3D Display Research Articles

Temporal multiplexing complex amplitude holography for 3D display with natural depth perception

In this Letter, we develop a temporal multiplexing complex amplitude holography for a three-dimensional (3D) display with natural depth perception. A series of band-limited random phases is optimized through the designed pseudo incoherent wave propagation model, which can be used as the initialization condition for arbitrary target images. The temporal multiplexing holograms (TMHs) are calculated according to the optical field distribution in the image plane and encoded through the complex amplitude converting method. Based on temporal multiplexing, our method overcomes the drawbacks brought by random phase and constant phase on 3D display performance and enables 3D reconstruction with high image quality as well as natural depth cues. It is expected that our method offers an efficient route toward the future high-performance holographic 3D display.

Speckle‐Free 3D Holography in the Wigner Domain

AbstractComputer‐generated hologram (CGH) provides an approach to modulate the 3D coherent wavefront and has been widely used in many optical applications. Over the past few decades, extensive efforts have been made to design optimization models for high‐quality reconstruction. However, the reconstruction quality is still limited due to the mismatch of the bandwidth between the reconstructed field of interest and the reconstructed complex amplitude field in 3D space. Here, an ideal numerical light field mapping physical model from the hologram plane to the 3D image plane for speckle‐free 3D holography in the Wigner domain is established. With the aid of the Wigner distribution function (WDF), which allows the analysis of a light field from not only the space domain but also the spatial frequency domain, the bandwidth properties of the reconstructed field in 3D space are analyzed, which provides a guideline for the sampling of the reconstructed field to efficiently describe the speckles and artifacts. Accordingly, a comprehensive CGH optimization method in the Wigner domain is proposed to constrain the reconstructed intensity fluctuations without errors and omissions for high‐quality reconstruction. As such, this method enables speckle‐free and artifact‐free reconstruction with a twice improvement in peak signal‐to‐noise ratio (PSNR) and a five times improvement in structural similarity index measure (SSIM) compared to conventional phase‐only holograms. The optical experimental results show that this method paves the road for the future implementation of speckle‐free color 3D holography harnessing the advanced integrated photonic devices, and also offers an efficient and practical route for various optical applications, such as 3D display, optical encryption, beam shaping, optical computing and so on.

A customization design platform for school uniforms using the Kano model

PurposeThis study aims to explore a methodology based on the Kano model. And use this method to determine user requirement attributes in the field of school uniform customization. To construct a set of processes that can be used as a reference for constructing a clothing customization platform.Design/methodology/approachAn optimized quantitative Kano model was applied. Initially, a survey was conducted to assess the current market for customized school uniforms in China. Subsequently, a Kano attribute questionnaire was developed, and experts from both supply and procurement sectors were invited to evaluate it. This was followed by categorizing user demands based on the Kano model’s evaluation criteria and conducting a validity analysis using Cronbach’s alpha coefficient. The priority ranking of user demands was determined through a sensitivity analysis of better-worse coefficients. Ultimately, a platform was established, and a fuzzy comprehensive evaluation was conducted.FindingsRegarding user demands, procurement-side demand elements prioritize modular design, fabric libraries and online reviews. In contrast, supply-side demand elements focus on style product libraries, layout adaptation to user habits and the preview effects of 3D models. Elements such as qualification verification, personal information uploading, design draft archiving and main tag categorization have a lesser impact on user satisfaction.Originality/valueThe results of the study provide a complete methodological reference for the construction of a garment customization platform. By applying the Kano model, this study categorizes and filters the demands of users for school uniform customization design platforms in China and establishes a 3D virtual display platform aimed at improving user satisfaction.

Three-dimensional bioprinting utilizing sacrificial material support and longitudinal printability evaluation through volumetric imaging.

In three-dimensional (3D) bioprinting, the internal channel network is vital for nutrient and oxygen transport, crucial for cell survival and tissue construction. However, bioinks' poor mechanical properties hinder precise control over these networks. Advancements in 3D printing strategies, structure characterization, and deformation monitoring can improve hydrogel scaffolds with interconnected channels. Using label-free, non-invasive, in-situ optical coherence tomography (OCT) imaging, we monitored the dynamic deformation of 3D bioprinted hydrogel scaffolds. We validated sacrificial materials' role in enhancing internal channels and introduced deformation characteristics, lateral pore ratio and pore-specific surface area as new parameters. Results from cell-laden hydrogels show that 3D bioprinting with sacrificial materials achieves high fidelity, minimizing collapse, inter-filament fusion, and enhancing lateral porosity. Furthermore, these promote cell proliferation and cell viability.

PreVISE: an efficient virtual reality system for SEEG surgical planning.

Epilepsy is a neurological disorder characterized by recurring seizures that can cause a wide range of symptoms. Stereo-electroencephalography (SEEG) is a diagnostic procedure where multiple electrodes are stereotactically implanted within predefined brain regions to identify the seizure onset zone, which needs to be surgically removed or disconnected to achieve remission of focal epilepsy. This procedure is complex and challenging due to two main reasons. First, as electrode placement requires good accuracy in desired brain regions, excellent knowledge and understanding of the 3D brain anatomy is required. Second, as typically multiple SEEG electrodes need to be implanted, the positioning of intracerebral electrodes must avoid critical structures (e.g., blood vessels) to ensure patient safety. Traditional SEEG surgical planning relies on 2D display of multi-contrast volumetric medical imaging data, and places a high cognitive demand for surgeons' spatial understanding, resulting in potentially sub-optimal surgical plans and extensive planning time (~ 15 min per electrode). In contrast, virtual reality (VR) presents an intuitive and immersive approach that can offer more intuitive visualization of 3D data as well as potentially enhanced efficiency for neurosurgical planning. Unfortunately, existing VR systems for SEEG surgery only focus on the visualization of post-surgical scans to confirm electrode placement. To address the need, we introduce the first VR system for SEEG planning that integrates user-friendly and efficient visualization and interaction strategies while providing real-time feedback metrics, including distances to nearest blood vessels, angles of insertion, and the overall surgical quality scores. The system reduces the surgical planning time by 91%.

Three-Dimensional Time-Series Monitoring of Maize Canopy Structure Using Rail-Driven Plant Phenotyping Platform in Field

The spatial and temporal dynamics of crop canopy structure are influenced by cultivar, environment, and crop management practices. However, continuous and automatic monitoring of crop canopy structure is still challenging. A three-dimensional (3D) time-series phenotyping study of maize canopy was conducted using a rail-driven high-throughput plant phenotyping platform (HTPPP) in field conditions. An adaptive sliding window segmentation algorithm was proposed to obtain plots and rows from canopy point clouds. Maximum height (Hmax), mean height (Hmean), and canopy cover (CC) of each plot were extracted, and quantification of plot canopy height uniformity (CHU) and marginal effect (MEH) was achieved. The results showed that the average mIoU, mP, mR, and mF1 of canopy–plot segmentation were 0.8118, 0.9587, 0.9969, and 0.9771, respectively, and the average mIoU, mP, mR, and mF1 of plot–row segmentation were 0.7566, 0.8764, 0.9292, and 0.8974, respectively. The average RMSE of plant height across the 10 growth stages was 0.08 m. The extracted time-series phenotypes show that CHU tended to vary from uniformity to nonuniformity and continued to fluctuate during the whole growth stages, and the MEH of the canopy tended to increase negatively over time. This study provides automated and practical means for 3D time-series phenotype monitoring of plant canopies with the HTPPP.

Circularly Polarized Luminescence in Cellulose-Based Assemblies: Synthesis, Regulation, and Application.

Currently, circularly polarized luminescence (CPL) has drawn wide interest in 3D display, information storage, and optical sensing. However, traditional synthetic paths are often accompanied by low chiral optical intensity and complex processes. Cellulose nanocrystals (CNCs), with the properties of liquid crystals, can spontaneously arrange into the left-handed layered nanofilm, which enables them candidates in the construction of CPL materials. Following this approach, this work reviews the synthesis of cellulose-based chiral luminescent materials. The co-assembly technique, in situ intercalation strategy, and defect destruction design are efficient in encapsulating the luminophores into the CNC organization. Next, various strategies on the CPL regulation, including the matching of the photonic bandgap, optical pathway design, and tailored helical structure, are summarized. These offer new sights in the CPL control, mainly focusing on the amplification and inversion of optical signals. Multimodal and convertible chiroptical signals enable the photonic films with practical values in anti-counterfeit, sensing, and handedness induction. Overall, this timely overview summarizes the synthesis, regulation, and application of cellulose-based CPL materials, and aims to inspire the development of the chiral optical materials.

High-Resolution Electrohydrodynamic Printing with Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) Conductive Polymers

Conductive polymer materials, particularly PEDOT:PSS conductive polymers, have gained widespread attention due to their excellent conductivity, processability, and biocompatibility, making them highly applicable in fields such as bioelectrodes, flexible sensors, and soft robotics. With the rapid development of flexible electronics, the demand for micron-scale precision in the processing of conductive polymers grows. However, advanced fabrication techniques, such as 3D printing and screen printing, which are currently popular in research, face challenges in achieving a micron-level resolution, limiting the further application of conductive polymers. In this study, we demonstrate three types of PEDOT:PSS inks and systematically explore their suitability for electrohydrodynamic (EHD) jet printing. We investigate the impact of critical parameters, including voltage, printing speed, and printing height, on the accuracy of printed patterns. Among the formulations, the optimized PEDOT:PSS to ethylene glycol ratio of 1:1 achieves line widths of 20 µm. Based on this ink, we successfully print flexible conductive polymer patterns with line widths ranging from 20 µm to 90 µm and fabricate PEDOT:PSS conductive films with dimensions of 1.5 cm × 0.5 cm. This high-precision PEDOT:PSS ink demonstrates a strong potential for applications in high-density electrode arrays, electrochemical transistors, and brain–machine interfaces, paving the way for advanced flexible electronics.

Light-field generation for 3D light-field display with IARF and adaptive ray sampling.

High-quality light-field generation of real scenes based on view synthesis remains a significant challenge in three-dimensional (3D) light-field displays. Recent advances in neural radiance fields have greatly enhanced light-field generation. However, challenges persist in synthesizing high-quality cylindrical viewpoints within a short time. To handle these issues, the instant adaptive radiance field (IARF) method is proposed to enhance the synthesized light-field quality from a set of captured images. In the ray marching process, the adaptive ray sampling technique is presented for resampling within both discrete occupied grids and continuous unoccupied spaces, which ensures that more representative points are acquired, thereby improving image quality. Furthermore, the volumetric sampling consistency (VSC) loss is used for adaptive ray sampling, which maintains the consistency, contributing to shorter training times with high quality. The iterative network structure of IARF is designed to achieve the resampling of points along emitted rays, which ensures the convergence of the density distributions and enhances synthesis accuracy. The distortion loss is introduced to optimize the unbounded scene geometry, and more realistic rendering is achieved. Finally, the expected viewpoint rendering with a backward ray tracing technique is presented to directly render synthetic images based on off-axis light-field image coding. Experimental results validate the effectiveness of our method. The IARF can achieve more detailed viewpoint generation for 360-degree scenes in a shorter training time. The ablation study demonstrates the validity of the proposed VSC loss and utilized distortion loss. Compared to other established methods, an average improvement of 2.14 dB in PSNR is achieved with approximately 9 minutes of training. The IARF can generate synthetic images at arbitrary positions and viewing angles within the scene, rather than being limited to a narrow field of view. Notably, a smooth motion parallax is obtained based on the 3D light-field display with 7680×4320 resolution over a large viewing angle. We believe that the IARF method can facilitate light-field generation by synthesizing real-world scenes, which represent a promising application for 3D light-field display.

Ultrathin, Wavelength‐Multiplexed and Integrated Holograms and Optical Neural Networks Based on 2D Perovskite Nanofilms

AbstractHolography, as a technique for coherent wavefront reconstruction, is extensively used in numerous optical applications such as optical imaging, 3D display, photolithography, and optical artificial intelligence. In order to achieve highly compact and functional integration with optoelectronic devices, the hologram needs to possess ultrathin thickness as well as multicolor functionality. However, its thickness is typically limited to optical wavelength ranges due to the requirement for pronounced amplitude or phase modulation, and it generally operates at a single wavelength band without wavelength‐multiplexed channels. Here, the hologram is decreased thickness to sub‐ten nanometers by exploiting the large refractive index and strong exciton absorption of 2D perovskites. Ultrathin perovskite holograms and holographic neural networks with high stability are successfully developed by using femtosecond laser direct writing, and their operation wavelength can be rationally tuned from 400–515 nm through halide anion engineering. Consequently, the wavelength can be multiplexed with low cross‐talks by stacked perovskite nanolayers for applications of holographic display and neural networks without the usages of complex optical structures or filters. This work provides a feasible and promising technical route for integrating ultrathin, high pixel density, and multiplexed holographic structures with flat optoelectronic devices for next‐generation integrated optical systems.

Diffraction model-driven neural network with semi-supervised training strategy for real-world 3D holographic photography

Compared to traditional 2D displays, 3D display technology provides richer information to the viewer. Learning-based computer-generated holography (CGH) has shown great potential in realizing real-time holographic 3D displays. However, most of the current learning-based CGH algorithms cannot quickly complete the training stage and produce high-quality holograms due to insufficient constraints in the training stage of the neural network. In this paper, we propose a diffractive model-driven neural network trained using a semi-supervised training (SST-holo) strategy and incorporate a state-of-the-art monocular depth estimation algorithm to achieve the fast generation of holograms of real-world 3D scenes. Compared to the supervised training strategy, our proposed semi-supervised training strategy does not require high-quality labeled datasets, but can significantly improve the imaging quality and generalization of the algorithm. Incorporating the Res-MSR block in SST-holo to adaptively learn image features of different scales enhances the learning capability of the network. In addition, we adopt a random splicing processing strategy to preprocess the dataset to ensure that the original features in the dataset are not corrupted. SST-holo can generate high-quality 3D phase-only holograms with 2 K resolution in 0.015 seconds. Both monochrome and color optical experiments show that the proposed algorithm has good 3D effect and generalization ability and can effectively improve the quality of reconstructed images.

Virtual Reality in Clinical Teaching and Diagnostics for Liver Surgery: Prospective Cohort Study

Abstract Background Learning and applying anatomy are essential but are studied and done through 2D tools and imaging techniques. This study aims to verify the usefulness of an additional 3D technique and ensure an improvement in the visualization of anatomical structures and pathological findings. Objective The study aims to examine the usefulness of virtual reality (VR) technology as an additional tool in medical diagnostics. Groups of students, residents, and specialists in surgery, radiology, and internal medicine evaluated magnetic resonance imaging (MRI) by answering a multiple-choice questionnaire. Subsequently, a virtual 3D display was used for processing. The questionnaire focused on topographical conditions and the transfer of academic knowledge into clinical application. The main objective was to determine anatomical understanding in a comparison between sectional image (2D) presentation and additional VR (3D) presentation, measured through correctly answered questions and processing time. The system usability scale (SUS) was integrated as another criterion for VR usability. Methods The cross-over study assessed 63 participants regarding their knowledge of liver anatomy and pathologies based on an interindividual comparison. Group formation according to the respective level of medical training was as follows: students (n=35), residents (n=15), and specialists (n=13). Participants answered 25 multiple-choice questions first using sectional imaging (MRI) in a 2D environment (computer screen) and afterward with the respective segmented 3D model visualized in a VR simulation. The main criteria for the analyses were the number of correctly answered questions and processing time. A customized SUS was used to analyze VR usability. Missing data analysis showed that there were no accounted missing data. Results The rate of correct answers improved significantly with the additional use of VR (F1,59=314.376; P<.001). Using MRI, a significant difference was observed between students and residents (P=.04) and between students and specialists (P<.001). In the VR condition, no significant differences between groups were found. In the MRI condition, significant differences in processing time were observed between students and specialists (P=.02) and between residents and specialists (P=.04). No differences existed between students and residents. With VR, processing time decreased significantly in all groups (F1,59=280.700; P<.001). Significant differences between students and specialists (P=.02) and between students and residents (P=.004) remained. No notable differences between residents and specialists (P=.72) were found. The SUS showed a subjectively simplified answerability of the questions with additional use of VR. The usefulness and benefits for an additional use of VR were stated. Conclusions The additional use of VR suggests statistically significant improvements across all groups. VR seems to enable students and residents to participate in diagnostics and create treatment plans at an early stage. Transferred to clinical practice, this may lead to improvement in diagnostics and interventions. The lack of randomization and a potential learning effect are the main limitations to be addressed in future studies.

Outdoor mesoscale fabricated ecosystems: Rationale, design, and application to evapotranspiration

The disparity in scale, complexity, and control level between laboratory experiments and field observational studies has shaped both the methodologies employed and the nature of the research questions pursued in ecology and hydrology. While lysimeters and fabricated ecosystems suitably fit in this gap, their use as mesoscale experimental facilities has not been fully explored because of the limited manipulating capabilities and integration with imaging and monitoring methods, particularly for soil functioning. The proposed fabricated ecosystem (4.7 L × 1.2 W × 1.2 H m) focuses on the spatiotemporal integration of point sensors and imaging methods along the soil-plant-atmosphere continuum. Because energy and water fluxes are key environmental drivers, the designed setup was first applied to a multi-approach evapotranspiration investigation. Below the ground, electrical resistivity tomography (ERT) was combined with soil water sensors and a distributed temperature profiling system. Together, they provided the 3D monitoring of water and temperature changes, and thus an estimation of the evapotranspiration, as well as the interpretation of its below-ground controlling processes. Above-ground sensors supported a classical energy balance investigation that was compared with the lysimeter load changes and the ERT-based ET estimation. Our results provide first experimental evidence of water and temperature spatiotemporal variability at the lysimeter scale, and thus explain the discrepancies among the three estimated evapotranspiration time series and their seasonality. Beyond evapotranspiration, the multi-approach investigation of water and energy fluxes emphasizes how mesoscale setups can further support the development and upscaling of methods and models, as well as their integration and application under expected climate disturbances.

Preliminary Development of Vircadia Virtual Reality Platform for Monitoring Water Quality Powered by Solar Panels

Climate change is a global issue that significantly challenges water resources, especially in regions with limited public awareness about water conservation. It manifests through rising global temperatures, shifting weather patterns, more frequent and intense natural disasters, and instability in water availability. These problems are worsened by low public awareness and the reliance on steam power plants for water pumps. Addressing these challenges requires educational media that raises awareness about the causes and impacts of climate change. This study introduces the early development of a Virtual Reality (VR) platform utilizing Vircadia, focused on creating a 3D world and monitoring water quality with the support of solar power. Vircadia, an open-source platform, offers developers the flexibility to build and host virtual worlds on their servers, providing greater control over the environment, scalability, and customization. With Vircadia, we can rapidly implement a VR platform that integrates custom assets from Blender and personalized avatars from Ready Player Me. Vircadia can seamlessly connect to IoT platforms via weblink, allowing for real-time monitoring of water quality parameters and enabling users to interact directly with and oversee IoT devices within the VR environment. This paper discusses why we chose Ready Player Me and Blender as platforms for building 3D avatars and assets, and Vircadia as the VR Platform. Additionally, it addresses challenges encountered when using Vircadia, such as asset optimization and IoT device integration. Future research will focus on optimizing asset quality, enhancing IoT integration, and implementing carbon emissions monitoring within the VR platform.

High temperature in-situ 3D monitor of microstructure evolution and heat transfer performance of metal foam

Metal foams with excellent mechanical properties and low effective thermal conductivity (ETC) are widely used in high-temperature components. The 3D microstructure evolution under high-temperature loading is complex. The deformation mode and ETC at high temperature of metal foams are determined by the microstructure at different stress and the parent material properties. In this paper, high-temperature in-situ micro X-ray computed tomography (μ-CT) compressive test was performed to monitor the 3D microstructure evolution and failure mechanism of closed-cell Al foams at 300 ℃. High-fidelity material twin models were then generated from the in-situ μ-CT scans under various high-temperature loadings to calculate the corresponding ETC of the foams. The effects of the applied strain and corresponding 3D microstructure on the ETC were discussed based on experimental and simulation results. The results reveal that the 3D porosity and ETC evolution of foam compressed at 300 °C are bilinear. A compressive strain of 30 % was identified as a critical strain, beyond which both porosity and ETC change dramatically with increasing strain. Finally, a theoretical model based on the Kelvin tetrakaidecahedron was developed to reveal the effect of microstructure evolution caused by compressive strain on the ETC of foams.

3D scanner measuring preterm infants’ head circumference and cranial volume: validation in a simulated care setting

IntroductionWeekly head circumference (HC) measurements using a measuring tape is the current standard for longitudinal brain growth monitoring of preterm infants. The MONITOR3D (M3D) 3D scanner has been developed to measure both HC and cranial volume (CrV) of preterm infants within incubators. The M3D’s usability, accuracy and precision were validated in a simulated setting in a neonatal intensive care unit (NICU).Materials and methodsDuring a simulated routine care moment, NICU nurses conducted M3D scans of a preterm doll simulating an extreme low birthweight preterm (ELBW; BW < 1,000 g) infant, followed by manual HC measurements using a measuring tape. Usability was quantified by percentage of successful HC and CrV measurements from scans. HC and CrV were calculated by marking anatomical landmarks on the 3D image. Measurements were compared to the real, ground truth (GT) values of the doll’s head, defined by an accurate medical scanner. Measurement accuracy was assessed using mean or median absolute measurement error (ME), and precision by the spread of ME, represented by the 95% interval of the ME range. ME intervals were compared with preterm weekly growth increases to assess clinical usability.ResultsRegarding usability, 56 M3D scan sessions resulted in 25 successful (44.6%) HC and CrV measurements, with incomplete 3D data being the primary cause of unsuccessful scans. Accuracy of the measuring tape for HC was 0.2 cm (proportional 0.9% of GT), and precision was 1.6 cm (6.3%). M3D’s accuracy of HC was 0.4 cm (1.5%), and precision was 0.7 cm (2.9%). For CrV, M3D’s accuracy was 8.0 mL (3.8%) and precision 22.6 mL (10.8%).ConclusionThe M3D scanner is suitable for measuring HC and CrV in ELBW infants. However, current scan success rate is too low for practical usability. The M3D’s accuracy and precision are clinically sufficient, while the precision of the current measuring tape method is inadequate for preterm infants. This makes the M3D a promising alternative for HC, offering less disturbance to the infant. In the future, the M3D technique could facilitate the creation of CrV growth reference charts for ELBW infants, enhancing the accuracy of clinical growth monitoring for preterm infants.

Mismatches between 3D Content Acquisition and Perception Cause More Visually Induced Motion Sickness

Abstract The sensory rearrangement theory announced that a mismatch between the current visual inputs and the visual exposure history might trigger or aggravate the visually induced motion sickness (VIMS). However, this has not been explicitly investigated through perception experiments. This study investigates the effect of mismatches between 3D content acquisition and perception on VIMS. Two types of mismatches between the camera field of view and the eye field of view were compared with the match type, and the mismatch types are the conditions that configured the camera field of view to be larger or smaller than the eye field of view. A perception experiment was executed with 21 participants, and the subjective SSQ, five-scale VIMS level rating, and objective postural instability were adopted as the evaluation metrics. The mismatches were found to have a significant effect (p < 0.05) on the VIMS symptom based on the results of subjective VIMS level rating and objective postural instability evaluations. Mismatches between 3D content acquisition and perception cause more VIMS. This knowledge highlights the importance of perfect configuration matches in 3D content acquisition, display, and perception for eliminating the potential VIMS aggravation effect.

Integration of Augmented Reality in Temporal Bone and Skull Base Surgeries.

Augmented reality technologies provide transformative solutions in various surgical fields. Our research focuses on the use of an advanced augmented reality system that projects 3D holographic images directly into surgical footage, potentially improving the surgeon's orientation to the surgical field and lowering the cognitive load. We created a novel system that combines exoscopic surgical footage from the "ORBEYE" and displays both the surgical field and 3D holograms on a single screen. This setup enables surgeons to use the system without using head-mounted displays, instead viewing the integrated images on a 3D monitor. Thirteen surgeons and surgical assistants completed tasks with 2D and 3D graphical surgical guides. The NASA Task Load Index was used to assess mental, physical, and temporal demands. The use of 3D graphical surgical guides significantly improved performance metrics in cochlear implant surgeries by lowering mental, physical, temporal, and frustration levels. However, for Bonebridge implantation, the 2D graphical surgical guide performed better overall (p = 0.045). Participants found the augmented reality system's video latency to be imperceptible, measuring 0.13 ± 0.01 s. This advanced augmented reality system significantly improves the efficiency and precision of cochlear implant surgeries by lowering cognitive load and improving spatial orientation.

An Enhanced Multiscale Retinex, Oriented FAST and Rotated BRIEF (ORB), and Scale-Invariant Feature Transform (SIFT) Pipeline for Robust Key Point Matching in 3D Monitoring of Power Transmission Line Icing with Binocular Vision

Power transmission line icing (PTLI) poses significant threats to the reliability and safety of electrical power systems, particularly in cold regions. Accumulation of ice on power lines can lead to severe consequences, such as line breaks, tower collapses, and widespread power outages, resulting in economic losses and infrastructure damage. This study proposes an enhanced image processing pipeline to accurately detect and match key points in PTLI images for 3D monitoring of ice thickness using binocular vision. The pipeline integrates established techniques such as multiscale retinex (MSR), oriented FAST and rotated BRIEF (ORB) and scale-invariant feature transform (SIFT) algorithms, further refined with m-estimator sample consensus (MAGSAC)-based random sampling consensus (RANSAC) optimization. The image processing steps include automatic cropping, image enhancement, feature detection, and robust key point matching, all designed to operate in challenging environments with poor lighting and noise. Experiments demonstrate that the proposed method significantly improves key point matching accuracy and computational efficiency, reducing processing time to make it suitable for real-time applications. The effectiveness of the pipeline is validated through 3D ice thickness measurements, with results showing high precision and low error rates, making it a valuable tool for monitoring power transmission lines in harsh conditions.

Naked-eye 3D visualization of cultural relics based on integrated imaging

AbstractDigital technology has become crucial for the protection of cultural relics, enabling their acquisition, preservation, exhibition, and dissemination in a non-contact manner.At present, the three-dimensional(3D) visualization technology of cultural relics focuses on the research of non-true 3D visualization, which cannot provide continuous viewing angle and takes a long time to render. This paper focuses on the acquisition and reproduction of digital information related to cultural relics, and proposes to achieve the true 3D display of cultural relics from a continuous perspective based on integrated imaging(InIm). Building up on traditional InIm, an Element image array (EIA) generation algorithm based on local depth template matching is designed by using spatial geometry relation. Experimental results show that the algorithm not only enables naked-eye 3D visualization of cultural relics, but also the generation speed is more than twice that of the compared 3D display data source generation algorithm.