Agilent Technologies 8163A Programming Manual page 175

Lambda Scan Applications
Agilent 8163A Lightwave Multimeter, Agilent 8164A Lightwave Measurement System, & Agilent 8166A Lightwave Multichannel
System, Third Edition
The disadvantage of using equally spaced datapoints is that the linear
interpolation is analogous to the use of a low pass filter. Figure 17 shows
the original curve as measured directly by a Power Meter and the
interpolated curve. Interpolation will always tend to produce a smoother
curve by rounding off any peaks in the curve.
Figure 17 Equally Spaced Datapoints
The Agilent 816x VXIplug&play Instrument Driver
Original
Curve
Interpolated
Curve
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