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We develop a new OLED/organic photodetector dual‐mode device, which enables OLED subpixels to capture the image of an object on a screen. The proposed device can be employed in an OLED display without changing the aperture ratio and pixel density of the display. [ABSTRACT FROM AUTHOR]

This study presents the fabrication of a 513‐ppi organic light‐emitting diode (OLED) display featuring an integrated organic photodiode (OPD) within each pixel, eliminating the need for a fine metal mask. The fabrication process involves photolithography for the side‐by‐side patterning of OLED and OPD subpixels, leading to a four‐subpixel configuration. This configuration incorporates an OPD subpixel into each pixel while preserving the high resolution of OLED subpixels. The outcome is the successful development of an active panel capable of both high‐resolution display and imaging, boasting a high aperture ratio. [ABSTRACT FROM AUTHOR]

Interval timing—the perception of durations mainly in seconds or minutes—is a ubiquitous behavior in organisms. Animal studies have suggested that the hippocampus plays an essential role in duration memory; however, the memory processes involved are unclear. To clarify the role of the dorsal hippocampus in the acquisition of long‐term duration memories, we adapted the "time‐shift paradigm" to a peak‐interval procedure. After a sufficient number of training with an initial target duration (20 s), the rats underwent "shift sessions" with a new target duration (40 s) under a muscimol (0.5 µg per side) infusion into the bilateral dorsal hippocampus. The memory of the new target duration was then tested in drug‐free "probe sessions," including trials in which no lever presses were reinforced. In the probe sessions, the mean response rate distribution of the muscimol group was located leftward to the control group, but these two response rate distributions were superimposed on the standardized time axis, suggesting a scalar property. In the session‐by‐session analysis, the mean peak time (an index of timing accuracy) of the muscimol group was lower than that of the control group in the probe sessions, but not in the shift sessions. These findings suggest that the dorsal hippocampus is required for the formation of long‐term duration memories within the range of interval timing. [ABSTRACT FROM AUTHOR]

We fabricated a prototype display that incorporates an organic image sensor in the same pixel as OLEDs through side‐by‐side patterning. The display enables fingerprint image capturing and scanning at any location on the entire display region. We fabricated a flexible OLED display with the aforementioned structure. [ABSTRACT FROM AUTHOR]

We have developed a display that incorporates an organic image sensor formed in the same pixel as OLEDs through side‐by‐side patterning. The potential applications of this display include touch sensing, scanning, and fingerprint identification at any location on the entire display screen, without the necessity of an external module. [ABSTRACT FROM AUTHOR]

This study aims to focus on a cover film with a considerably low Young's modulus to achieve robust and flexible displays. We fabricated a prototype flexible display with such a film on its surface and achieved a display with robustness and bendability, which can be used in various applications. [ABSTRACT FROM AUTHOR]

This paper introduces and demonstrates a display that incorporates an organic image sensor formed in the same pixel as organic light‐emitting diodes through side‐by‐side patterning. The potential applications of this display include touch sensing, scanning, and fingerprint identification at any location on the entire display screen, without the necessity of an external module. [ABSTRACT FROM AUTHOR]

We have developed a top‐emission organic light‐emitting diode (OLED) Kawara‐type multidisplay with a novel auxiliary electrode. With this device, while the contact portion of the auxiliary electrode is developed in the display region, a high aperture ratio can be achieved. This technique can be utilized in any top‐emission OLED display. [ABSTRACT FROM AUTHOR]

Viewing angle performance of flexible organic light-emitting displays (FOLEDs) with red-green-blue (RGB) side-by-side (SBS) architecture plays a major role in the visual appearance in the curved state. In particular, viewing the display from a central-normal vantage point, the color shift becomes visible when viewing the bent edges of the display. The viewing angle performance of a color-by-white FOLED was measured goniometrically and compared with a SBS FOLED. [ABSTRACT FROM AUTHOR]

Phosphorescent organic‐light emitting diodes (PHOLEDs) exhibit an internal quantum efficiency of 100% and their early practical realization is expected. One of the main challenges in PHOLEDs is to improve the operational stability of green and blue devices. Triplet exciton dynamics in stable PHOLEDs, which are different from those in unstable PHOLEDs, are shown. An efficient and stable green PHOLED is demonstrated by employing a suitable host that surrounds the phosphorescent dopant. The transient photoluminescence characteristics show that the triplet excitons of the host, which are generally unstable, are rapidly transferred to the dopant and emit phosphorescence in the stable PHOLED. Most of the triplet excitons of the host in the stable PHOLED are transferred to the dopant within 10 ns, following the Förster process by utilizing reverse intersystem crossing from the triplet state to the singlet state. The findings also provide a design strategy for hosts to enable realization of highly stable full‐color PHOLEDs. [ABSTRACT FROM AUTHOR]

We examined the hole-transporting-material (HTM)-dependent device characteristics of green phosphorescent organic light-emitting diodes (PHOLEDs) using an electron-transporting host. The emission efficiency of the PHOLEDs was proportional to the optical band gap and the triplet energy of the HTMs. On the other hand, the operational stability of the PHOLEDs was not proportional to the emission efficiency. By analyzing the device characteristics in relation to the molecular structure of HTMs, amine derivative with dibenzothiophene was found to be effective HTMs suitable for highly efficient and stable green PHOLEDs. [ABSTRACT FROM AUTHOR]

Organic light-emitting diodes (OLEDs) have been intensively studied as a key technology for next-generation displays and lighting. The efficiency of OLEDs has improved markedly in the last 15 years by employing phosphorescent emitters. However, there are two main issues in the practical application of phosphorescent OLEDs (PHOLEDs): the relatively short operational lifetime and the relatively high cost owing to the costly emitter with a concentration of about 10% in the emitting layer. Here, we report on our success in resolving these issues by the utilization of thermally activated delayed fluorescent materials, which have been developed in the past few years, as the host material for the phosphorescent emitter. Our newly developed PHOLED employing only 1 wt% phosphorescent emitter exhibits an external quantum efficiency of over 20% and a long operational lifetime of about 20 times that of an OLED consisting of a conventional host material and 1 wt% phosphorescent emitter. [ABSTRACT FROM AUTHOR]

We report on the energy transfer mechanism between the host and the iridium dopant in phosphorescent organic light-emitting diodes (PHOLEDs). The excited-state energies of the host and the dopant are carefully defined to discuss the energy transfer. The PHOLED using bis(benzo[h]quinolin-10-olato-kN,kO)beryllium(II) (Bebq2) as the host and bis(4-pentafluorophenyl-2-phenylpyridine)(acetylacetonate)iridium(III) (m-PF-py) as the dopant shows a maximum external quantum efficiency (ηext) of about 15%, whereas the photoluminescence quantum yield of the emitting layer film is only 19%. The high ηext of the PHOLED implies efficient triplet–triplet energy transfer from Bebq2 to m-PF-py. [ABSTRACT FROM AUTHOR]