Journal of the Society for Information Display最新文献

Emerging micro light-emitting diode (microLED) displays promise high brightness, improved lifetime, and high pixel density. However, to achieve the desired color accuracy, microLEDs require constant current driving, which can result in wavelength shift at higher pixel brightness. This presents a challenge for pixel circuit design. The driving scheme must vary the emission duration (i.e., pulse width modulation, PWM) to prevent wavelength shift, and it must also include an element of current magnitude control (pulse amplitude modulation, PAM) for fine tuning. This results in complex signaling, large footprint, and multiple sources of variability arising from the numerous transistors, which together diminish the implementation's efficacy. Here, we present a 6T1M2C pixel circuit, which takes advantage of the properties of the multimodal thin-film transistor (MMT) to achieve PWM and PAM simultaneously, rather than in a hybrid configuration, while also performing threshold compensation. The MMT is the first transistor that allows for separation of injection (current magnitude) from channel conduction state (timing), allowing a higher degree of freedom for designing pixel circuits with lower complexity. This proof-of-concept TCAD implementation demonstrates the benefits of MMT-based simultaneous PWM and PAM circuits, with compact device footprint, reduced circuit complexity, and power-efficient features.

Virtual reality (VR) displays aim to create highly immersive virtual environments based on the principle of binocular disparity, which reproduces spatial information of virtual scenes through the fusion processing of binocular disparity by the visual system. However, due to the differences between VR displays and real-world scenes, the challenge of rendering in VR displays in a manner that aligns with users' natural depth perception principles has not been fully addressed. In this paper, the virtual image distances (VIDs) of RGB channels in head-mounted display (HMD) were measured and a depth perception experiment based on random dot stereograms (RDS) according to the measured VID values was designed. The depth perception comfort fusion thresholds in VR systems were determined by psychophysical methods, and the results demonstrate that the comfort fusion threshold for uncrossed disparity is significantly lower than that for crossed disparity. Additionally, user interaction performance in the determined virtual depth scenarios showed a 12.94% reduction in reaction time and a 16.86% improvement in accuracy compared to other virtual depths. Our findings provide further understanding of comfortable depth visual presentation in VR displays, which is crucial for enhancing user experience and promoting the widespread adoption of VR technology across various applications.

OLEDs are playing an important role in flexible displays, smart wearable, in-vehicle displays, and other fields. Foldable OLED panels consist of multiple layers of film. To ensure the reliability, some key films such as the OLED should be placed on the neutral plane, which is usually achieved by adjusting the thickness of each layer. In this paper, genetic algorithm is introduced to find the optimum configurations of the thickness of each layer. Based on the mathematical express of the stress happening on each film when an OLED panel is folded, the objective function can be defined and the optical thicknesses of some layers can be got. The simulation results show that with such optical thickness configuration, the stresses on key films can effectively reduce. The method proposed in the paper can help improve the folding performance of a foldable OLED panel.

Ultrafast liquid crystal light valves are extensively utilized in high-refresh-rate displays and light beam control and shaping applications. Ferroelectric liquid crystals, characterized by their ability to achieve microsecon response times when driven by a 5 V voltage, are particularly well-suited for array-type liquid crystal light valves, such as display screens or adjustable liquid crystal gratings. This study employs optimized ferroelectric liquid crystal materials that exhibit high contrast (~1,000:1), ultra-fast response times (<20 μs), and polarity-dependent binary switching at low operating voltages (5 V) to develop an array liquid crystal light valve suitable for time-sequential light field 3D displays. Combined with high frame rate display screen, a naked eye 3D display without resolution loss can be achieved. The challenges associated with the independent control of ferroelectric liquid crystals during array light valve operation were analyzed and resolved, resulting in an array-type ultrafast ferroelectric liquid crystal light valve compatible with conventional liquid crystal driving schemes.

Object color coverage by output media is necessary to understand the limitations of color reproduction. However, complex shapes exhibited in 3D color spaces can pose challenges. Even if their 3D plot axes are rotated, their shape and size is generally difficult to understand. In this study, the color gamuts of both real and theoretical objects were selected as reference gamuts and compared with a few standard trichromatic color spaces using gamut rings—a 2D visualization method that allows quantification of color capabilities across lightness, chroma, and hue ranges. Additionally, gamut intersections between the standard color spaces and reference object color gamuts were represented proportionally on the rings to facilitate a straightforward evaluation of the color capabilities of the standard color gamuts.

The 2023 Nobel Prize in Chemistry was awarded to Aleksey Yekimov, Professor Louis Brus, and Professor Moungi Bawendi for their pioneering work in the discovery and synthesis of quantum dots (QD). QDs have become a major materials component of modern displays, initially in commercial LCD products starting in 2013 and more recently in a new generation of QD-OLED TVs. The Nobel Prize was given largely for chemistry work done up to and including the 1990s, when LCD TV displays still were a technology of the future. In this review, we will explore three moments in history that led to the current QD commercial display age built on the foundation of the magnificent science of the 1990s that led to the 2023 Nobel Prize in Chemistry.

As one of the key components of liquid crystal display, the quality of the hot-pressed light guide plate (LGP) directly affects the display performance. To address the challenges posed by complex background textures, diverse types of defects, large variations in defect resolutions, and low contrast, this paper proposes a surface defect detection method for hot-pressed LGPs based on the PR-YOLOv9. The poly kernel inception network (PKINet) module is integrated by replacing the second convolution module of the YOLOv9 backbone network, effectively reducing interference from invalid targets such as complex textured backgrounds, thereby enhancing the network's ability to detect multi-scale defects and decreasing the network's parameters. Additionally, the receptive-field attention convolutional operation (RFAConv) module is incorporated, replacing the first and last layers of the YOLOv9 backbone network with this module. RFAConv module provides attention weights for large convolution kernels, effectively improving the network's ability to extract spatial feature information. Experimental results show that the proposed PR-YOLOv9 network achieves a mean average precision (mAP) of 98.40% and F1-Score of 97.14% on a self-constructed hot-pressed LGP defect dataset, with a reduction of 6.19 M in network parameters compared with YOLOv9, representing a decrease of 10.18%, making it suitable for real-time detection in industrial settings.

This study explores the application of lift-off process for the patterning of quantum dot (QD) pixels using CdSe/ZnS core-shell colloidal QDs. The evaluation of the influence of different solvent and binder systems on the effectiveness of the pixelation is detaily discussed. By optimizing the solvent and binder combination, the fabrication of multi-color QD patterns with pixel sizes ranging from 5 to 200 μm were demonstrated, achieving blue light conversion efficiencies exceeding 18% and 25% for red and green pixels. It is also improved pixel uniformity, stability, and resolution, lying the foundation for the development of ultra-high-resolution, QD Micro-LED display. However, challenges remain in maximizing the utilization of blue light and packaging of QD layers. Future research will aim to develop high-quality QD inks suitable for photoresist lift-off and optimize the QD Micro-LED system to further enhance the performance and stability of QD-based displays.

Hybrid silicon and lithium niobate (LN) photonic integration platform has emerged as a promising candidate to combine the scalability of silicon photonic with the high modulation performance of LN. With the rapid development of virtual reality, data communication, and high-definition video, the core optical modulator has been upgraded to ultrahigh-bandwidth (BW) and low half-wave voltage ($�V_{\pi }$). Low $�V_{\pi }�$ and high-BW LN modulators have been demonstrated, with applications ranging from microwave photonics to quantum interfaces. However, due to the simulation design, material selection, and preparation process, the values of BW and voltage are not satisfactory, whose $�V_{\pi }$ of 2.2 V and BW of 67 GHz indicators are not excellent. We successfully prepared monolithically integrated TFLNM that feature a CMOS-compatible bias voltage, support data rates up to 110 GHz and half-wave-voltage down to 2 V. We achieve this by designing high BW and low voltage, high-quality preparation, advanced testing, and characterization platform. Notably, the results from physical objects align closely with those from Lumerical INTERCONNECT simulations. Overall, our study has almost doubled the BW of TFLNM reported so far, and $�V_{\pi }�$ has decreased from 2.2 to 2 V.

Images drawn in the air will be effective for the projection of a person or an avatar in telecommunication and man–machine communication. Direct drawing with femtosecond laser pulses can generate images anywhere without any special materials; therefore, there are fewer restrictions on image display location. The biggest challenge in research and development is to increase the display size. To increase the display size, it is necessary to make the objective lens have a longer focal length (lower numerical aperture), but increasing the focal length is accompanied by a decrease in excitation efficiency due to an increase in the focused size. Therefore, by measuring the luminous intensity and luminous size using lenses with several focal lengths, the possibility of realizing a display with a centimeter-sized (fist-sized) volume using a lens with a focal length of 100 mm was found. By reconstructing the optical system of the aerial volumetric display using a lens with a focal length of 100 mm, a drawing range of 68 mm on average in the lateral direction and 42 mm in the axial direction was achieved.