Mid-Wave Infrared Filters

MWIR Filters

Materion Balzers Optics is a leader in MWIR filters used for a wide variety of applications. We offer a number of narrowband filters for measurement of various gases and vapors by non-dispersive infrared spectroscopy. We also offer narrow and wideband filters used for measurement of temperature and flame detection. For MWIR cameras, a window can be coated with an antireflective coating on one face and a longpass filter on the other face.

Benefits

• Highly repeatable center wavelength
• Narrow bandwidth available
• High transmittance in the passband
• Long-term, shift-free spectral performance
• High environmental stability
• Customized filter sizes
• Anodized Al rings available for round filters

Applications

Non-dispersive infrared spectroscopy is used to detect and quantify the concentration of a wide variety of gases and vapors. Medical applications include quantitative measurement of CO₂ in a person’s exhaled breath for capnography, and quantitative sensing of various anesthesia gases. Industrial applications include sensing of CH₄, C₂H₆O, CO, NO, NO₂ and other gases. MWIR cameras are used for a variety of applications, including identifying and quantifying methane emissions, flame detection as well as for night vision.

Technical Data

Wavelength 

3 to 5 µm

Transmittance 

T > 80 – 95%
(depending on wavelength range)

Blocking 

up to OD4

Angle of Incidence 

standard 0°
(different AOI on request)

Bandwidth 

down to 25 nm, typical

Substrate 

Fused Silica, Sapphire, Si, Ge or ZnS

Dimensions 

Up to Ø 200 mm Si,
other sizes upon request

Surface Defects 

S/D 40/20

Environmental Stability 

Temperature -40 °C to +150 °C
Humidity up to 99%