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Infrared IR Filters

REFLEX Analytical complements their product line of infrared optics and lenses with infrared (IR) filters. An IR filter is an optic which is specifically fabricated to remove visible light and only pass infrared light. In military, security and surveillance applications the near and mid-infrared are of most interest, and these are usually divided into the shortwave infrared band between 0.7 and 4µm, the midwave infrared band between 4 and 6µm, and the longwave infrared band between 8 and 15µm. Why the different infrared labels? For military applications what is of interest is the radiation that can penetrate the atmosphere and be detected. It turns out that the short, mid and longwave infrared bands correspond to those wavelengths that easily penetrate air without being rapidly absorbed or scattered. The shortwave infrared band is associated with jet engine exhausts, gun barrel exhaust gases, munition explosions and other hot objects. The midwave infrared band is associated with running turbine and piston engines, and other high temperature operating objects. The longwave infrared band is associated with human body heat, structures or buildings, and other objects at similar temperatures. REFLEX Analytical offers a series of four IR filter types depending upon the application's requirement. Each IR filter type is wavelength and application dependent. Scroll below for examples and more information about IR filters. Contact REFLEX Analytical to discuss your requirement.

The export of this product without proper licensing is strictly prohibited and falls under ITAR per title 22, CFR, parts 120-130. Please contact REFLEX Analytical Corporation to receive further information on how to obtain proper licensing from the U.S. Department of State.

Near Infrared (700 - 1100nm) Bandpass Filter and mid range Near IR filters block greater than 99% visible light

Mid-Infrared Bandpass Filters (CWL 2.70µm, 2.95µm, 3.46µm, 3.6µm, 4.0µm, 4.26µm, 4.67µm, 5.30µm, 10.0µm and 10.6µm) CLICK HERE to download the product sheet.

1.1 - 25µm Infrared Broadband Filter greater than 50% transmittance between 1.1 - 25µm (cut on wavelength 1.01µm) blocking less than 0.10% transmittance from UV - 1µm

8 - 12µm Infrared Bandpass Filter average 80% transmittance between 8 - 12µm blocking less than 0.10% transmittance from UV - 20µm

Near Infrared Bandpass Filter

Infrared filters are made from specialty optical materials and coatings. For instance, specific Near IR bandpass filters are made from a complex composition. They can block over 99% of the visible light spectrum from “white” light sources such as incandescent filament bulbs . This series of infrared filter permits maximum infrared output while maintaining extreme covertness and is used around the world in military and law enforcement applications. All generations of night vision devices are greatly enhanced with the use of such Near IR bandpass filters. Contact REFLEX Analytical to discuss your application. Various stock sizes are available. Custom components are encouraged and quoted upon request. Specify the desired operating wavelength and substrate dimension.

Infrared Broadband Filter

The 1.1 - 25µm infrared filter is typically used to detect infrared radiation remotely to determine the temperature of objects. This is termed thermography and also know as forward looking infrared (FLIR). Thermography (thermal or FLIR imaging) is mainly used in military, law enforcement and industrial applications but the technology has reached the public market in the form of infrared cameras on automobiles. Thermographic and FLIR cameras detect radiation in the infrared range of the electromagnetic spectrum (0.9 - 14µm) and produce images of that radiation. FLIR devices allow personnel to see objects in total darkness, through smoke, and other challenging conditions without revealing their presence or offering awareness the perimeter is being monitored. Night vision devices are not required with thermal or FLIR imagers since heat generating objects reveal themselves. Contact REFLEX Analytical to discuss your requirement. Available sizes include 1.0", 2.0" and 3.0" diameters. Custom components are encouraged and quoted upon request.

Infrared Bandpass Filter

The 8 - 12µm infrared bandpass filter is used in many applications including infrared tracking (also known as infrared homing). Infrared homing is a passive system in which heat generated by the target is detected and homed on. Typically used in the anti-aircraft role to track the heat of jet engines. In the case of passive missile guidance systems, missiles which use infrared seeking are often referred to as "heat-seekers". Many objects such as vehicle engines and aircraft generate and retain heat, and as such, are especially noticeable in the infrared wavelengths of light compared to objects in the background. Early infrared seekers were most effective in detecting infrared radiation with shorter wavelengths, such as the 4.2µm emissions of the carbon dioxide efflux of a jet engine. Modern infrared seekers operate in the 8 - 12µm wavelength range, which is absorbed least by the atmosphere. For example, generally longer wavelength infrared (LWIR) 8 - 12µm will suffer less signal transfer than shorter wavelength IR (SWIR) in haze and fog. Contact REFLEX Analytical to discuss your requirement. Available in a 1.0" diameter. Custom components are encouraged and quoted upon request.