The light output of dipole source in three types light‐emitting diodes (LEDs), including the conventional planar LED, nanorod and localized surface plasmon (LSP) assisted LED by inserting silver nanoparticles gaps between nanorods, was studied use two‐dimensional finite difference time domain method. height size were variables for discussion. Simulation results show that a large induces strong wavelength selectivity, which can be significantly enhanced LSP. On condition is 400 nm, diameter...

We design and fabricate a low-loss silicon photonic two-dimensional grating coupler that serves to couple light between standard single-mode fibers waveguides in the silicon-on-insulator platform split both orthogonal polarization states. The efficiency of fabricated device is enhanced by backside metal mirror reaches record value -1.8 dB with 1 bandwidth 32 nm around 1550 nm. demonstrated coupling 2.2 better than conventional without mirror.

Abstract The pursuit of advanced illumination and display technologies has driven the development beam manipulation for GaN micro-sized light-emitting diodes (LEDs). To realize an efficient polarization emission light source, we propose metasurface-integrated resonant cavity (RCLEDs), incorporating a dual-layer embedded photonic crystal (PhC) within cavity, placing resonant-cavity reflector (RCR) on top existing distributed Bragg (denoted as PhC-RCR-RCLED). Numerical simulations reveal...

The pursuit of perfection has become a common job requirement for modern organizations against the backdrop increasingly fierce market competition. Drawing upon appraisal theory emotion, we develop and test model delineating paradoxical role that leader perfectionism plays in predicting employee's performance. Specifically, propose improves performance through increased harmonious work passion simultaneously hinders it enhanced pressure. We further self-efficacy as boundary condition, such...

Oudemansiella raphanipes is valued for its rich nutritional content and medicinal properties, but traditional manual grading methods are time-consuming labor-intensive. To address this, deep learning techniques employed to automate the process, knowledge distillation (KD) used enhance accuracy of a small-parameter model while maintaining low resource occupation fast response speed in resource-limited devices. This study employs three-teacher KD framework investigates three cascaded...

The white light‐emitting diode (LED) modules, in which the GaN‐based blue‐LED chip with 4 × arrayed pixels are packaged chip‐on‐board technique and welded on a print circuit board, fabricated for both illumination visible light communication (VLC). effects of mesa size characteristic features explored. It shows that small can sustain high saturated current density. Under density, highest luminous flux 278.4 lm be obtained by using largest pixel 160 µm‐diameter, or 3‐dB modulation bandwidth...

Green resonant-cavity light-emitting diode (RCLED) has great potential in optical communication but suffers low efficiency. In this study, GaN-based flip-chip green RCLED incorporated with nitrogen face-oriented inclination asymmetric trapezoidal quantum wells (NOAT-QWs) is proposed to enhance the light-output power (LOP). Samples NOAT-QWs and normal symmetric square (SS-QWs) were fabricated characterized. Although their electrical characteristics emission spectra are similar, LOP efficiency...

To optimize the uniformity of signal-to-noise ratio (SNR) distribution in a visible light communication (VLC) system, firefly algorithm is improved for joint optimization location, power allocation and orientation light-emitting diode (LED) lamp array. Taking 16 LED lamps as an example, optimizations with different number degrees-of-freedom (DOF) are investigated. The orientation-involved significantly decrease average SNR illuminance. However, if illuminance restricted to large value,...

The quantum dot (QD) light-emitting diode (LED) is a robust scheme for single photon source. However, the spontaneous emission of QD LED has arbitrary directions and polarizations, which disadvantage collection manipulation. We propose integrated with an Ag grating phase-gradient metasurface. circular patterned adopted to collimate beam right phase improve its spatial coherence, therefore metasurface can work 10°, 20°, 30° angle deflection as well doughnut-pattern generation are demonstrated...

As a traditional edible and medicinal fungus in China, Oudemansiella raphanipes has high economic benefits. In order to achieve the automatic classification of into four quality levels using their image dataset, grading algorithm based on neural network models was proposed. At first, transfer learning strategy six typical convolution models, e.g., VGG16, ResNet50, InceptionV3, NasNet-Mobile, EfficientNet, MobileNetV2, were used train datasets. Experiments show that MobileNetV2 good...

Near-ultraviolet (NUV) light-emitting diodes (LEDs) have been used in several potential applications such as UV curing and biochemical sensors. However, the internal quantum efficiency (IQE) of NUV-LEDs is still a crucial issue. To improve IQE, this paper, an asymmetric triangular multiple well (MQW) structure was used, which exhibited higher emission lower droop with nitrogen face-oriented inclination. This contrast to trend observed blue LEDs. Furthermore, we demonstrated that holes are...

Three types of textured indium-tin-oxide (ITO) surface, including nano-texturing and hybrid micro/nano-texturing with micro-holes (concave-hybrid-pattern) or micro-pillars (convex-hybrid-pattern), were applied to GaN-based light-emitting diodes (LEDs). The was realized by maskless wet-etching, the micro-texturing achieved standard photolithography wet-etching. Compared LED chips flat ITO those nano-pattern, concave-hybrid-pattern, convex-hybrid-pattern exhibit enhancement 11.3%, 15.8%,...

GaN‐based top‐emitting micro‐blue‐light‐emitting diode chips with different current spreading layers (CSLs) and sizes are fabricated, analyzed at ambient temperatures, their performances compared. The observed behaviors attributed mainly to the thermal effects, determined by temperature internal heat from injected current. For any chip size temperature, an indium tin oxide (ITO) CSL induces higher light‐output power (LOP) external quantum efficiency (EQE), making it better choice in...

We develop a design theory for temperature-independent arrayed waveguide grating (TI-AWG) based on the combination of multiple types waveguide. Each type has path-length difference between adjacent waveguides, and ratio is introduced as tuning parameter. A TI-AWG with Si wire slot waveguides given an example. The thermal spectra shift can be tuned from redshift to blueshift in ultralarge range, modified interference order reduced or enhanced. device size about one-fifth that narrow-wide-wire...

Abstract A new design of temperature-independent Mach–Zehnder interferometer (MZI) based optical filter involving a combined use silicon (Si) wire waveguides and slot is presented. The ratio the path-length difference for two types introduced to tune thermal performance filtering wavelength. This its derived parameters render high-level flexibility optimizing interferometers on difference. By adjusting Si-wire in asymmetric arms MZI, an ideal can be obtained, while modified interference...

The dual function of illumination and visible light communication is a promising solution for low-cost high-speed wireless access network. To realize high optical power large modulation bandwidth, the cascade GaN-based top-emitting blue micro-light-emitting diode array chips are proposed. electrical, optical, performances series or parallel with 1, 4, 10 pixels characterized discussed. With increasing number pixels, configuration gives high-voltage chip, while under same current density...

The dual-function of a wavelength beam splitter and power is desired in both classical optics quantum optics. We propose triple-band large-spatial-separation at visible wavelengths using phase-gradient metasurface the x - y -directions. Under -polarized normal incidence, blue light split -direction into two equal-intensity beams owing to resonance inside single meta-atom, green another size variation between adjacent meta-atoms, while red passes directly without splitting. meta-atoms was...

Three-dimensional backside mirrors patterned by microscale hemispheres were proposed to enhance the light extraction efficiency (LEE) of light-emitting diode (LED) chips. In a thorough investigation, various design parameters, including duty ratio, pattern materials, concave/convex style, aspect types mirrors, and chip configurations, studied using Monte Carlo ray tracing method. The square lattice with radius constants was designed. It is shown that close-packed hemisphere preferred....