Teknologian Tutkimuskeskus Vtt

Teknologian Tutkimuskeskus Vtt Oy

Teknologian Tutkimeskeskus Vtt

Rami Mannila

Heikki Saari

Christer Holmlund

Pekka Teppola

Uula Kantojarvi

Antti Lamminpaa

Jarkko Antila

Jussi Mäkynen

Uula Kantojärvi

Antti LamminpÄÄ

Device and method for combining light beams

The invention relates to a system and a method for optical measurement of a target, wherein the target is illuminated, either actively illuminated, reflecting ambient light, or self illuminating, and a measurement light beam received from the target or through it is detected. The prior art optical measurement systems generally include mechanical filter wheels and photomultiplier tubes, which cause the equipment to be expensive, large-sized and often not sufficiently accurate and stable. The objective of the invention is achieved with a solution, in which the illuminating light beam and/or measurement light beam is led through a Fabry-Perot interferometeror a set of two or more Fabry-Perot Interferometers, and the Fabry-Perot interferometer or a set of two or more Fabry-Perot Interferometersis controlled into different modes during the measurement of a single target. The invention can be applied inoptical measurements where, for example, reflectance, absorption of fluorescence of the target is measured.

System and method for optical measurement of a target

The invention relates to a system and a method for optical measurement of a target, wherein the target is illuminated, either actively illuminated, reflecting ambient light, or self illuminating, and a measurement light beam received from the target or through it is detected. The prior art optical measurement systems generally include mechanical filter wheels and photomultiplier tubes, which cause the equipment to be expensive, large-sized and often not sufficiently accurate and stable. The objective of the invention is achieved with a solution, in which the illuminating light beam and/or measurement light beam is led through a Fabry-Perot interferometer or a set of two or more Fabry-Perot Interferometers, and the Fabry-Perot interferometer or a set of two or more Fabry-Perot Interferometers is controlled into different modes during the measurement of a single target. The invention can be applied in optical measurements where, for example, reflectance, absorption of fluorescence of the target is measured.

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.

Method for determining calibration parameters for a spectrometer

Growing community of inventors

Vtt, Finland

Rami Mannila