User`s guide

Performance Tests Optional Performance Tests
142 Agilent 81600B Tunable Laser Source Family, Fourth Edition
Dynamic Absolute and Relative Wavelength
Uncertainty
This section describes the analysis steps leading to dynamic absolute and
relative wavelength uncertainty with reference to a single sweep speed.
Repeat them until all the sweep speeds of interest have been covered.
The only measurement results to be considered here are the deviations
from the reference sweep:
λ
LOGGED
(i, n) i = 1, 2, ... 60 x 2, n = 1, ... 5 (scan repetition)
Their intuitive meaning is the additional error in the TLS wavelength
measurements caused by the continuous-sweep mode (at the speed of
interest). Such additional error is evaluated at fixed control points,
positioned in different wavelength intervals.
The results from all intervals should here be merged in a single array, since
the final specification must hold for the whole TLS wavelength range.
Analysis
28 Select the data λ
LOGGED
(i, n) corresponding to the sweep speed of
interest;
29 Compute (for each scan) the half of the peak-to-peak value over
wavelength:
∆λ
LOGGED
(n) = º * { max[∆λ
LOGGED
(i, n)] Ð min[∆λ
LOGGED
(i, n) ] }
30 Compute the average offset over wavelength for each scan:
∆λ
OFFSET
(n) = avg [∆λ
LOGGED
(i, n))]
31 Retrieve the results of the static (stepped mode) wavelength accuracy
tests:
• let
λ
REL STATIC
be the value to be compared with the
test limit for relative wavelength accuracy;
• let
λ
ABS STATIC
be the value to be compared with the
test limit for absolute wavelength accuracy.
32 Compute a Dynamic Relative Wavelength Uncertainty (see Definition of
Te r ms ) R(n) for each scan, by combining static and dynamic
uncertainties using:
R(n) = sqrt[ (
λ
REL STATIC
)
2
+ ( ∆λ
REL
(n))
2
]
33 Compute a Dynamic Absolute Wavelength Uncertainty (see Definition
of Terms) A(n) for each scan, by combining static and dynamic
uncertainties using:
A(n) = R(n) + | (
λ
ABS STATIC
- λ
REL STATIC
) + ∆λ
OFFSET
(n) |