Ocean Optics CHEM2000 - Manual (Page 15)

2: Using OOIChem Software
Cursor Properties
In this toolbar, you can label the cursor and monitor the cursor’s X value and Y value. To the right of the
X and Y values of the cursor is a cursor selection button that
allows you to choose a cursor style and a point style. You can
also choose a color for the cursor and whether or not to display
the name of the channel the cursor is currently reporting.
Finally, you can bring the cursor to the center of the spectrum
or center the spectrum around the cursor’s current position.
Text Box
This box allows you to enter an operator name and any other text to identify your experiment. This text
appears in your data files. You can edit this text at any time.
Acquisition Parameters
Integration Period
Enter a value to set the integration period in milliseconds for an active
spectrometer channel. The integration period of the spectrometer is analogous to
the shutter speed of a camera. The higher the value specified for the integration
period, the longer the detector “looks” at the incoming photons. If your scope
mode intensity is too low, increase this value. If the intensity is too high, decrease
the value. While watching the graph trace in Scope Mode, adjust the integration
period and other acquisition parameters until the signal intensity level is
approximately 3500 counts.
Average
Enter a value to implement a sample averaging function that averages the specified number of spectra.
The higher the value entered the better the signal-to-noise ratio. The S:N improves by the square root of
the number of scans averaged.
Boxcar Smooth
Enter a value to implement a boxcar smoothing technique that averages across spectral data. This method
averages a group of adjacent detector elements. A value of 5, for example, averages each data point with
5 points (or bins) to its left and 5 points to its right. The greater this value, the smoother the data and the
higher the signal-to-noise ratio . However, if the value entered is too high, a loss in spectral resolution
results. The S:N improves by the square root of the number of pixels averaged.
Reference Scan
Selecting the Reference button activates a prompt to make sure your light is on. You then must choose to
either Store or Cancel your reference scan. A reference spectrum is taken with the light source on and a
105-00000-CHM-02-0405 PRELIMINARY DRAFT 9