AvaSpec services and calibrations

Wavelength calibration
All AvaSpec spectrometers standard come with a wavelength calibration and coefficients to calculate wavelength from pixelnr which are installed on-board, inside of the AvaSpec’s EEPROM.
Under normal conditions the wavelength calibration does not need to be redone, since the spectrometers have no moving elements inside. If a wavelength shift is measured vs. the original wavelength calibration, then the spectrometer can be recalibrated by the end-user, using the Avalight-CAL with the auto-calibration software routine in AvaSoft-FULL.
As an option the spectrometer can also be returned to Avantes for recalibration, called Spectral-cal-service. Before returning the spectrometer an RMA authorization number needs to be obtained.

Non-linearity Calibration
Most detectors of the AvaSpec spectrometers have a good linear behavior in their intensity output, which means that there is a better than 95% correlation between raw signal in A/D counts and the light intensity at the spectrometer entrance.
However for some applications, which require a wide dynamic range, such as highly absorbing substances or low light level applications, combined  a high accuracy a non-linearity calibration of the detector is recommended. This NL-calibration is performed on the detector array and the output signal is linearized to better than 99%.
A complete report and the calculated NL calibration coefficients are delivered with the spectrometer.
For irradiance calibrations the NL-calibration is automatically included.

Irradiance calibration
Applications that use the spectrometer to measure the light energy of unknown sources require an irradiance calibrated spectrometer.
For all AvaSpec spectrometers both irradiance and radiance calibrations can be offered. Irradiance calibrations (µW/cm²) are normally performed on a system with a fiber optic cable and a cosine corrector or integrating sphere. Radiance calibrations (µW/cm²/sr) can be performed on a spectrometer and a bare fiber or fiber with collimating lens looking at a diffuse illuminated surface.
The (ir)radiance calibrations can be performed for 3 different wavelength ranges, UV (200-400nm), VIS (360-1100nm) and NIR (1100-2500nm). All systems are calibrated versus an NIST traceable irradiance calibration standard and come with a complete report and calibration files, which can be loaded directly in AvaSoft-IRRAD.
More information on irradiance can be found in the software section (AvaSoft-IRRAD – page 45) and the section applications – irradiance measurements, page 118.
Alternatively irradiance calibrated light sources, such as AvaLight-DHS-Cal and AvaLight-HAL-CAL are available to perform your own irradiance calibration.