US 2014/0176729 A1Published application

Method for determining calibration parameters for a spectrometer

AssigneeTeknologian tutkimuskeskus VTT Oy

InventorsHeikki SAARI, Jussi MÄKYNEN, Christer HOLMLUND, Uula KANTOJÄRVI, Jarkko Antila, Rami MANNILA

Life of this patent

Estimating the term…

Loading patent…

Abstract

An imaging spectrometer includes a Fabry-Perot interferometer and an image sensor having color-sensitive pixels. The interferometer has a first transmission peak and a second transmission peak (PEAK2). A method calibrating the spectrometer includes providing first calibration light, which has a narrow spectral peak, obtaining first detector signal values from the image sensor by coupling the first calibration light into the spectrometer when the reference spectral peak is near 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 near a second spectral position, providing second calibration light, which has a broad bandwidth, and obtaining third detector signal values from the image sensor by coupling the second calibration light into the spectrometer.

Claims12

Dependent claims

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.

5 more elements

A computer program product embodied on a non-transitory computer readable medium, comprising computer program code for determining calibration parameters of 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,

wherein the computer program code is configured to, when executed on at least one processor, cause an apparatus or a system to:
provide first calibration light, which has a reference spectral peak at an adjustable spectral position,
obtain 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,
obtain 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,
determine a first group of calibration parameters from the first detector signal values and from the second detector signal values,
provide 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,
obtain third detector signal values from the image sensor by coupling the second calibration light into the spectrometer, and
determine a second group of calibration parameters from the third detector signal values and from the first group of calibration parameters.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 14/049,636Filed 9 Oct 2013
Priority: FI FI 2012606611 Oct 2012
Published: 26 Jun 2014
Term ends: Not estimatedThe source records don’t support an estimate.

Classification9 codes

H04N 23/88
For processing colour signals: for colour balance, e.g. white-balance circuits or colour temperature control
G01J 3/0208
Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows: using focussing or collimating elements, e.g. lenses or…
G01J 3/26
Generating the spectrum; Monochromators: using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters
G01J 3/2803
Investigating the spectrum: using photoelectric array detector