Design And Applications Of Diffractive Optical Elements For Infrared Broad Waveband With High Efficiency

Nowadays, due to the development of fabrication technology, especiallySingle-Point Diamond Turning (SPDT), Kinoform Diffractive Optical Elements(DOEs) have been used in so many infrared optical systems. Due the efficiency ishigher than Binary optical element, Kinofrom can be used to achromat, athermalizeand relief the system. Nevertheless, the diffraction efficiency is still a major factor inthe diffractive optical element in an imaging optical system, the applicationconstraints, in particular the application of a wide spectral imaging optical system, itis necessary to study the high diffraction efficiency can be achieved in the infraredspectral width The diffractive optical element.This paper systematically studied the relevant diffractive elements relevantliterature, comparing the ordinary single-layer diffractive element, single-layer andmulti-layer diffractive elements harmonic diffraction efficiency diffractive elements,according to the scalar diffraction theory and ray tracing methods carried outrelevant research. The main work is as follows:Firstly, we study the relevant literature on the diffraction efficiency of thediffractive optical element, according to the literature summarized the followingconclusions: Ordinary single diffraction element is difficult to achieve highdiffraction efficiency spectral width, single harmonic diffractive elements can be in multiple harmonic100%at the wavelength of the diffraction efficiency, and theseharmonics have the same focal length, the diffractive element with a double air gapat a small incident angle can be achieved when a high diffraction efficiency within awide band, it will be replaced with another material for forming an air gap theso-called three elements can eliminate the influence of the diffraction angle ofincidence on the diffraction efficiency.Secondly, it discusses with double diffractive optical element air gap of thematerial selection and design wavelength selection problem, according to thefindings to design a3~5μm infrared wave and long-wave diffraction efficiency of8~14μm integral bandwidth greater than96%of ZnS/Air/ZnSe double diffractionelement, a simple structure and design, a good image quality dual band infrareddiffractive element designed by double total aperture, the confocal optical systemside. Meanwhile the paper discusses the impact of the incident angle of diffractionefficiency, methods of designing three diffractive element.Finally, we studied the effect of temperature on diffractive elements, includingthe impact on its diffraction efficiency, aberration, etc.. Athermal optical systemaccording to the theory, discusses the use of high diffraction efficiency diffractiveelements athermal infrared system design methods and the actual optical system wasathermal design.In this paper, through the design and application of research on diffractiveoptical element design using dual wavelength double diffractive optical elementsdesign method of infrared color wide-band high diffraction efficiency of thediffractive optical elements, while taking advantage of the design of ZnS/Air/ZnSedouble diffractive optical component design infrared color wide-band highdiffraction efficiency diffractive optical systems.