Gas visualizing methods and systems with birefringent polarization interferometer

US10612975B2 · kind B2 · utility

Assignee

• FLIR Systems AB · SE

Inventors

• Jonas Sandsten · Lomma, SE
• Joakim Sjunnebo · Cambridge, GB

Key dates

• Filing date: Dec 6, 2017
• Grant date: Apr 7, 2020
• Expiry date: Dec 6, 2037

Classification

• Technology area (CPC G): Physics
• CPC primary: G01J2003/2826
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Systems and methods disclosed herein provide for gas imaging. A gas imaging system comprises a lenslet array configured to receive thermal radiation from a scene and transmit a plurality of substantially identical sub-images of the thermal radiation; a birefringent polarization interferometer configured to generate an optical path difference for each ray of the plurality of sub-images based on a respective position of each ray entering the BPI, the optical path differences combining to form an interference fringe pattern; and an infrared focal plane array configured to capture a thermal image of the plurality of sub-images modulated by the interference fringe pattern due to the optical path differences through the BPI. The captured thermal image may represent a plurality of interferogram sample points of the thermal radiation from the scene, and may be used to construct a plurality of hyperspectral images of the thermal radiation from the scene.