Ocean Optics RaySphere 1700 Install - Manual (Page 57)

9: Nonlinearity Correction, Stray Light Correction and Calibration
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Misalignments
The resulting uncertainties resulting from hardware misalignments are taken into account.
Noise of Dark Level
The dark level is the signal which is recorded if the spectrometer measures the intensity of light in an
absolutely dark room. The dark signal results from the sensor’s temperature and the noise of the signal
follows Poisson’s distribution.
Influence of Sensor Temperature
The sensitivity of each silicon-based sensor depends on its temperature and changes result in a significant
change in sensitivity in the IR range from 700 nm to 1150 nm.
The figure below illustrates the effect.
Ocean Optics spectrometers have always thermalized and temperature-controlled sensors to minimize the
effect of thermal instability. The confidence interval for temperature to control the detector temperature
[TEC] is +- 0.1K.
Uncertainty of Calibration Lamp
The uncertainty of the calibration lamp is given by the manufacturer’s calibration report for an interval of
confidential of k = 2. The traceability to NIST is reported as well.
Uncertainty of Wavelength Calibration
Each wavelength calibration has an uncertainty which is reported in the wavelength calibration
documents for spectrometers from Ocean Optics. The resulting uncertainty is estimated from statistical
analysis and from typical intensity distribution of the light source.