Dielectric Filters

Filters are optical elements with specific spectral transmission characteristics. They are used to modify the properties of a light source or to block unwanted wavelengths of light. Dielectric filters absorb very little light. The functionality is based on reflection of the unwanted spectral region ...Read more

Filters are optical elements with specific spectral
transmission characteristics.
They are used to modify the properties of a light
source or to block unwanted wavelengths of light.

Dielectric filters absorb very little light. The
functionality is based on reflection of the
unwanted spectral regions based on optical
interference within the layer structure of the
filter coating.



Filters are optical elements with specific spectral transmission characteristics. They are used to modify the properties of a light source or to block unwanted wavelengths of light.

Dielectric filters absorb very little light. The functionality is based on reflection of the unwanted spectral regions based on optical interference within the layer structure of the filter coating. These filters can be manufactured for use in the UV, visible and IR.

In order to reduce the number of coating layers - and thus the cost - a combination may be made by dielectric coating a colour (absorption type) glass substrate. This is common for some bandpass filters.

We offer filters cut to any shape. Black anodized aluminium rings may be provided for ease of mounting.

In addition to our customized products, we also offer a series of standard visible bandpass filters at a selection of wavelengths (see “Downloads”).

Range of dimensions: 2mm – 300mm

Highest available surface figure: λ/4 (DIN: 3/0,5)

Highest available surface quality: 40-20 S/D (DIN: 5/2x0,16)

Highest available tolerance of beam deviation: 3” (arcsec)

Blocking: OD3 (standard); OD5 (high blocking)