IR filter / Heat-reflecting filters

Infrared filters (Heat-absorbing filters), commonly known as "IR filter" are often used for generating a light similar to sunlight (artificial sunlight) or in order to remove the unwanted rays in the near-infrared region (NIR) from the light beam.

The IR3 heat reflecting filter should allow the visible part of light to pass through without any change in colour; this can be clearly seen in the photo.

The image clearly shows that the heat-reflection filter transmits the light without any colour distortion. On the contrary, the heat component of the light is reflected by this IR filter.

Glass types and sizes

The IR filters are offered in the following materials / thicknesses / sizes

In addition, we also provide even smaller filter sizes with less material thickness. We can cut the filters round as well as in any other shape – please see Customised Glass Cutting Service.

All technical data can be found here:


Standard glass thicknesses

Float glass2 mm3 mm4 mm5 mm6 mm
Borofloat1.1 mm2 mm3.3 mm5.5 mm6.5 mm
Clear glass2 mm3 mm4 mm5 mm6 mm

Standard sizes

minimumin mm range depending on material
maximumgross 1,150 x 850 mm / net 1,080 x 800 mm


Spectral curve FE Red


Beam cooling

Nearly all powerful light sources emit not only useful light but also superfluous or unwanted frequencies, leading to further heating of the illuminated objects. Based on the standard substrate Borofloat, our IR filters can be used to remove any unwanted rays in the near-infrared region (NIR) from the light beam.

Our standard IR filters for beam cooling

Filter typesSpectral position of reflection 
IR2870 - 950 nm/media/223
IR3850 - 900 nm/media/224
IR4800 - 850 nm Filter with higher UV transmission / Sun simulation/media/225
IR5800 - 900 nm/media/226
IR7850 - 900 nm/media/229

Sun simulation

Various applications require light which is as similar to sunlight as possible.  With this, for example, you can test the electronic performance of photovoltaic cells and modules. Or you can use light which is similar to sunlight for testing material ageing.  The heat-reflection filters are matched exactly to the light sources used (continuous wave and flash) and customised versions are manufactured for both applications.

We produce IR filters for generating light similar to sunlight (sun simulation).

IR filters for sun simulation

Filter typesSpectral position of Reflection 
IR filterCustomised filters 

An overview of all our optical filters for industry can be found here

All filters for industry 


Whitepaper optical filters


Whitepaper glass coatings


Our consulting service

As a customer-focused manufacturer, we are here to support with advice and measures that will help bring your projects to life.