Light Range
Beamsplitter
Detector
Spectral Range (cm
-1
) Source
mid-IR
KBr
DTGS-KBr
7,400 - 350
ETC
MCT-A
‡
7,400 - 600
ETC
MCT-B
‡
7,400 - 400
ETC
DTGS TEC
7,100 - 350
ETC
DTGS-CsI
6,400 - 350
ETC
CsI
¶
DTGS-CsI
6,400 - 225
ETC
MCT-A
‡
6,400 - 600
ETC
MCT-B
‡
6,400 - 400
ETC
ZnSe
DTGS-KBr
4,000 - 650
ETC
MCT-A
‡
4,000 - 650
ETC
MCT-B
‡
4,000 - 650
ETC
DTGS TEC
4,000 - 650
ETC
DTGS-CsI
4,000 - 650
ETC
far-IR Solid-Substrate
DTGS-PE
700 - 50
ETC
Si bolometer
700 - 20
ETC
Notes:
* This spectral range reflects the combination of the ranges of the ETC and white light sources, as well as the limits of the beamsplitter-
detector combination. The range achieved using one of these sources will not be as broad as the total range shown.
†
Si detectors can be used only with a white light (tungsten-halogen) source.
‡ These detectors must be cooled with liquid nitrogen before use.
§
InSb detectors will not produce a signal under intense light. During installation and alignment, start with the smallest aperture setting.
¶
CsI beamsplitters are extremely hygroscopic (sensitive to moisture).
Nicolet FT-IR User’s Guide 63