In order to improve the light utilization rate of the existing outdoor basketball court lighting and reduce the glare value, this paper designs a deflected lighting scheme to reduce the light exposure to the outside of the field. Through optical analysis of different lighting schemes, the reasons for the low utilization rate of light are found, and the deflected light design is carried out to make the light illuminate the inside of the venue in a concentrated manner. DIALux is used for simulation analysis of the overall scheme: the overall illuminance uniformity reaches 0. 85, and the measured glare value GR maximum is 29, which is far less than the outdoor stadium glare required value of 50. The uniformity and glare control can meet the needs of various competitions. The calculated light utilization rate of 75% is far greater than the 52% of the existing lighting scheme. Compared with the existing lighting scheme, the energy-saving effect is significant.

近年来,由于芯片荒,中国的数字电视机顶盒行业受到了不小的冲击.本文以VC 6.0为开发平台,用C语言进行程序设计,实现高清数字电视机顶盒软件应用层UI菜单,分析中间层数字视频广播PSI节目特定信息和SI业务信息,分离底层接口函数,实现可以快速移植到具体高清数字电视机顶盒硬件平台的软件中间件.测试结果表明,该中间件能移植到具体硬件平台,快速实现高清数字电视机顶盒功能,提高开发效率.

Based on the cross-spectral density and the unified theory of coherent and polarization, the intensity expression of the Radially Polarized Partially Coherent Spiral Bessel Beam (RPPCSBB) can be significantly deduced. The propagation properties of the beam were also investigated. The RPPCSBB transmits in a spiral path with a fixed distance in free space by the theoretical analysis and numerical calculation. During the transmission, the beam gradually evolves from a spiraling hollow beam to a spiraling Gaussian beam, and the transmission distance is related to the coherence length. The corresponding beam polarization angle and degree are also related to the spiral radius and the coherence length, and the polarization degree relates to the transmission distance. However, the coherence length, transmission distance, and the spiral radius do not affect the distribution of the beam polarization ellipticity.

the selection of teaching mode is related to the improvement of teaching quality. In order to improve the quality of teaching and promote the transformation of teaching results, combined with big data statistical analysis method, a choosing teaching method is proposed based on big data's analysis, which constructs the statistical analysis model of teaching mode selection by descriptive statistical analysis method, and extracts the quantity of characteristic information that reflects the optimization of teaching method selection. The big data analysis model based on fuzzy C-means clustering is used to evaluate the performance of teaching methods, and the method of segmental sample detection is used to carry out regression analysis to realize the sample fitting of teaching method selection. The mathematical model of teaching mode selection is designed through the sample fitting result, and the statistical mathematical model based on big data's teaching mode selection is constructed. The simulation results show that the method is used to select the teaching method; it can effectively extract the regular characteristic quantity, which reflects the teaching performance, realizes the association rule mining of the choice of teaching method. The teaching mode is selected according to the result of big data mining and statistical analysis, improving the teaching quality, and promoting the reform of teaching methods.

Based on the generalized Huygens-Fresnel diffraction theory, the intensity expression of the radially polarized spiral Bessel beam is derived. The transmission characteristics, the change of the polarization state and self-reconstruction characteristics of the beam during transmission are studied. It is found that, by the theoretical analysis and numerical calculation, when the radially polarized spiral Bessel beam is transmitted in free space, the beam is spirally transmitted around the optical axis in the form of a hollow beam and the divergence angle of the beam is zero in a certain transmission region. In addition, the characteristics of radial polarization are maintained during the transmission process. The off-axis spiral transmission characteristic is always maintained and the energy conservation law is followed in the self-reconstruction process of the beam. As the transmission distance increases, the energy originally disappeared in the occlusion region is gradually diffracted to the opposite position of the obstacle occlusion area.

The innovative education is based on the development of innovative thinking and the training of innovative talents as the basic value orientation. It is necessary to recognize the problems encountered in innovative education, explore new ways and methods of innovative education with new ideas, and strive to implement innovative education in teaching. Tabu search algorithm is a combined optimization algorithm and an extension of local search algorithm. It is a successful application of artificial intelligence in combinatorial optimization algorithm, which is characterized by the use of tabu techniques. The taboo in the real sense is the prohibition of duplication of the previous work. Tabu search algorithm uses a tabu table to record the local best points which have arrived. In the next search, tabu list information is used to search these points no longer or selectively. In the course of teaching, the students' innovative ability is constantly improved so the comprehensive learning ability of the students will be improved.

In this paper, the self-reconstruction property of astigmatic Bessel beam is studied experimentally and theoretically. Based on the Fresnel diffraction integral theory and Babinet principle, the general expression of the intensity distribution of astigmatic Bessel beams passing through a circular obstacle is derived. The cross-section light intensity at transmission distance of, 10, 30, and 80 mm after astigmatism of the astigmatic Bessel beam are occluded by circular obstacles. The self-reconstruction process of the light field is observed and verified by using an specially designed experimental setup. In the experiment, we choose He-Ne laser as a light source, collimate and expand the beam through a telescope system, and a zero-order astigmatic Bessel beam is generated by a beam vertically incident on the tilted axicon after the diaphragm. A circular obstacle with a radius of 0.2 mm is placed at a distance of 200 mm behind the axicon. Finally, the cross-section intensities at different distances are observed and recorded by a microscope. The experimental phenomena are in good agreement with the theoretical prediction. The results show that the reconstruction of the zero-order astigmatic Bessel beams will occur after passing through the on-axis and off-axis obstacles. And as the transmission distance increases, the outer contour size of the astigmatic Bessel beam becomes larger, and the number of central spot arrays increases, and the complete beam is gradually reconstructed. Particularly, this feature is different from the behavior of the non-diffracting Bessel beam, which maintains the light field unchanged during transmission and has a single central spot. It is expected to be applied to multi-layer multi-particle control. And a new optical property is discovered in the experiments: the reconstruction speed of the beam in the horizontal and vertical direction are not consistent in the reconstruction process, and there is a certain speed difference. Further, we add a spiral phase plate between the diaphragm and the axicon to produce a high-order astigmatic Bessel beam. And it is verified that the high-order astigmatism Bessel beam has the same self-reconstruction characteristics after being shielded by obstacles. Compared with the zero-order aperture system, the high-order beam can not only expand the operating range, but also use the orbital angular momentum carried by the beam to achieve light rotation, which makes the particle manipulation more flexible. The research proves the self-reconstruction characteristics of astigmatic Bessel beams theoretically and experimentally, and broadens the research range of astigmatic Bessel beams. The research results have practical significance and application value in the field of optical micro-manipulation.

基于Collins公式,导出角向偏振螺旋贝塞尔光束的光场表达式,研究该光束的传输特性及暗核位置对光束偏振态的影响.通过理论分析和数值计算发现:角向偏振螺旋贝塞尔光束在一定传输区域内是以空心光束绕光轴做离轴螺旋传输,并且光束的发散角为0;光束的偏振态随着暗核位置的移动而发生整体偏移.

This paper introduces the research progress of caustic beams at home and abroad.The self-healing process of two basic caustic beams based on spectral phase classification is analyzed.The formation and trans-mission properties of two typical beams of lip-shaped caustic beam and Pearcey caustic beam are summarized in detail,and the prospect of their application is prospected.The results of the articles show that compared with the Bessel non-diffracting beam,the caustic beam is a special self-healing beam and has its unique advantages in special fields such as micromanipulation,topological charge detection and snow blower.

Pearcey beam was obtained by designing a simple optical element-parabolic slit aperture.Based on the generalized Huygens-Fresnel diffraction integral in the spatial domain,the Pearcey beam expression of the system was derived.Numerical simulations and experiments verify the generation of Pearcey beams.At the same time,the self-focusing characteristics of the Pearcey beam were studied,and the effect of the focal distance of parabolic silt aperture on the focal spot was discussed.The experimental results show that the size of the self-focucal spot was consistent with the numerical simulation.The results provide theoretical and experimental basis for the Pearcey beam for optical trapping.

To study the distribution of graphene conductivity, big data was applied. The basic structure and properties of graphene were introduced. The changes of the electrical conductivity and dielectric constant of graphene with the frequency of light source, Fermi level, temperature and other parameters were analyzed. An analytical model for the study of the conductivity of graphene was established. The results showed that the conductivity could be adjusted by changing the doping level of graphene. Therefore, graphene has potential applications in the fields of sensing and spectroscopy.

A new method is introduced by using the cross-spectral density function to describe the caustics beam, which is extended from fully coherent cases to the field of partially coherent cases for the first time. And the propagation formula of caustics beam is derived in the free space combined with the Fresnel Kirchhoff diffraction integral theroy. The influence of astigmatism introduced by tilted axicon at various inclination angles on partially coherent caustic beam with respect to the propagation axis was studied theoretically and experimentally. Furthermore, the partially coherent caustics beam is invested that is effected by the field coherence on the partially coherent caustic beam. Results show that the intensity contrast ratio between light focus and the surrounding dark regions can be reduced with the decrease of the spatial coherent lengths.

The principle and design method of polymer optical fiber bundle (POFB) lens coupler with high-power light emitting diode ( LED) as light source is studied. Based on energy compensation and coordinate iteration method, a free-form lens coupler with uniform energy distribution is designed. The lens coupler consists of two refraction free-form surfaces, two reflection free-form surfaces and a circular cylindrical lens surface. The small divergence angle of the modified Lambertian high-power LED beam is quasi-uniformly distributed on the end face of POFB through refractive free-form surface. The reflection free-form surface reallocates the energy of large divergence angle of LED beam as compensation to improve the target surface illumination uniformity. Lens coupler is designed and optimized for illumination uniformity and effective light utilization of the end face of the fiber bundle. The results of optical simulation show that when the 3535 LED is used as the light source, the designed coupler can make the illumination uniformity of the 20 x 20 polymer fiber bundle with the diameter of 0.5 mm reach 92% and effective light utilization reach 71%.

The LED caustic beam is generated by LED light source. A method of using cross-spectral density function and superposition of multi-spectral is proposed to calculate the intensity distribution of the LED caustic beam through the axicon. The influence of parameters such as dispersion on caustic beam is theoretically and experimentally demonstrated. The influence of the transmission distance on the LED caustic beam is further studied. It is found that the outer contour of the caustic beam becomes larger and the central light spots symmetrically split into light spot array as the transmission distance increases. Meanwhile, the central intensity decreases correspondingly, and the contrast of the light spot array decreases gradually. It will evolve into an approximately hollow beam eventually. This research results enrich the connotation of caustic beam, and provide a theoretical basis and experimental evidence for the practical application of LED caustic beam.

The principle of generating the spiral Bessel beam is theoretically analyzed. Based on the cross-spectral density function of Gaussian-Shell model and the theory of cross-spectral density propagation, the expression of partially coherent spiral Bessel beam is derived. The propagation characteristics of partially coherent spiral Bessel beam arc studied and the influence of coherence on its transmission characteristics is analyzed. The results show that with the increase of transmission distance, the contrast of beam intensity distribution of beam cross section decreases, and the distribution of light field changes from the Bessel type to the Gaussian type. However, the beam still maintains the self-acceleration property. For the high-order beam, a phenomenon of dark core fading can be found easily and the fading distance of the dark core increases with the increasing of the beam order. With the decreasing of the coherent length, the distribution of Bessel light field decreases gradually, and the non-diffraction distance of the beam is shortened. Moreover, the influence of light field regulation on the beam is also discussed, which includes the parameter setting of the hologram and the adjustment of the coherence of the light field.

The Mathieu beam produced by partially coherent light was studied theoretically and experimentally, based on Fresnel diffraction theory and Fourier transform. The intensity expression of the Mathieu beam was derived with sampling theory and dispersion formula. The section intensity distribution of the Mathieu beam at different propagation distances was simulated. And the experiment was designed to verify the simulation results. We would choose multi-wavelength blue LED as the light source in the the experiment. The Mathieu beam would be obtained using a axicon and a film with an elliptical aperture. Both simulated and experimental results show that partially coherent light can produce Mathieu beams. The results provide a theory evidence for extending the application range of Mathieu beam.