COMPACT, CATADIOPTRIC, AND ATHERMAL IMAGING SPECTROMETER

摘要

A compact, catadioptric, and athermal imaging spectrometer. A telecentric light ray (1) emitted from a slit (2) is folded or refracted by an object side prism (3) to enter a plano-convex lens (4). After being refracted by the plano-convex lens (4) and a meniscus lens (5) and being refracted and reflected by a thick reflex lens (6), said telecentric light ray is emitted onto a convex grating (7) in the form of a gathered light beam, and after said light beam is diffracted, spectral division is implemented. Diverging light beams are sequentially refracted and reflected by the thick reflex lens (6) and refracted by the meniscus lens (5) and the plano-convex lens (4) to enter an image side prism (8). After being folded or refracted and filtered, said diverging light beams are imaged on a focal plane (10) to implement spectral imaging. The spectrometer uses an Offner device-based totally immersed catadioptric light path, features a compact structure, and greatly increases a relative pore size of an imaging spectrometer. A meniscus lens having a high refractive index is used to implement long-lit spectral imaging. The thermal expansion coefficients of materials of refractive elements are preferably selected, such that the imaging spectrometer has stable quality of image within a large range of temperature, thereby implementing an athermal effect. The spectrometer is suitable for hyperspectral remote sensing applications requiring a large field of view, high signal-to-noise ratio, and high temperature adaptability.