0 to 13µm
    Refractive Index – FLIR Grade2.192 @ 10.6µm
    Density – FLIR Grade4.08 g/cm3
    Melting Point – FLIR Grade1827°C
    Hardness – FLIR GradeKnoop 240 with 50g indenter
    Transmission Range – Multispectral Grade0.37 to 13.5µm
    Refractive Index – Multispectral Grade2.20084 @ 10µm
    Density – Multispectral Grade4.09 g/cm3
    Melting Point – Multispectral Grade1827°C
    Hardness – Multispectral GradeKnoop 160 with 50g indenter
    Diameter< 5mm to 100mm +
    Form error (@633nm)< 0.25 waves
    Centration/parallelism< 1 arc minute
    Scratch/dig< 60/40
    Typical coatingsSingle sided BBAR @ 2-14µm

    Frequently Asked Questions

    Zinc sulphide is commonly used in infrared optics due to its excellent transmission properties from the visible wavelengths into the far infrared. It is employed in various optical components like windows, lenses, and domes, especially for thermal imaging systems, FLIR (Forward Looking Infrared) applications, and night vision technology.

    Zinc Sulfide lenses are notable for their high refractive index and low absorption coefficient, making them highly efficient for infrared applications. Unlike materials such as germanium, which are cloudy in the visible spectrum, zinc sulfide offers some transmission in the visible range, providing versatility for multi-spectrum applications.

    Fluorescent Zinc Sulphide contains trace amounts of metallic impurities, which allow it to glow or fluoresce under ultraviolet light. This characteristic makes zinc sulphide valuable for applications such as display screens, luminous paints, and safety signs that require visibility in low-light conditions.

    The price of Zinc Sulphide can vary based on factors such as purity, processing techniques, and market availability. Generally, it is competitively priced with other infrared materials, offering a cost-effective solution for many applications requiring its unique properties.

    There are several types of Zinc Sulphide optics available, including clear Zinc Sulphide, which has been hot isostatically pressed (HIP) for better optical quality, and multispectral Zinc Sulphide, which is treated to improve transmission across a wider range of wavelengths. These optics can be found as lenses, windows, and other components in various dimensions and finishes to suit a wide array of applications.

    When selecting Zinc Sulfide optical windows, you should consider the specific transmission requirements of their application, especially the required wavelength range. Additionally, factors such as thermal properties, strength, durability, and resistance to environmental factors should be evaluated based on operational conditions. Finally, compatibility with other system components and overall budget constraints are also critical considerations.

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    We can offer antireflective (BBAR) coatings for your zinc sulphide.

    Typical Applications

    Silicon Optics for Infrared Filter Substrates

    Systems with visible and infrared sensors

    Multispectral zinc sulphide is often used in systems which have visible and MWIR/LWIR sensors due to its broad transmission band and low absorption.

    Military systems

    FLIR grade zinc sulphide can be used as a front optic in many systems, especially those operating in the 8-12 micron thermal band. With a higher fracture strength anda hardness compared to MS grade, it is better suited as a front optic, as it shows better chemical and particle resistance.

    Get in touch with us:

    With our in-house state-of-the-art metrology laboratory you can be confident that your optical components will meet your requirements. You can find out more about our testing facilities here.

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