Ocean Optics RaySphere 1700 Install - Manual (Page 58)

9: Nonlinearity Correction, Stray Light Correction and Calibration
48 RAYSPHERE-1700-02-201304
Influence of Spectrometer’s Internal Stray Light
The spectrometer’s internal stray light is defined as irregularly reflected light inside the spectrometer,
resulting in a sensor signal. Most of the incoming light is reflected and diffracted to be measured at the
detector’s active surface. A small amount of light (typical 5 x 10^-5 per photon) is reflected irregularly by
scattering or reflections from order sorting filters and optical elements. This light is not “wavelength
resolved” and causes in an increased signal at the detector.
Standard Uncertainties and Expanded Uncertainty for k = 2
The Expanded uncertainty for k = 2 is calculated from the above described factors and listed in the table
below.
Standard Uncertainties and Uncertainty Budgets
Wavelength[nm] 300 350 400 450 500 600 700 800 900 1000 1100
1. I_DC 1.45 1.20 0.95 0.80 0.65 0.60 0.60 0.55 0.55 0.55 0.50
2.,1 T and F Nk
3.,1 d
3.,2 alpha
4. Dark 0.20 0.05 0.10
5. T_TEC 0.02 0.06
6. Irr_Kal 1.50 1.40 1.30 1.20 1.20 1.05 1.00 1.00 1.00 1.00 1.00
7. d_Lambda 0.50 0.30 0.25 0.20 0.10 0.10 0.05
8. StrayL ntia
9. LinCorr 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3
Standard
Uncertainty
2.18 1.89 1.66 1.49 1.40 1.25 1.21 1.18 1.18 1.18 1.16
Expanded
uncertainty for
k = 2
4.35 3.79 3.31 2.97 2.80 2.50 2.41 2.36 2.36 2.36 2.33
The uncertainty resulting from stray light effects inside the RaySphere spectrometers cannot be neglected
for the wavelength range of 300 nm to 350 nm.
Not listed values are below 0.1 % of standard uncertainty, not known [kn] or not taken
into account [ntia].
Values are round to two positions after decimal point.