| To meet the requirements of the lighter, smaller and high-performance optical equipments in the modern society, the diffractive optical elements (DOEs) have been paid much more attention. The harmonic diffractive optical elements (HDEs) are one kind of special DOEs. Their aberrations characteristics are similar to the normal DOEs, but their dispersion characteristics are between the refractive lens and the normal DOEs. This unique characteristic of HDEs has many special applications. For example, used as a lens, HDEs can achieve spectroscopy and imaging simultaneously in multiple harmonic wave-bands, which makes it possible to achieve the multi-band common-path and design the small-oriented diffractive-refractive optical systems. To make use of the special feature of HDE to simultaneously complete the dispersion and imaging, the HDE-based imaging spectroscopy is among the emerging multi-band imaging spectrometer technologies, which has many advantages such as spectral high resolution, compact structure, light weight, durable, cost-effective, easy to achieve the advantages of small size and light weight. Based on the diffractive optics and infrared optics, this dissertation is to study the performance of MWIR/LWIR Dual-band Stare Hyper spectral Imaging System Based on HDE. The prototype of MWIR/LWIR Dual-band Stare Hyper spectral Imaging System Based on HDE is designed and constructed; the corresponding experiments are carried out; and the spectral images of the experimental goals are got through this prototype. The results obtained with this prototype are identical with those theoretical predictions, which corroborates the effectiveness and feasibility of the HDEs in the spectral imaging system.In chapter one, the development history and applications of DOEs, the applications and prospects of MWIR/LWIR Dual-band systems are reviewed. The basic principles and the corresponding equipment types of the typical imaging spectrometer are summarized. The HDE-based staring hyper spectral imaging technology is a spectro-tomographic technique which integrates over a narrowband of the image cube which is a new concept of imaging spectrometer. So the general research direction and the basic research scheme are determined. In chapter two, the dispersion and imaging characteristics are introduced. It is pointed out the HDE is a special kind of DOE with unique dispersion characteristics. Chapter three describs in detail the theoretical knowledge of the HDE-based staring hyper spectral imaging technology, complets the derivation of the spectral resolution and line resolution, then gives their concrete expression. Two different kinds of the MWIR/LWIR dual-band imaging spectrometer system based on HDE are designed in Chapter four. The aberration theory and design process are described, and then the influence to the imaging quality of the system due to the fabrication errors of HDEs is analyzed. One high-resolution systems with a resolution of 24nm at wavelengthλ= 10 m and one medium-resolution system with a resolution of 72nm design at the wavelengthλ=8.5 m are designed. Finally the medium resolution system is chosen for the optical system of the prototype. Chapter five describs in detail the calibration theory of the MWIR/LWIR dual-band imaging spectrometer system based on the HDE and gives the calibration method. In Chapter six, the work principles of the prototype are presented, the experimental tests are described. The results obtained have good agreements with the theoretical predictions, which verifys the prototype's usability. Finally, the work is summarized and suggestions for future work are presented in Chapter Seven.In conclusion, the HDE-based hyper spectral imaging technology is feasible in theory and engineering. Operating at ultraviolet, visible, near infrared or thermal infrared wavelengths, binary optic imaging spectrometer is a practical image spectrometer for surveillance, remote sensing, medical imaging, law enforcement and environmental monitoring.
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