

Bespoke Ordering Available

Knight Optical is a provider of AMTIR (Amorphous Material Transmitting Infrared Radiation) components, including AMTIR-1 glass, a high-performance chalcogenide material known for its optical properties. AMTIR-1, with its unique composition of Ge33As12Se55, offers a broad transmission range from 0.75 to 14µm, making it ideal for a wide array of infrared applications.
Our AMTIR-1 products, renowned for their high precision, are designed to meet the specific needs of our clients. Whether you’re looking to buy custom resolution charts crafted from AMTIR glass or need specialized components like windows, lenses, and prisms, Knight Optical can supply AMTIR-1 components tailored to your specifications. We also offer a variety of coatings, including broadband antireflective (BBAR) and diamond-like carbon (DLC), to enhance the performance of your AMTIR-1 glass components.
For those curious about the capabilities of AMTIR-1 and how it can be integrated into your project, or if you’re looking to buy custom AMTIR-1 resolution charts, our team is on hand to assist. Discover how Knight Optical’s AMTIR-1 solutions can improve your project by contacting our technical sales team today.

Speak to our experts about your Custom AMTIR needs today
Call +44 (0)1622 859444Make a quick enquiry about Custom AMTIR Now
Dive into the forefront of optical solutions. Got questions about an optical product? Reach out now and let our expertise guide you.
Optical Properties and Metrology Testing
The refractive index of AMTIR-1, at 2.4981 @ 10µm, alongside its high density and low melting point, makes AMTIR-1 an excellent choice for applications requiring optical testing and resolution testing. This includes but is not limited to resolution charts for microscopes and thermal imaging systems, where the AMTIR-1 refractive index plays a critical role in system performance.
Knight Optical’s commitment to quality is reflected in our testing procedures. Each AMTIR-1 component undergoes extensive evaluation in our metrology laboratory to ensure it meets our high standards. This attention to detail ensures that our AMTIR-1 glass, including AMTIR-1 Ge33 As12 Se55 glass, delivers performance in your applications.
Transmission Range | 0.75 to 14.0µm |
---|---|
Refractive Index | 2.4981 @ 10µm |
Density | 4.4 g/cm3 |
Melting Point | > 360°C |
Hardness | 170 |
Diameter | Windows: < 5mm to 200mm+, Lenses: < 5mm to 150mm+ |
---|---|
Form error (@633nm) | < 0.25 waves |
Centration/parallelism | < 1 arc minute |
Scratch/dig | < 40/20 |
Typical coatings | BBAR coating @ 2-14µm, DLC coating @ 2-14µm |
Frequently Asked Questions
-
What is AMTIR and its common applications?
-
AMTIR stands for Amorphous Material Transmitting Infrared Radiation. It is a type of glass used primarily in infrared optics due to its high transmissivity in the infrared spectrum. AMTIR is commonly used in thermal imaging, night vision equipment, and other IR applications where clear infrared transmission is crucial. Its unique properties make it ideal for lenses, windows, and optical systems requiring efficient infrared radiation transmission.
-
What are the key properties of AMTIR glass?
-
AMTIR glass is known for its excellent infrared transmission, low glass transition temperature, and good resistance to thermal shock. It typically has a low refractive index and high density, which contribute to its effectiveness in infrared applications. AMTIR glass is also chemically stable and resistant to water, making it suitable for use in a variety of environments and conditions.
-
What is the refractive index of AMTIR-1 glass?
-
The refractive index of AMTIR-1 glass typically ranges around 2.50 to 2.60 at mid-infrared wavelengths (around 10 micrometres). This high refractive index allows for efficient infrared light focusing and minimal dispersion, making AMTIR-1 an excellent choice for infrared optical systems.
-
How does AMTIR-1 compare to other infrared materials?
-
AMTIR-1 compares favorably to other infrared materials like germanium and zinc selenide, offering a unique balance of optical and thermal properties. While materials like germanium have higher refractive indices, AMTIR-1 provides better transmission in certain infrared bands and is less susceptible to thermal variation. Its specific composition, Ge33 As12 Se55, offers distinct advantages in terms of cost and application versatility compared to other IR materials.
-
Can AMTIR glass be customised for specific optical needs?
-
Yes, AMTIR glass can be customised for specific optical needs. It can be precision-molded or machined into various shapes and sizes, coated for enhanced performance, or integrated into complex optical assemblies. Customisation allows AMTIR glass to meet the specific requirements of different infrared applications, from medical imaging devices to industrial sensors.
-
Where can I purchase AMTIR-1 glass components for my optical system?
-
AMTIR-1 glass components can be purchased from suppliers specializing in infrared and optical materials, such as us at Knight Optical. We offer a range of AMTIR products, including lenses, windows, and custom-shaped components, tailored to meet the specific needs of your optical systems. Consulting with their experts can help you select the right AMTIR-1 components for your application, ensuring optimal performance in your infrared devices.
Is your question not here?
We are ready and waiting to answer any queries you may have about AMTIR.
Additional Information
Chalcogenide Glass
A chalcogenide glass is produced, as the name implies, from a chalcogen chemical element.
AMTIR-1 Production
AMTIR-1 is manufactured from selenium, germanium and arsenic.
Germanium Pairing
Though its optical properties are similar to germanium, as well as its similar density, it has a lower refractive index, meaning it pairs well with germanium in an achromatic doublet for colour correction within an optical system.
Refractive Index
AMTIR-1 has a low change in refractive index with temperature which is beneficial in systems with temperature fluctuations where it can prevent thermal defocussing.
Considerations
Temperature
AMTIR-1 has a maximum operating temperature of 300°C.
Wavelength Range
It performs well in the 8-12µm wavelength range where both its dispersion and absorption are at their lowest.

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.

Operating for over 30 years
Knight Optical has been operating for over 30 years, with our managing director Colin Overton at the helm. Over this time, we have become a global leader in the production and distribution of scientific optical components and bringing quality into focus for all of our products and services that we provide.
Our 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.
Click below to view our digital catalogue now.