The Design Of Telescopic Opcial System With Gradient Index Element

Imaging spectrometers,gradually developing from optical remote sensing, are new remote sensing instruments could received both spatial and spectral information from the object of interest at same time, which has important applications in the military field and civilian fields. Pre-telescope systems undertake a important role in imaging of the target scene, it is an indispensable part of the instrument to collect light energy and information data. With the development of imaging spectrometer, the image quality of pre-telescope imaging systems are also required to improve.Due to its medium refractive index changed in a special law, a gradient index lens have some optical properties that never show in a uniform dielectric lens. The gradient index lens used in the pre-telescopic imaging systems can enhance the image quality of the system, increasing the field of view of the system, and simplifying the system,which make optical system lightweight.The typical structure and the imaging characteristics of the pre-imaging system is discussed in this article. Axial gradient index lens' aberration characteristics, based on graded-index optical design theory, is analysed. The design method for axial gradient index lens is described,and a axial gradient index lens which comply with the requirements of the system is designed. Finally, a long focal length, wide spectrum telephoto lens is designed. The system uses folded structure with the axial gradient index components combined and improve the image quality.There are only two glasses in the lens to keep it lightly.