Filtering coatings (interference filters) are designed to separate the required spectral range from the continuous radiation spectrum.
Beamsplitting coatings are designed to separate the incident beam into reflected and transmitted ones with a given intensity ratio.
Depending on the purpose, filters are subdivided into blocking (cut-off), narrowband and bandpass.
Mid-IR coatings
Cut-off filter 9.3-15.3μm
Cut-off filter up to 8 μm on Ge.
The adhesion of the coating is checked with adhesive tape.
The coating can withstand wiping with a cotton swab dipped in acetone.
Cutting filter 15.5-20 µm
Cut-off filter up to 12 microns on Ge and ZnSe (the filter is assembled in a single frame of two components).
The adhesion of the coating is checked with adhesive tape.
The coating can withstand wiping with a cotton swab dipped in acetone.
ZnSe - HR 10.6 μm; HT 3.7-4.8 μm
Reflective coating at 10.6 μm with simultaneous transmission of 3.7-4.8 μm on ZnSe.
The adhesion of the coating is checked with adhesive tape.
The coating can withstand wiping with a cotton swab dipped in acetone.
Transmission of a ZnSe plate at an angle of 45 degrees is presented.
Various mid-IR bandpass filters
Filters can be made on silicon, germanium and sapphire substrates.
The adhesion of the coatings is checked with adhesive tape.
The coatings have passed the mechanical endurance test (according to the instructions in paragraph 4.5.11 of MIL-C-675C).
The filters can be used in gas analysis devices, for examination of the combustion of flames in furnaces, for detection of sources of carbon dioxide and more.
If necessary, it is possible to manufacture filters with the characteristics specified by the customer.
Beam splitter for the range 2-25 on KBr
The adhesion of the coating is checked with adhesive tape.
The transmission of a plate with a protective coating on one side and a beam splitter on the other is presented.