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666-F7A Didymium glass filter


The 666-F7A didymium glass filter made of special material is manufactured by the company Schott AG. Due to the its properties in the UV range, the didymium glass filter is also suited as an absorption filter. Therefore it can be used to check wavelength accuracy in the UV/Vis range, as well as the photometric accuracy in the UV range.

Checking the photometric accuracy in the UV range is possible at the following wavelengths: 270 nm, 280 nm, 297 nm, 320 nm and 340 nm. As a standard, the thickness of the filter is manufactured in a way that it will have an absorbance of approx. 0.5 at a wavelength of 340 nm. Consequently, absorbance values will increase with decreasing wavelengths.

Please note:

The absorption values depend on the batch and are only comparable in one glass melting. For this reason all didymium glass filters are certified individually.

E_Didymiumglas-Filter Typical spectrum of a Didymium glass filter between 270 nm and 370 nm

ApplicationTo check the photometric accuracy in the UV range (270 nm until 340 nm)
ContentDidymium glass filter in metal frame
Standard certificationPhotometric accuracy: from ca. 0,5 to 1 Abs
At wavelength: 270; 280; 297; 320; 340 nm
Slit width: 1 nm
with DAkkS calibration certificate
Possible certificationsOthere wavelengths: from 270 nm to 290 nm and from 310 to 320 nm
Slit width: all until 5 nm possible

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