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The diffractive optical elements, with the negative dispersive characteristic and the random phase distributing to realize random phase modulation for wave-front, are not only helpful to simplify the optical system, but also improve the image quality, while putting it into the optical system. It can decrease the element numbers of the system and obtain a compact configuration that introducing diffractive optical element into the design of eyepiece. A hybrid diffractive-refractive wide-angle eyepiece, with a big exit pupil distance, is designed by using the Code V Optical Design Software. The features of the wide-angle eyepiece are 30mm effective focal length, 60°whole field-of-view (FOV), 30mm exit pupil distance and 6mm exit pupil diameter, and which consists of four lens and two diffractive elements. From the result of design, the MTF in the center field of the wide-angle eyepiece is over 0.55at 60lp/mm, at the same time, the MTFs in all fields are over 0.3 at 50lp/mm, which show that this wide-angle eyepiece has a great image quality.

Optical lenses act as the important methods for acquire the image information is applied increasingly board ,In accordance with the application environment that require content the precision and the force environment adaptation yet more power, so it is necessary that research on the adaption ability to the big level vibration and shock. In order to stand the bitter force environment put to use the centering assembly technology to ensure the image quality of the optical system. Design the different damping coefficient rubber-bearing isolation that assimilate the big level shock energy. At first, by the Pro/e software establish the three-dimensional model and use the ANSYS software simulate and analysis the result of the design. We want to apple the Sigfit software to simulate the effect that the vibration and shock affect on the MTF of the optical system. After optimize the design theory so as to attain the optimized result. By the experiment test the lenses about the accommodate ability, the result which can meet the shock of5000g.and 20g random vibration, camera can work effectively. This kind of design technology is mature and reliable and live through the examination under all kinds of environment, this design method is provided the reference for the design and development of optical mechanism production.

Optical equipments especially those for aerospace application are expected to work over a wide temperature range. The change of temperature could cause the refractive index change of infrared glass elements. Furthermore, it would lead to the defocus of the image surface and the performance degradation, so the method of temperature compensation must be adopted, which could make sure that optical system would adapt to the change of ambient temperature. A method of temperature compensation with mechanical passive compensation is briefly described, and an example is also given. The quality of image could be optimized through mechanical passive compensation,depending on the differences of metal and non-metallic thermal expansion coefficient. The results show that the optical system works stablely in the designed temperature range. It is of great importance to the athermalisation design of infrared optical system.

Due to the possession of advantages of passivity working mode, good disguise, and easy observation, infrared systems are used in a wide variety of applications. This paper using 640×480 uncooled detector designed a long-wave scan optical system with large field and large aperture working at 8.0μm～12μm, the Pixel Dimensions of the detector is 30μm. The F number of this system is 1.4 and focal length is 17mm, FOV is 63.6°, which extended to 143° by adopting dual-wedge prism rotating, the paper also given the extended field theory by the dual-wedge prism. Because there are a limited number of lens materials used in LWIR spectral bands, Germanium material and three aspheric surfaces were adopted to balance sphere aberrations and chromatic aberration. All above mentioned are intending to ensure the system has good imaging quality. The results show that the optical performance approximates to the diffraction limit and the design has better achromatic performance. The modulation transfer function (MTF) is above 0.5 at spatial frequency of 20lp/mm, energy concentration ratio is greater than 70% within the sensing element of the detector and Root Mean Square (RMS) value of spot diameter is smaller than the Pixel Dimensions. The system has advantages of simple structure, large aperture, high image quality etc.

The paper introduces a kind of super relative aperture condenser which has the strcuture of spherical Fresnel surface with catadioptric projection optical system, it would improve the condensing capacity and light efficiency substantially. The condenser is composed of two sections with a center and an outer ring, the center region adopted the basic structure of the Fresnel lens with the Fresnel of laplace domain continuous curve transmission type, and the outer structure which achieve light collimating or focusing by total reflection is stepped. The paperstudies the parameter and alforithm of this catadioptric dual-zone Fresnel condenser and gives the surface data of total reflection region. Based on the method of establishing the entity model, we design a set of lens with the relative aperture F=0.3, simulate the condensing ability of the lens by the simulation software, and verify that the lens have a very good effect on focusing.