Long-wave infrared imaging spectrometer optical system based on SAGNAC interferometer

Abstract

The invention discloses a long-wave infrared imaging spectrometer optical system based on an SAGNAC interferometer, and the system comprises a scanning reflection system which is used for scanning a field of view to obtain an interference image of a full field of view; the front group telescopic system is used for compressing target radiation energy into small-caliber parallel light beams so as to prevent the size of a rear interference system from being too large; the SAGNAC interferometer optical system consists of a beam splitter and two plane mirrors, is positioned between the front group of telescopic system and the rear group of imaging system, and divides target radiation energy into two coherent light beams which are parallel to each other, and interference fringes are formed on an image surface after the two coherent light beams pass through the rear group of imaging system due to different optical path differences of the two coherent light beams in different fields of view; and the rear imaging system is used for imaging two beams of parallel light obtained by light splitting of the SAGNAC interferometer onto a focal plane of an infrared detector, and two-dimensional space information and real-time spectral information of the target can be obtained on the detector at the same time.

Description

technical field [0001] The invention relates to the technical field of optical systems of imaging spectrometers, in particular to an optical system of long-wave infrared imaging spectrometers based on a SAGNAC interferometer. Background technique [0002] The long-wave infrared imaging spectrometer is an instrument used to obtain the two-dimensional spatial information and one-dimensional spectral information of the target's own long-wave infrared radiation. The optical system is mainly composed of a front objective lens, a spectroscopic system, an imaging objective lens and a detector. The spectral data and spatial data of the spectrometer are mainly used in the fields of high-performance photoelectric reconnaissance, photoelectric countermeasures, chemical agent telemetry, and landmine detection. [0003] Infrared imaging spectrometers can be divided into three types: dispersion type, interference type and filter type according to the different ways of splitting light. Gr...

AI Technical Summary

Problems solved by technology

The disadvantage of this structure is that it has moving parts, and its anti-interference ability to vibration and other factors is poor; and the scanning time of the moving mirror is long, and real-time and fast measurement cannot be performed. Before use, the moving mirror needs to be calibrated to ensure that the mirror It is in the position of zero optical path difference; it has high requirements for the use environment, and is often used in the laboratory environment, which is difficult to meet the needs of outdoor use such as rapid detection in complex environments, high-altitude and high-speed monitoring, etc.

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