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Design of a solar-blind ultraviolet detection system

Solar-blind region of UV wave waveband, which is from 240nm to 280nm, is absorbed by atmosphere seriously.
This feature can ensure solar-blind ultraviolet(UV) optical system is not affected by natural and artificial light sources. In
this paper, an optical system based in the solar-blind spectrum region is designed to realize UV missile warning.
System structure is simplified and image quality is improved by using aspheric surfaces and binary optical elements.
In order to increase the detection range, the field of view is increased to 50°. The focal length of system is 30mm and UV
CCD PIXIS 2048BUV is selected as the detector with effective imaging area 27.6mm×27.6mm and pixel size
13.5μm×13.5μm. From the diagram of diffraction encircled energy, more than 85% of the light energy for each field of
view is received within a pixel size. The spot diagram for each field of view is smaller than a single pixel size. The image
quality of the system has characteristics of high energy concentration and uniform illumination on image plane. This
system is suitable for both military and civil applications.