We propose a large parallax barrier by use of aperture grille. Main advantages of using aperture grille include no reflection and no absorption in apertures, as well as wide viewing angle. These advantages are investi...We propose a large parallax barrier by use of aperture grille. Main advantages of using aperture grille include no reflection and no absorption in apertures, as well as wide viewing angle. These advantages are investigated with theoretical calculations and experiments by use of several kinds of LED panels, such as a fine-pitch LED panel and a 140-inch large LED panel. Limitations of viewing angle by parallax barrier are analyzed in conventional black stripes on a transparent substrate type and in aperture grille type. Experimental results straw use of aperture grille increases contrast and reduce reflection on the aperture surface.展开更多
给出了一个基于C PL D/FPG A设计的软件模块化L E D显示电路.通过串行扫描方式驱动LE D数码管,可较少地占用可编程器件资源;并利用M A X P LU S II对动态扫描L E D显示电路进行仿真.最后,对动态扫描显示下数码管的亮度降低的原因进行分...给出了一个基于C PL D/FPG A设计的软件模块化L E D显示电路.通过串行扫描方式驱动LE D数码管,可较少地占用可编程器件资源;并利用M A X P LU S II对动态扫描L E D显示电路进行仿真.最后,对动态扫描显示下数码管的亮度降低的原因进行分析,认为采用降低扫描频率,增大脉冲光对人眼的作用时间和增大驱动电流来提高LE D显示器亮度.展开更多
Deterministic assembly techniques that enable programmatic and massively parallel integration of chips are essential for the development of novel electronic systems such as micro LED displays.However,large-area integr...Deterministic assembly techniques that enable programmatic and massively parallel integration of chips are essential for the development of novel electronic systems such as micro LED displays.However,large-area integration of ultrathin micro-chips with high yield and transfer accuracy remains a great challenge due to the difficulties in selective transfer,adhesion switchability,and transfer deviation.Here,a“laser projection proximity transfer(Laser PPT)”technique is presented for the deterministic assembly of microchip arrays at scale.One of the remarkable features is that the transfer status between the chip and the receiver substrate evolves from the original non-contact mode to contact mode for high-precision transfer,which overcomes the strict requirements of the flatness of stamp and substrate in contact-style transfer,and flight deviation of microchip array in noncontact-style transfer.Another feature is the rapid modulation of interfacial adhesion for reliable transfer via the use of thermally expandable microspheres to form microstructures and combining with a laser-induced blister.The adhesion regulation range is over 20 times without any damage to chip arrays.The results show that the transfer accuracy has been improved substantially with a minimum relative error of~0.5%.Combined with a laser beam projection system,demonstrations of Laser PPT for selective assembly of fragile objects onto challenging non-adhesive/cured surfaces in batch illustrate its potential in the highprecision integration of microscale chips at scale.展开更多
Advances in image quality in recent decades have made it necessary to develop new technologies for producing displays to meet remarkably stricter standards. The display market is governed mainly by liquid crystal disp...Advances in image quality in recent decades have made it necessary to develop new technologies for producing displays to meet remarkably stricter standards. The display market is governed mainly by liquid crystal display and light-emitting diode （LED） technology; however, it suffers from limitations that can be overcome by developing the next generation of electroluminescent displays. The introduction of colloidal quantum dots （QDs） as down-converters has enabled the production of displays with extremely high color purity and gamut. Therefore, colloidal nanocrystals are excellent candidates for the preparation of electroluminescent devices, which represent a straightforward approach to the development of unprecedented high-quality displays. We synthesized light-emitting QDs covering the entire visible spectrum with high fluorescence quantum yields and color purity, and produced high-brightness single-color LEDs with external quantum efficiencies of 0.39%, 1.04%, 2.10%, and 1.30% for red-, orange-, green-, and blue-emitting dots, respectively. Additional136 white LEDs were prepared by mixing QDs; they showed color temperatures of 5,300 K and color rendering indices exceeding 80%. Very importantly, we exhaustively characterized the LED performance, including the response time, stability, and evolution of the light characteristics, thus providing crucial information toward the development of high-quality electroluminescent displays.展开更多
文摘We propose a large parallax barrier by use of aperture grille. Main advantages of using aperture grille include no reflection and no absorption in apertures, as well as wide viewing angle. These advantages are investigated with theoretical calculations and experiments by use of several kinds of LED panels, such as a fine-pitch LED panel and a 140-inch large LED panel. Limitations of viewing angle by parallax barrier are analyzed in conventional black stripes on a transparent substrate type and in aperture grille type. Experimental results straw use of aperture grille increases contrast and reduce reflection on the aperture surface.
文摘给出了一个基于C PL D/FPG A设计的软件模块化L E D显示电路.通过串行扫描方式驱动LE D数码管,可较少地占用可编程器件资源;并利用M A X P LU S II对动态扫描L E D显示电路进行仿真.最后,对动态扫描显示下数码管的亮度降低的原因进行分析,认为采用降低扫描频率,增大脉冲光对人眼的作用时间和增大驱动电流来提高LE D显示器亮度.
基金supported by the National Natural Science Foundation of China(Grant Nos.51925503,52188102,and 52105576)the Natural Science Foundation of Hubei Province of China(Grant No.2020CFA028)。
文摘Deterministic assembly techniques that enable programmatic and massively parallel integration of chips are essential for the development of novel electronic systems such as micro LED displays.However,large-area integration of ultrathin micro-chips with high yield and transfer accuracy remains a great challenge due to the difficulties in selective transfer,adhesion switchability,and transfer deviation.Here,a“laser projection proximity transfer(Laser PPT)”technique is presented for the deterministic assembly of microchip arrays at scale.One of the remarkable features is that the transfer status between the chip and the receiver substrate evolves from the original non-contact mode to contact mode for high-precision transfer,which overcomes the strict requirements of the flatness of stamp and substrate in contact-style transfer,and flight deviation of microchip array in noncontact-style transfer.Another feature is the rapid modulation of interfacial adhesion for reliable transfer via the use of thermally expandable microspheres to form microstructures and combining with a laser-induced blister.The adhesion regulation range is over 20 times without any damage to chip arrays.The results show that the transfer accuracy has been improved substantially with a minimum relative error of~0.5%.Combined with a laser beam projection system,demonstrations of Laser PPT for selective assembly of fragile objects onto challenging non-adhesive/cured surfaces in batch illustrate its potential in the highprecision integration of microscale chips at scale.
文摘Advances in image quality in recent decades have made it necessary to develop new technologies for producing displays to meet remarkably stricter standards. The display market is governed mainly by liquid crystal display and light-emitting diode （LED） technology; however, it suffers from limitations that can be overcome by developing the next generation of electroluminescent displays. The introduction of colloidal quantum dots （QDs） as down-converters has enabled the production of displays with extremely high color purity and gamut. Therefore, colloidal nanocrystals are excellent candidates for the preparation of electroluminescent devices, which represent a straightforward approach to the development of unprecedented high-quality displays. We synthesized light-emitting QDs covering the entire visible spectrum with high fluorescence quantum yields and color purity, and produced high-brightness single-color LEDs with external quantum efficiencies of 0.39%, 1.04%, 2.10%, and 1.30% for red-, orange-, green-, and blue-emitting dots, respectively. Additional136 white LEDs were prepared by mixing QDs; they showed color temperatures of 5,300 K and color rendering indices exceeding 80%. Very importantly, we exhaustively characterized the LED performance, including the response time, stability, and evolution of the light characteristics, thus providing crucial information toward the development of high-quality electroluminescent displays.
