The manufacture and spectral assessment of the filters and antireflection coatings for use in the HIRDLS instrument
R Hunneman, G J Hawkins
SPIE Proceedings, 3437, Pages 378-390 (1998)
This paper describes the design and manufacture of the filters and antireflection coatings used in the HIRDLS instrument. The multilayer design of the filters and coatings, choice of layer materials, and the deposition techniques adopted to ensure adequate layer thickness control is discussed. The spectral assessment of the filters and coatings is carried out using a FTIR spectrometer; some measurement results are presented together with discussion of measurement accuracy and the identification and avoidance of measurement artefacts. The post-deposition processing of the filters by sawing to size, writing of an identification code onto the coatings and the environmental testing of the finished filters are also described.