最新刊期
卷 39 ， 期 11 ， 2024
- “最新研究发现，苯基异硫氰酸酯液晶材料在无水环境下稳定性显著提高，为液晶器件应用提供新方案。”摘要：Phenyl isothiocyanate compounds can be used to produce nematic liquid crystal materials with high birefringence. These materials can simultaneously possess high birefringence and low viscosity， and can achieve rapid response in liquid crystal optical devices. However， this type of liquid crystal material is considered to have stability problems， and it is believed that the liquid crystal devices made from it cannot maintain stable operation for a long time. This study found that in accelerated aging experiments， the birefringence of the material decreased by 8.5% after 1 000 h of treatment at 100 ℃. Then， the reasons for the poor stability of isothiocyanate liquid crystal compounds were analyzed by high-performance liquid chromatography and mass spectrometry， confirming that hydroxyl compounds can cause the dissociation of isothiocyanate groups. Finally， the stability of the material was tested in the designed anhydrous environment， and it was shown that the degradation degree of the material was significantly reduced， with a decrease in birefringence of 1.1% under the same conditions. The research in this paper will provide some guidance for the application of such materials.关键词：liquid crystals;isothiocyanate;high birefringence;stability
- 88
- |
- 111
- |
- 0
发布时间：2024-11-28
Material Physics
-
Generation of vector beam array using toric focal conic superstructures of smectic liquid crystals AI导读
“在液晶超结构制备和矢量光阵列产生领域，专家优化了液晶分子排列，成功产生偏振矢量光阵列，为光学陷阱等领域提供新应用。”摘要：This research illustrates the growth and optimization of mesoscopic liquid crystal superstructures， the generation of vector structured beam arrays， and the application of microlens imaging. Utilizing photoalignment technology， we perform hierarchical control of liquid crystal molecular arrangements from the nanoscale layers to microscale domains and， ultimately， to superstructure arrays. Specifically， we design and optimize the quality of smectic liquid crystal toric focal conic superstructures within the cells. This approach allows us to generate and characterize radially polarized vector beam arrays with a polarization order of P=2. Furthermore， we explore the multifunctional application potential of toric focal conic domain arrays as microlens arrays. Our research integrates the topological properties of liquid crystal microstructures with the structured light fields' topological characteristics， leveraging the unique self-assembly capabilities of liquid crystal materials. This integration not only enables the generation， modulation， and detection of specially structured light fields but also suggests potential innovative applications in precision control fields， such as optical trapping， microfluidic control， and high-resolution imaging.关键词：liquid crystal;smectic phase;photoalignment;toric focal conic domain;vector beams;microlens array- 115
- |
- 106
- |
- 0
发布时间：2024-11-28 - “科技媒体新闻记者报道：最新研究揭示了一种新型空间光调制器G-LCoS的反射相位特性，为AR/VR显示系统和全息视频显示优化提供了新思路。”摘要：Spatial light modulator （SLM） is a key device to realize light field modulation. In this paper， the reflection phase characteristics of a SLM （G-LCoS） device model consisting of a subwavelength gold grating embedded in a liquid crystal on silicon （LCoS） are investigated， which is composed of an ITO transparent conductive layer and liquid crystals to form the asymmetric boundary of a subwavelength gold grating in G-LCoS. Firstly， the expression for the reflection phase of the subwavelength gold grating is given by applying the scattering matrix principle. Secondly， the formula for the effective refractive index of the liquid crystal on the lower surface is given. On this basis， TechWiz 3D software is used to simulate the change of the pointing vector of the liquid crystal on the lower surface of the gold grating when applying an additional voltage， and the change value of the effective refractive index of the liquid crystal on the lower surface of the gold grating is given. The obtained effective refractive index data are imported into FDTD Solutions software， and relevant simulation experiments and results are analyzed for the device structure. The ITO dispersion of the upper surface， the change of the height of the gold grating and the value of the effective refractive index of the liquid crystal at different voltages are taken into account to realize the near
- 84
- |
- 125
- |
- 0
发布时间：2024-11-28 - “在环保显示技术领域，研究人员探索了提升光重构液晶电子纸响应速度的多种方法，为实现更快速、更高效的显示方案提供解决方案。”摘要：Compared to traditional liquid crystal displays， liquid crystal electronic paper devices based on Optically Rewritable （ORW） technology exhibit significant advantages such as being environmentally friendly， low power consumption， high portability and low cost， which has attracting considerable attention. The working principle of liquid crystal display electronic paper based on ORW technology involves using irradiation light to precisely control the alignment direction of liquid crystal molecules， enabling rapid optical erasure and rewriting of the display images. Although ORW liquid crystal electronic paper display technology has many advantages， its application is still limited by the technical bottleneck of long optical response times. To address this issue， researchers have explored various methods to enhance response speed. This article will focus on research methods such as optimizing the manufacturing process， applying fast-response liquid crystal materials， optimizing operating temperatures， doping specific materials in the alignment layer or liquid crystal layer， and improving the respond speed of the device by changing the intensity of the driving light. A brief introduction is also given to the applications of ORW technology in both display and non-display fields. With continuous technological advancements and innovations， ORW technology is expected to offer faster and more efficient display solutions in the future to meet the growing market demand.关键词：liquid crystal display;optical rewritable;electronic paper;response speed
- 82
- |
- 101
- |
- 0
发布时间：2024-11-28 - “在液晶显示屏质量检测领域，机器视觉技术凭借高效率、低成本优势成为主要手段。本文重点探讨了人工智能技术在TFT-LCD表面Mura缺陷检测的应用，并展望了技术发展趋势。”摘要：Surface defect inspection is crucial for ensuring the quality stability of liquid crystal display （LCD） screens， particularly for TFT-LCDs.Known for its high efficiency and low cost， machine vision technology has become the primary means for inspecting TFT-LCD quality. This paper reviews the development of LCD and lists the common types of Mura defects. The traditional image processing methods and deep learning for detecting Mura defects are introduced， and recent advancements in image preprocessing techniques such as image filtering and brightness correction are summarized. The application of artificial intelligence techniques， such as supervised learning， unsupervised learning and transfer learning is introduced， in the detection of Mura defects on TFT-LCD surfaces. Finally， the research directions for machine vision-based Mura defect inspection technology on TFT-LCD are anticipated.关键词：TFT-LCD;Mura defects;machine vision;image processing;deep learning
- 149
- |
- 173
- |
- 0
发布时间：2024-11-28 - “在生物学领域，专家利用贝塞尔光束特性，成功研发新型双光子光片显微镜，实现活体生物三维高分辨率成像。”摘要：Two-photon light-sheet microscopy offers high resolution and low photobleaching， making it widely used in biological research. However， a trade-off between light sheet thickness and length limits its axial resolution and field of view， restricting its applications. To address this issue， this paper employs a liquid crystal spatial light modulator （SLM） to modulate conventional Gaussian illumination beam into Bessel beam. The “non-diffracting” property of the Bessel beam enables the generation of a large and thin light sheet， achieving a length-to-thickness ratio of 163. Based on this， a Bessel two-photon light-sheet microscope is constructed， achieving three-dimensional high-resolution imaging with a lateral resolution of 440 nm and an axial resolution of 1.9 μm within a 310 μm field of view. Successful in vivo imaging of zebrafish embryos is demonstrated， including the measurement of blood cell flow velocity and the segmentation and counting of spinal cord cells， validating the application potential of the Bessel two-photon light-sheet microscope in live biological imaging.关键词：Liquid crystal spatial light modulator;two-photon light sheet microscopy;bessel beam;in vivo imaging
- 41
- |
- 82
- |
- 0
发布时间：2024-11-28
Liquid Crystal Optics
- “在三维重建领域，研究者提出了基于神经辐射场的框架，有效解决了少视图重建中结构模糊问题，为三维场景重建提供了新方案。”摘要：Few view 3D reconstruction requires only fewer views to recover the 3D geometry of an object or scene. However， the lack of sufficient information to accurately restore the 3D scene due to the under-coverage on different viewpoints in the fewer views can lead to inaccurate or blurred reconstruction results. In this paper， a neural radiation field-based framework is proposed to solve the problem of structural blurring by utilizing accurate cost costumers to correlate foreground and back view depth information. First， the local features of the foreground and the backscene are extracted using a pyramid network to enhance the capture of the scene details， and the self-attention mechanism is introduced to ensure that the key regions are attended to during the feature extraction process. Then， the smooth transfer of feature scales is realized by the adaptive sensory field module as a way to construct an accurate feature cost volume. Finally， random structural similarity loss is introduced to replace pixel-by-pixel supervision by utilizing local area pixels as a whole supervision to capture the structural information in the scene more comprehensively. The experimental results show that in the DTU dataset， PSNR and LPIPS can achieve optimal results and SSIM can achieve suboptimal results compared with the comparison methods， and PSNR， LPIPS and SSIM are improved by 0.478， 0.001 and 0.01， respectively. Compared with the baseline model， experiments on the DTU dataset， the LLFF dataset and the NeRF dataset show that the method proposed in this paper can effectively solve the structural ambiguity problem caused by insufficient information in view less 3D reconstruction.关键词：3D reconstruction;neural radiance field;cost volume;structural ambiguity
- 69
- |
- 126
- |
- 0
发布时间：2024-11-28 - “在图像语义分割领域，研究者提出了基于双交叉注意力网络的小样本分割方法，有效提升了新类别分割性能。”摘要：Few-shot semantic segmentation can segment novel classes with only few examples. To address the problem of insufficient semantic information mining in existing methods， a method based on Dual Cross-Attention Network for few-shot image semantic segmentation is proposed. The method adopts Transformer structure and uses dual cross-attention modules to explore the remote dependencies between multi-scale query and support features from both channel and spatial dimensions. Firstly， a channel cross-attention module is proposed in combination with the position cross-attention module to form a dual cross-attention module. Wherein， the channel cross-attention module is applied to learn the channel semantic interrelationships between the query and support features. The position cross-attention module is used to capture the remote contextual correlations between the query and support features. Then， multi-scale interaction features containing rich semantic information can be provided to the query image by multiple dual cross-attention modules. Finally， to obtain accurate segmentation results， auxiliary supervision loss is introduced， and these multi-scale interaction features are connected to the decoder via upsampled and residual connection. The proposed method achieves 69.9% （1-shot） and 72.4% （5-shot） mIoU on the dataset PASCAL-5i， and 48.9% （1-shot） and 54.6% （5-shot） mIoU on the dataset COCO-20i， which attains the state-of-the-art segmentation performance in comparison with mainstream methods.关键词：Few-shot semantic segmentation;transformer architecture;channel cross-attention;dual cross-attention;auxiliary losses
- 75
- |
- 136
- |
- 0
发布时间：2024-11-28 - “在手部图像分割领域，研究者提出了基于注意力机制的多尺度分割方法，有效提升了分割精度和鲁棒性。”摘要：Aiming at the problem of inaccurate segmentation of hand edge detail information and missed detection of small-area hand， a multi-scale hand segmentation method based on attention mechanism is proposed. Firstly， the Transformer module is redesigned and optimized， and the window self-attention structure and D-FFN mechanism are proposed. The window self-attention mechanism integrates global and local dependent information， and D-FFN suppresses the interference of background information. Then， a multi-scale feature extraction module combining strip pooling and cascade network is proposed to increase the receptive field and improve the accuracy and robustness of the hand segmentation model. Finally， an up-sampling decoder module based on Triplet Attention mechanism is proposed. By adjusting the attention weight of channel dimension and spatial dimension， the redundant features of target features and background are distinguished. The proposed algorithm is tested on public datasets GTEA （Georgia Tech Egocentric Activity） and EYTH （EgoYouTubeHands）. Experimental results show that average MIoU values of the algorithm on the two datasets reach 95.8% and 90.2%， respectively， which is 2.5% and 2.1% higher than the TransUnet algorithm. It meets the requirements of stable and reliable， high precision and strong anti-interference ability of hand image segmentation.关键词：hand segmentation;deep learning;TransUnet;feed-forward networks;atrous spatial pyramid pooling;triplet attention
- 61
- |
- 93
- |
- 0
发布时间：2024-11-28 - “在图像质量评价领域，研究者提出了一种结合元学习和失真感知的图像质量评价方法，有效提升了模型在不同失真类型间的泛化性能，并在评价精度上具有竞争力。”摘要：The cost of obtaining subjective quality scores for images is often high， image quality assessment （IQA） models commonly face the challenge of insufficient training samples. Additionally， the type of distortion has a significant impact on the perceived visual quality of images. In light of these considerations， this paper proposes an image quality assessment method that combines meta-learning and distortion perception. Firstly， meta-learning is employed to simulate the human learning process， enabling the rapid acquisition of prior knowledge about known distortion types. This knowledge guides the subsequent ResNet-50 network in effectively integrating multi-scale features. The introduction of a distortion perception module captures comprehensive distortion information， establishing a unified quality assessment framework. Experimental results on synthetic and real distortion datasets such as LIVE and KonIQ-10k indicate that the proposed model under small sample conditions can enhance the generalization performance across different distortion types. In comparison with the existing advanced methods， the model in this paper achieves 1.02% and 1.85% improvement in PLCC and SROCC evaluation indexes compared with the second-best method. In comparison with mainstream IQA models， the evaluation accuracy shows competitive performance.关键词：No-reference image quality assessment;meta learning;distortion perception;generalization performance
- 51
- |
- 155
- |
- 0
发布时间：2024-11-28 - “在图像去雾领域，Firs-Net基于分数匹配扩散模型IR-SDE，利用傅里叶特征融合模块，有效提升了真实有雾图像的去雾效果。”摘要：The current research on image dehazing algorithms mainly focuses on building intricately structured neural networks. There is a lack of research on using diffusion models and generative methods for image dehazing， and there is also relatively little research on combining diffusion models with frequency domain analysis. This results in many algorithms having poor dehazing effects when processing real hazy images. In response to the above issues， a Firs-Net image dehazing method is proposed based on the score matching diffusion model IR-SDE. This method utilizes the powerful image generation ability of diffusion models to gradually restore clear and hazy-free images from hazy images in an iterative manner. Firs-Net introduces a Fourier feature fusion module， which can help the diffusion models better analyze and fuse features from a frequency domain perspective without increasing the number of parameters and fine-tuning the neural network. The experimental results show that Firs-Net performs excellently in both subjective visual and objective indicators on real hazy datasets， with a PSNR of 21.91 in the NH-HAZE dataset of real non-uniform haze， and a PSNR of 17.40 in the real dense haze dataset Dense-HAZE， which is 13.94% and 5.52% ahead of the suboptimal method， respectively.关键词：computer vision;image dehaze;diffusion models;fourier filter
- 92
- |
- 98
- |
- 0
发布时间：2024-11-27 -
Lightweight method of feature point extraction and matching incorporating a progressive strategy AI导读
“在特征匹配领域，研究者提出了一种融合渐进式策略的轻量化特征点提取与匹配方法，有效提升了特征点提取准确率和计算效率。”摘要：To address the issues of the feature-matching method based on the SuperPoint network， such as low accuracy in feature-point extraction and high computational cost under challenges of lighting， pose and angles， a lightweight feature point extraction and matching method under a progressive strategy is put forward. Firstly， to reduce the model’s computational cost， the SuperPoint network is modified using depthwise separable convolution. Secondly， an attention module is built in the feature extraction part to strengthen the network’s spatial feature extraction capability. Also， a progressive multi-scale feature fusion module is designed to capture object details and boost feature representation capabilities. Finally， the obtained feature points are matched using the SuperGlue algorithm. Experimental analysis on the Hpatches dataset shows that the proposed algorithm achieves an average matching accuracy （mAP） of 86% and feature point repeatability （Rep） of 70% in illumination change scenarios， and mAP of 78% and Rep of 68% in viewpoint change scenarios. The proposed algorithm not only shows certain advantages in feature matching， but also achieves good results when applied to video stitching.关键词：feature point extraction;feature point matching;lightweight;attention mechanism;progressive multi-scale feature fusion- 34
- |
- 49
- |
- 0
发布时间：2024-11-28 - “最新研究提出基于改进ShuffleNetV2网络和知识蒸馏的遥感图像分类方法，有效提升分类精度，缩减参数量。”摘要：In response to the challenges posed by traditional remote sensing scene classification models， which are characterized by a large number of parameters requiring substantial computational resources， and issues related to uneven feature recognition leading to low classification accuracy， this study proposes a remote sensing image classification method based on an improved ShuffleNetV2 network and knowledge distillation. To address the difficulty in uniformly extracting subtle features in remote sensing scenes at long distances and high altitudes， we introduce the CBAM channel space attention mechanism. Furthermore， we modify the basic stacking unit of ShuffleNetV2 to be lightweight. Finally， employing transfer learning and knowledge distillation techniques， we load a pre-trained model with ResNet101 as the teacher network and the enhanced ShuffleNetV2 as the student network to enhance remote sensing image classification accuracy. Experimental results demonstrate that the improved ShuffleNetV2 reduces parameter count by 28% while increasing accuracy from 91.8% to 94.8%. Compared with lightweight models such as MobileNetV3 and MobileViT， our approach achieves improvements of 4.2% and 4.5%， respectively. Importantly， our enhanced model maintains high classification accuracy while occupying less storage space.关键词：deep learning;image classification;attention mechanism;lightweight neural network;knowledge distillation
- 62
- |
- 102
- |
- 0
发布时间：2024-11-28 - “在目标跟踪领域，研究者基于Swin-Transformer网络提出了改进算法，有效提升了跟踪性能。”摘要：An improved target tracking algorithm is proposed based on the Swin-Transformer network to address the problem of insufficient feature extraction capability and poor tracking effect often encountered when using convolutional neural networks in deep learning-based target tracking methods. Firstly， the window attention mechanism of the Swin-Transformer is enhanced across multiple scales， and a multi-scale window module termed MW-MSA is devised to extract more comprehensive local detail information. This augmentation， in conjunction with global contextual insights， engenders multi-scale discriminative features. Then， these features are integrated with the encoding-decoding structure of the Transformer， serving as the feature fusion network. An optimized multi-layer perceptron is employed as the update score judgment network to establish the state awareness module. Finally， a multi-tracker fusion method is proposed to address challenges like target occlusion and disappearance by integrating an improved tracking algorithm with the SuperDiMP tracking algorithm. Results from testing on L-LaSOT and GOT-10K datasets show significant improvements over the STARK tracking algorithm： a 2.7% increase in average overlap rate （AO） and a 3.3% increase in success rate （SR） on GOT-10K， and a 0.8% increase in success rate （AUC） on L-LaSOT. Moreover， under the target disappearance challenge， the success rate is improved by 1%.关键词：target tracking;multi-scale windows;Swin-Transformer;template update;multi-tracker fusion
- 74
- |
- 74
- |
- 0
发布时间：2024-11-28
Image Processing
- Address：No.3888 Dong Nanhu Road, Changchun, Jilin, China 130033 Postal code：130033
- Tel：0431-86176059 Email：yjxs@ciomp.ac.cn
- Technical support is provided by Beijing Founder electronics co., LTD 吉ICP备11002662号-17
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0