Far-infrared bandpass filters from perforated metal screens.
نویسندگان
چکیده
Precision nickel printing screens are shown to be very useful as far-infrared bandpass filters. For a range of such regularly perforated sheets, transmission peaks of ~ 0.9 have been observed to lie at frequencies between 60 and 140 cm(-1). We found that this value shows little degradation by cascading several screens, but the overall filter Q value may be increased from 2.7 to a value of ~ 6. These screens have considerable advantages over conventional far-infrared bandpass filters in terms of strength, optical characteristics, and cost.
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عنوان ژورنال:
- Applied optics
دوره 33 1 شماره
صفحات -
تاریخ انتشار 1994