Patent ID: 8780356

Claim:
A method for determining calibration parameters for a spectrometer, wherein the spectrometer comprises a Fabry-Perot interferometer having an adjustable mirror gap, and an image sensor, the image sensor comprises a plurality of first pixels and a plurality of second pixels, the pixels are arranged to detect light transmitted through the Fabry-Perot interferometer, the first pixels have a first sensitivity function, the second pixels have a second different sensitivity function, the Fabry-Perot interferometer has a first transmission peak and a second transmission peak, the first pixels are arranged to detect light at the spectral position of the first transmission peak and the at the spectral position of the second transmission peak, the method comprising: providing first calibration light, which has a reference spectral peak at an adjustable spectral position, obtaining first detector signal values from the image sensor by coupling the first calibration light into the spectrometer when the reference spectral peak is substantially at a first spectral position, obtaining second detector signal values from the image sensor by coupling the first calibration light into the spectrometer when the reference spectral peak is substantially at a second spectral position, determining a first group of calibration parameters from the first detector signal values and from the second detector signal values, providing second calibration light, wherein the spectral width of a spectral band of the second calibration light is broader than the spectral width of the reference spectral peak, obtaining third detector signal values from the image sensor by coupling the second calibration light into the spectrometer, and determining a second group of calibration parameters from the third detector signal values and from the first group of calibration parameters.