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Thin Diffuser Film That Does Not Require Alignment for Local Dimming Mini-LED Display

Thin Diffuser Film That Does Not Require Alignment for Local Dimming Mini-LED Display

Improvements for Automotive LCDs: Image Enhancement and Local Dimming (FALD)

Improvements for Automotive LCDs: Image Enhancement and Local Dimming (FALD)

Role of compressive and tensile strains and spin-orbit coupling on structure and behaviors of cubic FAPbI3 perovskites: A first-principles prediction

Organic-inorganic perovskite materials have attracted significant attention in solar technologies due to their extraordinary structural, electrical, and optical features. This study extensively examined the impacts of bidirectional tensile and compressive strains and spin-orbit coupling (SOC) on the structural, electronic and optical characteristics of formamidinium lead iodide perovskite (FAPbI3) structures. The investigation was performed using the first-principles density-functional theory (DFT). The electronic band structures of FAPbI3 without SOC revealed that the perovskite structure possesses the characteristics of a semiconductor, explicitly featuring a direct bandgap. The application of compressive strains resulted in dwindling the electronic bandgap while tensile strains upsurged the bandgaps, except at +6 % strains. The incorporation of the SOC subjugated a notable decrease in the bandgap, causing a transition of the perovskite structure from a direct bandgap to an indirect bandgap state. The real dielectric constant suggested that the system maintains its semiconducting character under the exposure of both compressive and tensile strains. The imaginary part of the dielectric function, loss spectrum, and absorption coefficient peaks of FAPbI3 perovskites exhibited a blueshift when subjected to compressive strains. However, the application of tensile strains eventuated in a redshift. The electronic and optical characteristics indicated that FAPbI3 perovskites have great potential for optoelectronic devices, including LEDs, LCD backlights, solar cells, lasers, and light detectors.

Bulk CsPbClxBr3-x (1 ≤ x ≤ 3) perovskite nanocrystals/polystyrene nanocomposites with controlled Rayleigh scattering for light guide plate.

Perovskite nanocrystals (PNCs)/polymer nanocomposites can combine the advantages of each other, but extremely few works can achieve the fabrication of PNCs/polymer nanocomposites by bulk polymerization. We originally adopt a two-type ligand strategy to fabricate bulk PNCs/polystyrene (PS) nanocomposites, including a new type of synthetic polymerizable ligand. The CsPbCl3 PNCs/PS nanocomposites show extremely high transparency even the doping content up to 5 wt%. The high transparency can be ascribed to the Rayleigh scattering as the PNCs distribute uniformly without obvious aggregation. Based on this behavior, we first exploit the potential of PNCs to serve as scatters inside light guided plate (LGP), whose surface illuminance and uniformity can be improved, and this new kind of LGP is compatible with the advanced liquid crystal display technology. Thanks to the facile composition adjustment of CsPbClxBr3-x (1 ≤ x ≤ 3) PNCs, the Rayleigh scattering behavior can also be adjusted so as to the performance of LGP. The best-performing 5.0-inch LGP based on CsPbCl2.5Br0.5 PNCs/PS nanocomposites shows 20.5 times higher illuminance and 1.8 times higher uniformity in display than the control. The LGP based on PNCs/PS nanocomposite exhibits an enormous potential in commercialization no matter based on itself or combined with the LGP-related technology.

LGP-YOLO: an efficient convolutional neural network for surface defect detection of light guide plate

Light guide plate (LGP) is a key component of liquid crystal display (LCD) display systems, so its quality directly affects the display effect of LCD. However, LGPs have complex background texture, low contrast, varying defect size and numerous defect types, which makes realizing efficient and accuracy-satisfactory surface defect automatic detection of LGPS still a big challenge. Therefore, combining its optical properties, dot distribution, defect imaging characteristics and detection requirements, a surface defect detection algorithm based on LGP-YOLO for practical industrial applications is proposed in this paper. To enhance the feature extraction ability of the network without dimensionality reduction, expand the effective receptive field and reduce the interference of invalid targets, we built the receptive field module (RFM) by combining the effective channel attention network (ECA-Net) and reviewing large kernel design in CNNs (RepLKNet). For the purpose of optimizing the performance of the network in downstream tasks, enhance the network's expression ability and improve the network’s ability of detecting multi-scale targets, we construct the small detection module (SDM) by combining space-to-depth non-strided convolution (SPDConv) and omini-dimensional dynamic convolution (ODConv). Finally, an LGP defect dataset is constructed using a set of images collected from industrial sites, and a multi-round experiment is carried out to test the proposed method on the LGP detect dataset. The experimental results show that the proposed LGP-YOLO network can achieve high performance, with mAP and F1-score reaching 99.08% and 97.45% respectively, and inference speed reaching 81.15 FPS. This demonstrates that LGP-YOLO can strike a good balance between detection accuracy and inference speed, capable of meeting the requirements of high-precision and high-efficiency LGP defect detection in LGP manufacturing factories.

Preparation and Characterization of Ag Nanoparticle/SiO2 Composite for Optical Application

A facile method to fabricate volumetric light-guide plate (LGP) by micro-nanostructure of Ag/SiO2 composite was presented in this study. The Ag NPs/SiO2 composite were first prepared from a mixture of yellowish-brown Ag NPs colloids and SiO2 powder by electrostatic self-assembly method. Its chemical and physical properties were investigated by scanning transmission microscopy (TEM), scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDX). The small particles (Ag/SiO2 composite) in the LGP could produce multiple scattering effect with different size of micro-nanoparticles, which could improve the light-scattering performance of the LGP. The effective light scattering of the material into LGP was obtained from the increased amount of the particles. Meanwhile, surface plasmon resonance effect of Ag NPs also improves the performance of LGP, which could be further applied to design device in optical application. In additional, optical properties and light scattering mechanism of the Ag NPs/SiO2 composite in the LGP are discussed and presented.

Release Behavior of Liquid Crystal Monomers from Waste Smartphone Screens: Occurrence, Distribution, and Mechanistic Modeling.

Liquid crystal display (LCD) screens can release many organic pollutants into the indoor environment, including liquid crystal monomers (LCMs), which have been proposed as a novel class of emerging pollutants. Knowing the release pathways and mechanisms of LCMs from various components of LCD screens is important to accurately assess the LCM release and reveal their environmental transport behavior and fate in the ambient environment. A total of 47, 43, and 33 out of 64 target LCMs were detected in three disassembled parts of waste smartphone screens, including the LCM layer (LL), light guide plate (LGP), and screen protector (SP), respectively. Correlation analysis confirmed LL was the source of LCMs detected in LGP and SP. The emission factors of LCMs from waste screen, SP, and LGP parts were estimated as 2.38 × 10-3, 1.36 × 10-3, and 1.02 × 10-3, respectively. A mechanism model was developed to describe the release behaviors of LCMs from waste screens, where three characteristics parameters of released LCMs, including average mass proportion (AP), predicted subcooled vapor pressures (PL), and octanol-air partitioning coefficients (Koa), involving coexistence of absorption and adsorption mechanisms, could control the diffusion-partitioning. The released LCMs in LGP could reach diffusion-partition equilibrium more quickly than those in SP, indicating that LCM release could be mainly governed through SP diffusions.

52‐5: Late‐News Paper: Thin and Lightweight Head‐Mounted Displays with Holographic Optics and Polarized Laser Backlights Using an Inverted Wedge‐Shaped Light Guide Plate

Thin and lightweight head‐mounted displays with polarized laser backlights and holographic optics were proposed. To make the distance between the eyes and the displays even shorter, we propose the backlight with an inverted wedge‐shaped light guide plate. We confirmed that it has luminous uniformity and a high degree of polarization.

34‐3: Research on Vehicle mounted Projection Display with Local Dimming Effect

With the development trend of large on‐board screen and intelligent driving, PHUD, as a new type of car head up display application scenario, has gradually attracted the attention of various automobile manufacturers. It greatly simplifies the system design by highlighting modules, specific angle of view steering design, and one‐time windshield projection. At the same time, it carries BD cell Local Dimming technology to achieve exquisite HDR projection display and greatly reduce module drive power consumption, and the contrast can reach millions. This paper mainly studies a module display combining BD cell local dimming and PHUD technology.

P‐114: Novel Optical Simulation System for Pixel Design Optimization

OLED display quality is closely related to pixel design. Usually, in order to evaluate the effect of pixel design on display quality, we need to make panel samples and light them up, or observe killer pattern samples that putted on the back light. Either method costs a considerable amount of time and money. In this paper, we will introuce a novel optical simulation system that we established to evaluate and optimize pixel design qualitatively or quantitatively.

47‐3: In‐Cell Ambient Light Sensors (ALSs) LCD Integration Using a‐Si TFT photo‐transistor and Four‐Mask Process Architecture Technology

We have developed a new AMLCD with multiple ambient light sensors (ALSs) for reducing backlight (BL) power consumption, and false sensing of ambient illuminance. ALSs perform well in showing BL control for power‐saving, even though one of the sensors is covered by a finger shadow. Architecture of integrated ALS with a‐Si technologies are presented. We fabricate the in‐cell and wide‐dynamic‐sensing ALSs display using a‐Si photo‐transistor sensor technology. Photo‐electrical characteristics with well linearity and reliability under long‐term operation were observed.

Designing Freeform Micro Lens Array With Prescribed Luminous Intensity for LCD Backlight Units

Designing Freeform Micro Lens Array With Prescribed Luminous Intensity for LCD Backlight Units

87‐5: AM Mini‐LED Based on LTPS TFT Backplane with over 5000 Dimming Zones and High Driving Bits

LCD with Mini‐LED backlight performs high brightness and high contrast ratio. In this paper novel Mini‐LED based on LTPS TFT backplane is proposed for LCD backlight with over 5000 dimming zones and excellent image quality. Moreover, based on special driving circuit, 12‐14 driving bits, that is 4096‐16384 gray level, is achieved, which can improve local contrast ratio of the image. Compared to PM Mini‐LED, AM Mini‐LED shows superior performance on high dimming zone design, fewer LED drivers and improvement of image quality.

P‐49: Picture Quality Evaluation Method on LCD with Local Dimming Technology †

In this paper, a novel objective evaluation method is proposed to quantify the picture quality. In particular, the effect of “halo” and ‍“backlight delay” is taken into consideration in the design of the evaluation pipeline. The objective evaluation method is used to test ‍the picture quality, and the results are compared with the subjective ones, demonstrating the effectiveness of our proposed evaluation ‍method.

5‐3: Invited Paper: Development of fast LCD with Mini‐LED BLU for VR application

As the market for near‐eye display devices and other similar devices expands, these devices and their display performance are receiving more and more attention and challenges. Therefore, this paper reports a display module consisting of a high PPI fast LCD based on LTPS backplane paired with an ultra‐multi‐partition Mini‐LED backlight. The display adopts a new pixel structure and is able to achieve a transmission rate of 1.8% and a high contrast ratio of 500:1 on 1411 PPI. Besides, the multi‐partition Mini‐LED backlight unit is able to achieve 1728 partitions of local dimming and high dynamic contrast ratio of the display module, meanwhile the brightness of the backlight is increased by 4.9% with the same power consumption, making the overall display module brighter.

42‐4: Automotive Liquid Crystal Display Using mini‐LED Backlight Managed by Flexible Local Dimming System

The automobile industry is entering a period of major transformation. The shift to EVs, autonomous driving, connectivity to networks, etc., suggest the transformation. Along with this, care must be taken to provide passengers with various information. Therefore, the role played by displays will continue to grow in the future. In addition, the shift to EVs forces the demand for reduce of power consumption more and more severe. In this paper, we propose a liquid crystal module suitable for in‐vehicle monitors that combines a mini‐LED backlight system and a flexible control algorithm.

63‐2: Nano‐wire Grid Polarizer and Meta‐surface Textures Integrated High Efficient and Single Polarized Light Emitting Diode

A low power consumption is an essential issue for all of the electrical products, especially for the wearable electrical products, and the liquid crystal displays. This manuscript proposed a single polarized light emitting diode (LED) chip which is used for a direct back light unit for LCD. A wire grid polarizer and a meta‐surface textures are set on the top and bottom of the LED chip in order to obtain a high polarization and transparency. After optimization the potential parameters, the transmittance of TM and the polarization are 93.71% and 99.3% respectively. It can replace the normal LED of direct back light unit in order to obtain a high efficiency of 20% improvement, by comparing liquid crystal display using the APF polarizer. It can be used for reducing power consumption and supply dependence, as well as the cost of displays.

89‐3: Late‐News Paper: High‐Efficiency and Polarized Light Emitting Diode with Wire Grid Polarizer and Meta‐surface Textures

A low power consumption is an essential issue for all of the electrical products, especially for the wearable electrical products, and the liquid crystal displays. This manuscript proposed a single polarized light emitting diode (LED) chip which is used for a direct back light unit for LCD. A wire grid polarizer and a meta‐ surface textures are set on the top and bottom of the LED chip in order to obtain a high polarization and transparency. After optimization the potential parameters, the transmittance of TM and the polarization are 93.71% and 99.3% respectively. It can replace the normal LED of direct back light unit in order to obtain a high efficiency of 20% improvement, by comparing liquid crystal display using the APF polarizer. It can be used for reducing power consumption and supply dependence, as well as the cost of displays.

Latest Advances in Narrow‐Band Phosphors and Their Role in Color Management

Latest Advances in Narrow‐Band Phosphors and Their Role in Color Management

P‐17.4: Research On High‐performance Of Automotive BDCELL Module

The BOE BDCELL technology has been suc cessfully applied to automotive display. It is essentially a dual‐cell display technology: The color cell is for d isplay, the mono cell is for backlight, and the back lig ht is still common edge type. In this paper, the perfor mance of BDCELL products is further optimized based on the actual application scenarios of the vehicle: incl uding the pixel design of dual‐cell, contrast ratio enhan cement, halo optimization, ghost optimization, large vie w image quality optimization, and EMC performance o ptimization. It can be applied directly to vehicle displa y to provide users safer and better driving experiences.