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In this paper, a resonator coupled with a branched straight waveguide and an open square ring is constructed. Based on the Fano resonance principle of Metal-Insulator-Metal (MIM) structure, the dependence of the transmission lines on the parameters of the resonant cavity is analyzed by finite element method. When the space between the open square ring and the straight waveguide is G=90 nm and the branch height H=140nm, the dual Fano resonance transmission peaks with the central wavelength of λ=746nm and 1521nm with anti-symmetric lines can be generated in the resonator structure. The results showed that the peak value of left resonance increases with the increase of H with the maximum value at H=140nm, and then decreases slowly with the increase of H until it disappeared. Though the height of the right resonance peak is almost unaffected by H, the transmission valleys are most affected by H. With the increase of H, the transmission valleys of the branch resonant cavity move to the direction of long wavelength, while the two transmission valleys on the right basically remain unchanged. When H = 210 nm, the left Fano resonance disappears completely, leaving only the resonance on the right, and the resonance peak remains basically unchanged. Parametric scanning was set to observe the changes of Fano resonance. The optimal parameters were set between 1500 nm and 1700 nm, and the resonant coupling cavity could be used as a refractive index sensor with sensitivity of about 1496 nm/RIU and figure of merit of 60.1. This structure can provide effective basis for nanoscale refractive index sensor design. [ABSTRACT FROM AUTHOR]

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Microelectronics technology has enabled electronic devices from discrete to integrated, bringing exponential improvements in cost, reliability, power consumption, volume and other aspects for decades, which is the key to the wide application of electronic information technology. Currently, electronic information technology is facing bottlenecks such as bandwidth and energy consumption, and Moore’s Law is struggling. As another major carrier of information, photons have characteristics such as high bandwidth, high speed, low power consumption, and high parallelism. The continued progress of information technology must rely more on photons. However, the cost, reliability, and scale productivity of photonic devices lag behind the electronic devices. Therefore, based on the historical experience of the development of electronic devices, we propose the " microelectronization" of optoelectronics, emphasizing that optoelectronics take " integration" as the development track and " photoelectric fusion" as the development direction.Taking integration as the development track is to emphasize that optoelectronics should learn from microelectronics in order to meet the requirements of modern information systems for devices. The integrated development of optoelectronics has three main characteristics: the chip platform basing on silicon; the steady increase in integration scale; and the evolution of production mode towards fabless.Taking photoelectric integration as the development direction, it emphasizes the necessity of the combination of optoelectronics and microelectronics, and jointly solve the challenges of bandwidth, rate, power consumption and other challenges currently faced by information technology through device integration and function integration of the two, so as to meet the requirements of digital twins, metaverse and other applications. Photoelectronic fusion mainly has two levels: chip and system, involving monolithic optoelectronic integration, Co Packaged Optics (CPO), hybrid optoelectronic integration, device disaggregation, photoelectric hybrid computing, etc.The " microelectronization" of optoelectronics is not only a technological development guide, but also will have a significant impact on the information optoelectronics industry. The article have conducted open-minded thinking from the perspectives of market, competition, enterprises, products, etc., and pointed out that it may lead to industry reshaping.The " microelectronization" of the development of information optoelectronics is an objective requirement for the continued advancement of information technology. On the one hand, photons are being generalized from transmission technology to ubiquitous connection technology in the entire Information Communications Technology (ICT) domain, from the ground to the ocean and space at the macroscale, and from the shelf and board to the package, and chip at the microscale. On the other hand, photons will be generalized from bandwidth providing technology to a basic hardware technology for the entire ICT domain, from transmission and connection to complex functional domains such as computation, processing, and routing. The " microelectronization" of optoelectronics will enable photons not only have the potential but also the ability to fully utilize their advantages to support the continued progress of the information technology.

In order to investigate the effect of the thickness of the perovskite quantum dots light-emitting layer on the electro-optical conversion efficiency of perovskite quantum dot light-emitting diodes (PeLEDs), the cesium lead bromide (CsPbBr3) perovskite quantum dots were synthesized by ligand assisted reprecipitation (LARP) at room temperature, and the green PeLEDs with good stability were prepared. By comparing the luminous efficiency of CsPbBr3 PeLEDs with the different thicknesses of light-emitting layer, we obtained that the optimal film thickness of the quantum dot light-emitting layer is 43.2 nm, but the external quantum efficiency (EQE) of CsPbBr3 PeLEDs is very low. To improve the electro-optical conversion efficiency of the device, FASn0.3Pb0.7Br3 instead of CsPbBr3 quantum dots are used as the light-emitting layer, and the four different hole transport layers, such as polyvinylcarbazole (PVK), poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt- (4,4'-(N-(4-butylphenyl) (TFB), poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)-benzi (Poly-TPD) and poly[bis(4-phenyl)(2,4,6-triMethylphenyl)aMine] (PTAA), are selected to investigate the effects of different hole transport layers on the photoelectric properties of PeLEDs. The photoluminescence spectra and electrical performance test results show that when the hole transport layer is TFB, FASn0.3Pb0.7Br3 PeLED has a high hole mobility, and the EQE can reach up to 4.2%. The experimental results show that TFB is a suitable material for the hole transport layer of FASn0.3Pb0.7Br3 PeLED. [ABSTRACT FROM AUTHOR]

Copyright of Study on Optical Communications / Guangtongxin Yanjiu is the property of Study on Optical Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal Of Sichuan University (Natural Sciences Division) / Sichuan Daxue Xuebao-Ziran Kexueban is the property of Editorial Department of Journal of Sichuan University Natural Science Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Covalent organic frameworks (COFs), a new type of crystalline porous materials, have attracted considerable attention in many fields such as separation, catalysis, drug release, and optoelectronics. The crystallinity and morphology of COFs determine their application. In this study, the synthetic methods and applications of COFs with different morphologies (spherical, thin film, rod, tubular, fibrous, belt, cage, and roll) are reviewed. Existing problems are also discussed and their potential solutions are proposed. [ABSTRACT FROM AUTHOR]

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the low light extraction efficiency(LEE) of graphene UV light-emitting diode (LED) due to the high absorption of indium tin oxide (ITO) thin layer to UV light, the ITO micro nano structure (rectangle and triangle) was used as the buffer layer of graphene UV LED. The ITO micro nano structure was optimized and graphene UV LED was theoretically analyzed by the finite difference time domain method. The results show that when the thickness, duty cycle and period of rectangular micro nano structure are 160nm and 0. 7,220nm respectively, the LEE of UV LED can reach 10. 668% under single graphene. The use of rectangular micro structure as the insertion layer is 45. 06% higher than that of ITO thin layer as the insertion layer, while when the triangular micro nano structure is in the optimal parameters, the LEE of graphene UV LED is only 6. 64%, significantly lower than that of ITO thin layer. This study can provide a theoretical basis for the subsequent preparation of high-power UV LED. [ABSTRACT FROM AUTHOR]

In the fiber optical sensor demodulation based on asymmetric 3 x 3 coupler, the fiber-optic median phase shift 3 x 3 adder due to the limitation of the manufacturing process and the susceptibility to external environmental interference, and then the three-way signal output has an uneven splitting ratio and an asymmetric phenomenon that the phase difference cannot meet 120°, which causes a problem that could not be accurately corrected. In order to solve these problems, a new 3 x 3 replacer was used, and theoretical analysis and experimental verification were performed. The mean two algorithms were used to pre-process any two signals output, and compressed the original three signals. The power and phase difference between the output signals of the two channels make the new three-channel signals after correction to be approximately symmetrical output, and then perform a symmetric algorithm operation. Simulation and experimental results show that the new scheme can effectively correct the asymmetry of the three output signals of the positive 3 x 3 converter, and classify it. Noise level of the new scheme is about 10 mW and signal-to-noise ratio is about 50dB. Compared with the traditional alternative scheme, the new structure can obtain higher accuracy and signal-to-noise ratio of the signal under test. In addition, according to the simulation and experimental results, the symmetry conditions of the output of the replacer and the anti-noise capability of the new superposition scheme are analyzed. The result has a good guiding role in the field of optical fiber polarizers and accelerates the practical process of optical fiber sensing technology. [ABSTRACT FROM AUTHOR]

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai University / Shanghai Daxue Xuebao is the property of Journal of Shanghai University (Natural Sciences) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

By analyzing massive display inconformity samples, the direct cause and the root cause of display inconformity were found, and on this basis, experiments were designed to improve the display inconformity defect. The analysis indicated that the direct cause of display inconformity was the poi tion shift of pillar spacer caused by gravity; and the root cause was that the size of pillar spacer was too small, so there was no metal line around the pillar spacer which could prevent the pillar spacer from position shift. The result of experiments showed that transport panel by putting it in box, or reducing the duration while panel was putin cassette could obviously improve display inconformity, but were not suitable for production. Furthermore, increasing the size of pillar spacer, so as to decrease the space around pillar spacer could effectively improve the display inconformity defect at the source. By increasing the size of pillar spacer from 15 pm to 23 pm, the defect grade of display inconformity was reduced from Level 4 to Level 2. 5, and the display inconformity defect was greatly improved. [ABSTRACT FROM AUTHOR]

The target in low contrast image cannot be discriminated from cluttered scene by using joint transform correlator as its indistinct edge. Aimed at this problem, an image enhancement based on Curvelet transform was adopted to process the target's joint image. In the wavelet analysis, the Curvelet transform is a better multi-resolution tool to analyze and understand the image feature. Both gray contrast and edge can be enhanced by adjusting the high and low frequency coefficients of Curvelet transform with different methods. As an example, a tank's image with low contrast was processed by using Curvelet transform. The gray contrast of original image was increased from 4.16% to 29.37%. The computer simulation and optical experiment results show that a bright pair of correlation peaks are obtained after enhancing the image, and the recognition for the target in low contrast image is realized successfully. [ABSTRACT FROM AUTHOR]

A high performance controller was designed based on variable structure control (VSC) theory in this paper. The control plant is the typical structure of two axes and four frames, and the controller is sliding mode controller based on Kalman filtering. Comparisons between the controller with filter and the controller without filter were made through tracking different signals when process noise and sensor noise were obvious. The results show that the tracking performance is improved by variable structure control scheme based on Kalman filter, and the accuracy of tracking is enhanced. [ABSTRACT FROM AUTHOR]

To improve the quality of quartz tuning fork and the performance of gyroscope, mass balancing method by which the symmetry of forks is amended is used to improve the impedance characteristics of tuning forks, and the influences of impedance characteristics upon driving of forks and mechanical coupling error are measured. Experimental results showed that by mass balancing method, when the symmetry of driving forks amended, the quality factor of driving forks increased, the driving voltage descended and the mechanical coupling error decreased, the impedance characteristics of quartz tuning fork were improved obviously. [ABSTRACT FROM AUTHOR]