Journal of the Society for Information Display最新文献

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.

As electronic displays have become to be used under ambient illumination environment, the situations have been increased which the screens are exposed to the various types of ambient light sources. Since the reflection of ambient light by the screen generally results in the lack of visibility of the displayed contents, anti-glare layer (AGL) on top of the screen has been applied to suppress unwanted reflection. Meanwhile, handheld digital devices have been actively adopted to enhance the quality of learning experiences. Although it was pointed out that the impact of glare may lead to shorter viewing distance or poor posture of the students, there was not enough information regarding the relation between writing and optical characteristics of the anti-glare screen. The purpose of this study is to provide information, which will help to select the appropriate screens for each application. Through the experiments with different AGLs and the displays, coefficient of friction, gloss value, sparkle contrast, and display modulation transfer function (MTF) were selected to characterize the writing and the optical characteristics. While the trend of the gloss values was similar to that of the display MTF, the trend of the sparkle contrast was different from them. These results were summarized as radar charts.

Tiling with a variety of panel units is a promising approach to customizing displays in terms of size, shape, and aspect ratio. However, tiled displays with conventional panel units have a major drawback in that they suffer from noticeable seams due to the bezels of the panel units. Here, we demonstrate a flexible bezel-less thin-film transistor (TFT) backplane for seamless tiling. By using through-plastic-vias (TPVs) that penetrate an ultrathin polyimide (PI) film substrate, a bezel-less backplane with an ultra-narrow bezel width of 8 μm was realized, in which oxide TFTs in pixel circuits on the backplane are driven from the back side of the PI film substrate using three-dimensional signal wires, which go through the TPVs. The resistance of a TPV was evaluated with a TPV chain with 1000 TPVs connected in series and was found to be as small as 1.3 Ω. Furthermore, the transfer characteristics of an oxide TFT in a test element group for a pixel circuit were evaluated from the back side of the PI film substrate. The TFT exhibited clear switching behavior with an on/off current ratio of more than 10⁸ and a high mobility of 25 cm²/Vs, which are sufficient to drive light-emitting devices.

We propose a novel diffuser film structure designed for mini-LED backlights. The proposed film is composed of a multilayer dielectric and a microprism layer. The dielectric layers function as an angle filter that does not transmit blue light directly above the LED and only transmits blue light with an incident angle above a designed value. The microprism layer controls the direction of the LED light and replicates the LED lights laterally. This combination of angle filter and microprism layer makes the illuminance distribution uniform without requiring alignment between the LED chips and the diffuser film. Our proposed diffuser film provides 4× better efficiency, better uniformity than conventional films, and only 50 μm thickness.

High-power blue-emitting laser diodes have been used in projectors and lighting systems as excitation sources for yellow-emitting phosphors. These phosphors must be robust and should not exhibit thermal quenching. In this work, we developed a durable eutectic phosphor consisting of single-crystal Ce-doped yttrium aluminum garnet (Ce:YAG) phosphor and Al₂O₃ (sapphire), with a thermal conductivity greater than 20 W/(m·K). This eutectic phosphor is named EPOCH-Neo. EPOCH-Neo specimens were cut from a large crystal substrate prepared by an edge-defined film-fed growth method. We evaluated the optical properties of EPOCH-Neo specimens and the optical uniformity of an EPOCH-Neo substrate. In addition, to control the chromaticity, the Y-sites of Ce:YAG were doped with Gd at concentrations as high as 50% and the chromaticity and thermal characteristics of the resultant phosphors were evaluated. Moreover, the characteristics of a device composed of EPOCH-Neo on a heatsink under blue laser excitation were examined. The results showed that EPOCH-Neo is a durable phosphor suitable for use in high-power-excitation applications.

We developed a patterning technology using photolithography that eliminates the need for a fine metal mask, thereby achieving high resolution across all red-blue-green pixels of an organic light-emitting diode (OLED) display. Traditional methods using fine metal masks typically restrict the resolution and size of a display. However, the proposed technology largely bypasses these constraints. Suitable for OLED applications ranging from microdisplays in augmented reality and virtual reality to large TVs exceeding 80 in., our technology overcomes limitations on alignment accuracy, fine metal mask washing, and running costs and paves the way for mass production in OLED manufacturing.

Monte Carlo ray tracing can produce high-fidelity stereo renderings of 3D scenes. However, the computational costs associated with shading indirect illumination can be prohibitively expensive. While techniques like reprojection and reconstruction have been employed to reduce the inherent redundancy in stereo rendering, they often fall short in addressing issues like remaining holes and appearing artifacts, particularly in the case of specular reflections. In this paper, we introduce a stereo rendering method that leverages both ray tracing and 3D warping, incorporating techniques for reusing indirect illumination calculations and perception-driven reconstructions. At the pre-rendering stage, we reuse indirect illumination calculations in the background and 3D warping regions, resulting in significant savings of indirect illumination calculations in the testing scenes. For the remaining holes, we adopt a sparse sampling strategy for representative pixels, guided by saliency maps. We iteratively reconstruct indirect illumination, employing a stopping criterion based on just noticeable difference thresholds. Through equal-sample experiments, we showcase the efficiency achieved by the proposed method in reducing high-level sampling costs for 87.688% ~ 99.581% regions of the test scenes. Furthermore, the proposed method excels in accurately rendering both diffuse and specular reflections, ultimately enhancing the overall visual perception quality.

We review the literature and relevant standards related to image quality characterization of medical devices using near-eye displays (NEDs). First, we discuss the experimental considerations for NED measurements and the methods for aligning the light measuring device (LMD) to the NED. Second, we discuss measurement methods for several critical image quality characteristics, namely luminance, contrast, spatial resolution, geometrical distortion, and spatiotemporal properties including the methods' limitations. These characteristics were selected due to the importance of medical device NED applications. Finally, modeling methods for image quality of NEDs are discussed. Accurate and reproducible evaluation methods for image quality are essential for the safe and effective adoption of augmented and virtual reality NEDs into medical applications.

Quantum dots (QDs) are important luminescent structures with applications in wide-color-gamut displays requiring exceptional color reproducibility. Multinary semiconductor QDs are expected to serve as eco-friendly materials to replace conventional QDs owing to the narrow spectral widths and tunable bandgaps of these QDs. However, the application of multinary QDs, which tend to exhibit defect-related emissions, to QD light-emitting diode (QLED) displays will require electroluminescence to be obtained from QLEDs incorporating inkjet-printed emitting layers. The present work examines QLEDs exhibiting vibrant color emissions based on blue-emitting Zn–Se–Te QDs, green-emitting Ag–In–Ga–S QDs, and red-emitting Ag–Cu–In–Ga–S QDs. Each such QLED contains QD emitting layers comprising a mixture of charge transport materials. The spectra obtained from these RGB QLEDs fabricated by spin-coating show very high color purity. Passive matrix QLED displays incorporating these QDs are also fabricated by inkjet printing to demonstrate the high color purity that can be obtained from multinary QDs in displays. In conjunction with passive matrix driving, these displays produce clear moving images with vibrant electroluminescence originating from the multinary QDs. The present results indicate that these QDs have significant potential for utilization in wide-color-gamut displays.