Cylindrical lens based Wadsworth grating imaging spectrometer

Abstract

The invention discloses a cylindrical lens based Wadsworth grating imaging spectrometer, belongs to the spectrum technology field, and aims to solve the problems that wavelength astigmatism in a working waveband of a conventional Wadsworth spectrometer system increases along with expansion of the working waveband, spectrum curving is caused, flat image fields are not easy to realize, and the Wadsworth spectrometer system is difficult to apply to imaging spectrometers. The grating imaging spectrometer comprises a slit, a collimating lens, a concave grating and a cylindrical lens. The collimating lens is an off-axis parabolic lens, and the slit is positioned at the focal position of the collimating lens. Divergent light emitted from the slit becomes a parallel beam after passing through the collimating lens, the parallel beam enters the concave grating, and the central wavelength of an outgoing beam subjected to chromatic dispersion by the concave grating is located on the normal of the concave grating. The outgoing chromatic dispersion beam is re-focused on an image surface after passing through the cylindrical lens. The placement position and the inclination angle of the cylindrical lens between the concave grating and the image surface, and the wedge angle of the cylindrical lens need to meet some conditions.

Description

technical field [0001] The invention relates to a novel improved Wadsworth grating dispersion imaging spectrometer based on a cylindrical lens, belonging to the field of spectrum technology. Background technique [0002] The basic components of an imaging spectrometer include a slit, a collimation system, a dispersion system, a focusing system and a detector system. When designing the optical system of the imaging spectrometer, in order to achieve high-resolution spectral imaging of the slit image in a wide band, the following problems need to be solved: [0003] (1) Realize full-band astigmatism elimination as much as possible; [0004] (2) Eliminate spectral bending as much as possible, so that the image plane is a flat image field; [0005] (3) The aberration is eliminated for the angle of view corresponding to any point on the slit. [0006] The Wadsworth spectrometer system was invented very early, and it has been used to a certain extent because of its perfect conve...

AI Technical Summary

Problems solved by technology

[0007] In order to solve the problems that the astigmatism of each wavelength in the working band of the traditional Wadsworth spectrometer will gradually increase with the expansion of the working band, there is spectrum bending, it is difficult to achieve a flat image field, and it is difficult to apply to the imaging spectrometer, and provides a wide range The Wadsworth dispersive imaging spectrometer based on the cylindrical lens for band detection, by adding a cylindrical lens with a wedge angle and a certain inclination angle in the optical path, the improved system can obtain a perfect imaging effect in a wide band, which improves the performance of similar structures. Optical Imaging Performance

Images