Agilent Technologies 86038B User Manual page 233

curve fit, although more affected by noise and
5th Order Sellmeier
instabilities in the measurement path, provides more general
purpose curve fitting. The five-term Sellmeier fit can yield
multiple zero-dispersion wavelengths. All the values and their
associated slopes are shown in the graphs. The system searches
for dispersion zeros in a wavelength range equaling
approximately five times the measurement span (2.5 times each
side of the center wavelength). This allows identification of
zero-dispersion wavelengths which fall outside of the
measurement range. In some cases, due to the peculiarity of the
five-term Sellmeier fit, zero-dispersion wavelengths found
outside of the measurement range may not correspond to actual
zero-dispersion wavelengths of the device under test. The
4 2 -2 -4
equation is in the form: Ax + Bx + C + Dx + Ex .
Parameters
ByVal CurveFitName As String - The short name of the curve fit.
A list of the curve fit names can be retrieved via the Catalog
command.
Returns
String - Contains a description of the curve fit.
VB.NET Syntax
Dim desc As String
desc = pdlaClient.Analysis.CurveFit.Description("Quadratic")
VB 6.0 Syntax
Dim desc As String
desc = pdlaClient.Analysis.CurveFit.Description("Quadratic")
ShortName Method
Returns the short name of the curve fit. That is, linear,
quadratic, Sellmeier-3, or Sellmeier-5.
Parameters
ByVal CurveFitName As String - The name of the curve fit. A list
of the curve fit names can be retrieved via the Catalog
command.
Agilent 86038B Photonic Dispersion and Loss Analyzer, Second Edition
233