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Large aperture optical detection equipment has the shaky with its elevation angle changing when the support point of primary mirror changes. This paper studies how to compensate the measuring errors caused by the primary mirror shaking and to improve the static measuring accuracy of the large aperture optical detection equipment. Firstly, the supporting structure and mechanic model of a 1m diameter telescope were presented. Then, a new error compensation method for the large aperture telescope was proposed based on the analysis of the traditional three axis error compensation method and spherical harmonic error compensation method. The calibration experiments for the optical detection equipment was performed. By selecting 32 stars whose refractions had been revised, the error of each system was solved to obtain the primary mirror shaking error and the three axis difference. As comparison with the traditional error compensation method, it shows that the static measurement accuracy of the telescope has increased from 15.4 "to 2.5 after the shaking error of the primary mirror is compensated. It concludes that the physical meaning of this method is clear, and each error component has good repeatability. It improves the static precision of large aperture telescope by compensating the shaking errors of primary mirror.

To acquire the spatial frequency response of the interferometer,the testing method on instrument transfer function( ITF) of interferometer was researched. First,the theoretical calculation model of instrument transfer function of imaging system was established,and the testing model of Fizeau interferometer was simulated via lens design program. Then the theoretical value was calculated and anaysed. Comparing ITF based on the method of sine phase plate with the theoretical ITF,the error is less than 0. 6%,and this method is proved to be feasible via the simulation of the optical design program.

Graphene鄄ZnO nanocomposites and pure ZnO samples were prepared by solvothermal method under the same conditions. The morphology and structure of nanocomposites were character鄄 ized by SEM, TEM, Raman and infrared spectroscopy. The results show that ZnO nanoparticles have dispersed on a few layers graphene. Compared with the morphology of graphene鄄ZnO nanocom鄄 posites, it is found that pure ZnO can grow into a preferred orientation of hexagonal structure, while ZnO aggregates into sphere in the presence of graphene which is attributed to the graphene hindered the preferred orientation of ZnO growth. From the PL spectra, the ultraviolet emission peak intensity of graphene鄄ZnO is stronger than that of pure ZnO, and accompanied by blue shift phenomenon. The difference of ultraviolet photoluminescence between ZnO and graphene鄄ZnO comes from the differ鄄 ence of morphology and the plasma effect of grapheme, while the plasma effect of graphene plays a key role.

With advantages of high sensitivity and more information,coherent micro-doppler laser was especially suitable for the detection of moving targets,identification of objects' characteristics,etc.The influence of phase fluctuation in the mode field(phase noise) on velocity accuracy was discussed in two aspects including linewidth and detection distance.The experimental results validated the phase noise influence on micro-doppler detection,and a new method resolving the above problems,which called range-compensated method,was proposed.In the experimental system,the laser source was monolithic non-planar ring laser with the wavelength of 1.06 μm.The micro-doppler frequency was observed by heterodyne detection,which was processed by means of time-frequency analysis.Minimum detecting velocity of the system is 0.5 mm/s,velocity resolution reaches a level of mm/s,and frequency resolution reaches a level of kHz,when the detection distance is 11 km.The results laid an experimental foundation for the practical application of micro-Doppler ladar.

Regarding TI's DSP chip TMS320F2812 as the main chip,a kind of LRG(Laser Rang-Gating) imaging system based on the DSP is designed.The controller has LCD display and key setting function.The system status and parameters can be displayed on the LCD.The function and hardware structure of the controller,and software flow design has been given.The practice proved that the controller has the advantages of simple structure,delay time precision and real time.The controller satisfied perfectly the laser active illuminated imaging system.

The Light Emitting Diode model is presented based on the scattering theory.Taking the influence of low dose ionization radiation damage into consideration,the model of the relationship between device scattering factors and radiation damage is introduced.Over a wide range of input current,the electrical characteristics of devices are meassured for different ionization radiation situations.The experimental results agree well with the proposed models.After the analysis of the experimental results and the above-mentioned models,the relationship between low dose ionization radiation damage and Light Emitting Diode performance degradation is studied.It is proved that with increasing electron density in recombination center,the interface trap density and scattering probability increase slightly,which leads to slight degradation of I-V and L-V characteristics in Light Emitting Diode.Because heavy particle radiation can cause displacement effect directly,which leads to significant increase of interface trap density,heavy particle radiation has much more influence on the performance of Light Emitting Diode than ionization radiation.

With a movable quadrupole magnetic trap (QMT) generated by two pairs of partly-overlapped magneto-optical trap (MOT) and transfer coils, a highly efficient transport of cold87Rb atoms to the atom chip surface is realized. By the QMT movable means of linearly increasing the current in the transfer coils but simultaneously keeping the current in the MOT coils constant, the velocity profile of the moving trap is Blackman-type-like. With this QMT movable scheme, the cold atoms are transferred to the atom chip surface from the MOT center. In the transfer process, the cold atom temperature is increased by about 30 μK, and the transfer efficiency is above 90%. This system provides an appropriate cold atoms source for the atom chip interferometer and also can be used to investigate the interaction between atom and chip surface. ? 2016, Chinese Lasers Press. All right reserved.

The coupling between solar light radiation and laser rod medium in a solar pumped laser affects the efficiency of the laser. To optimize the pumping system, simulation of the two-stage pumping system with a Fresnel lens and conic pumping cavity is carried out with Tracepro software. According to the power density distribution along the axis at focal place of the Fresnel lens, the diameter and position of the pumping cavity window and the distance of the window from the Fresnel lens are optimized. The power density distributions along the laser rod axis of different cavity lengths and different cavity tapers are also analyzed. The optimal structure of taper cavity is obtained. The mirror relecting cavity and ceramic cavity are introduced in detail.