An increasing demand for notchfilters arises from biomedical applications. In typical set-ups for fluorescence analysis, notchfilters separate the exciting light from the fluorescence light emitted by the sample. Specific notch filters have the capability to reject several laser wavelengths, e.g. 488 and 561 nm. Notch filters in medical instruments block the high light intensity of a laser source while retaining a colour-accurate view for the operator.

Notchfilters produced by mso jena reject a specific narrow wavelength range, while providing high transmittance for the remaining part of the spectrum. Typically, a blocking of OD 5 is achieved in the stopband and T > 90% in the passband between 350 and 800 nm. The spectral distance between passband and blockband is below 2% of the blocked wavelength.

The production of notchfilters requires a highly stable and reliable coating process for multilayers composed of 200 and more individual layers. In the past, ion beam sputtering was the favoured method for notch filter production. In recent developments of mso jena, plasma-assisted magnetron sputtering has proven to be a valuable tool for the deposition of high-quality notch filters at high deposition rates. Its specific know-how for filter design and process implementation enables mso jena to manufacture customized notch filters cost-efficient and within short time.