PerkinElmer Spotlight 400 Series, User Manual

Page: 31 / 120

Overview of the Spotlight Imaging System . 31
Modes of Operation
The imager has three main modes of operation, namely Image mode, Point mode, and ATR
Imaging mode.
In Image mode you can quickly produce an IR image from a particular area of the sample.
Simply indicate the area you want to scan by drawing a box around it, and then click a
button to collect the IR image. From the image, individual spectra can be extracted for any
point on the sample.
SpectrumIMAGE software also enables you to mark points of interest on the sample. In Point
mode, you can collect individual spectra (either at the current aperture position or at
positions you have marked) with or without an ATR objective. You can also collect spectra at
regularly spaced intervals along a line (line-scanning) or within a marked area (mapping).
NOTE: Point mode is not available if you are using the Spotlight with Long Wavelength
option.
The ATR Imaging mode is only available to users of the
Spotlight ATR Imaging Accessory
(part number L1860320). It allows you to collect data from an area of the sample surface
with a spatial resolution up to four times better than conventional reflection or transmittance
IR imaging techniques.
NOTE: Diffuse reflectance mode increases the gain of the detector to compensate for the
loss of signal from poorly reflecting surfaces. This may cause saturation of the
detector in some circumstances, in which case you should use the reflectance mode.
For further information on each of these modes, see the SpectrumIMAGE software on-screen
Help.
Mode Samples
Image mode Transmittance Thin solids, fibers, films
Reflectance Polished or smooth surfaces
Diffuse Reflectance Rough or poorly reflecting surfaces, powders
Point mode Transmittance Single areas between 10 μm and 100 μm of thin
solids, fibers and films
Reflectance Single areas between 10 μm and 100 μm of
polished or smooth surfaces
Diffuse Reflectance Single areas between 10 μm and 100 μm of rough
or poorly reflecting surfaces and powders
With ATR objective Non-reflecting sample surfaces (use with care on
hard surfaces)
ATR Imaging
mode
With ATR Imaging
Accessory
Single rectangular areas (sides typically between
25 μm and 500 μm) of a rough or poorly reflecting
sample surface