Ocean Optics Ocean View Install - Manual (Page 57)

4: Wizards
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4. Set Acquisition Parameter controls.
5. Store Reference spectrum.
6. Store Background spectrum.
7. Select Color Temperature. Set the color temperature of the light source used for the reference
spectrum. The color temperatures of several Ocean Optics light sources are shown in the table.
Click on any of the sources in the table to populate the Color Temperature box at the top of the
window with the appropriate value.
Absolute Irradiance
Irradiance is the amount of light present on a particular area, such as the fiber’s cross-section at its tip, a
cosine corrector’s surface, or the integrating sphere’s surface (measures the total optical output of a light
source inserted into the integrating sphere).
Absolute Irradiance Mode calculates the true irradiance of a spectrum, displayed in actual uW/cm^2/nm
(or uW/nm when using an integrating sphere) incident on the probe’s collection area. You do not need to
store reference spectrum first since absolute irradiance is not relative to another measurement. However,
you must store a background spectrum and have a calibration file before you can measure absolute
irradiance.
If your spectrometer was calibrated by Ocean Optics, you should have received a CD containing the
Radiometric Calibration Files specific to your spectrometer. If you have these files, select Get Irradiance
Calibration from File.
If you do not have these files, select New Calibration to create your own spectrometer calibration files
using calibrated light sources that have known spectral output (microwatts per square centimeter per
nanometer).
►
Procedure
1. Invoke the Absolute Irradiance wizard by clicking the Create new spectroscopy application icon
.
2. Select either an active acquisition or start a new one.
3. Click Spectroscopy, then Absolute Irradiance, then Next.
4. Select the calibration source to begin the irradiance calibration of your spectrometer:
- Get Irradiance Calibration from File: Loads a previous irradiance calibration using an
existing .cal or .IrradCal file.
- New Calibration: Creates a new irradiance calibration for the spectrometer using a calibrated
light source and associated lamp file (.lmp). This option also allows you to save the new
calibration as a .cal file that can be loaded at a later time.
5. Load a previous irradiance calibration file into the wizard. The file must be a .cal or .IrradCal
file. The spectrometer serial number and collection area will be automatically set based on
information stored in the file. The message in the lower left corner of the window will update
upon successful loading of the calibration file.
6. Load the lamp file that is associated with the calibrated light source used for the irradiance
calibration. The file must be a .lmp file. The message in the lower left corner of the window will
update upon successful loading of the lamp file.