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Change due to temperature

Temperature changes affect a filter's performance due to thermal expansion and contraction of the materials used to construct them. Most filters are designed and specified for operating at 23 tex2html_wrap_inline5509 C, and deviations from this value in the range of -60 tex2html_wrap_inline5509 C to +60 tex2html_wrap_inline5509 C will produce peak wavelength shifts approximately linear with temperature. The exact shift coefficient will depend on the particular design wavelength of the filter, and, typically, ranges between 0.2Åand 0.3Å per  tex2html_wrap_inline5509 C at 4000Åand 6500Årespectively. Bandwidth and peak transmission changes observed are relatively minor, of the order of 0.01Å per  tex2html_wrap_inline5509 C and 0.013Å  per  tex2html_wrap_inline5509 C respectively.

The interference filters were specified for working at 10 tex2html_wrap_inline5509 C, so temperatures significantly different from this will affect the effective central wavelength of the filters.

For example, at an ambient temperature of 0 tex2html_wrap_inline5509 C, an tex2html_wrap_inline6487 filter with specified central wavelength 6556Åwill have an effective central wavelength of 6553Å.

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Wed Sep 17 12:36:20 BST 1997