1948results about How to "Improve quantum efficiency" patented technology

An oxynitride phosphor consisting of a crystal containing at least one or more of Group II elements selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn, at least one or more of Group IV elements selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf, and a rare earth element being an activator R, thereby providing a phosphor which is excited by an excitation light source at an ultraviolet to visible light region and which has a blue green to yellow luminescence color that is wavelength converted.

An electronic device comprising a population of quantum dots embedded in a host matrix and a primary light source which causes the dots to emit secondary light of a selected color, and a method of making such a device. The size distribution of the quantum dots is chosen to allow light of a particular color to be emitted therefrom. The light emitted from the device may be of either a pure (monochromatic) color, or a mixed (polychromatic) color, and may consist solely of light emitted from the dots themselves, or of a mixture of light emitted from the dots and light emitted from the primary source. The dots desirably are composed of an undoped semiconductor such as CdSe, and may optionally be overcoated to increase photoluminescence.

Provided is a chemical wet preparation method for Group 12-16 compound semiconductor nanocrystals. The method includes mixing one or more Group 12 metals or Group 12 precursors with a dispersing agent and a solvent followed by heating to obtain a Group 12 metal precursor solution; dissolving one or more Group 16 elements or Group 16 precursors in a coordinating solvent to obtain a Group 16 element precursor solution; and mixing the Group 12 metal precursors solution and the Group 16 element precursors solution to form a mixture, and then reacting the mixture to grow the semiconductor nanocrystals. The Group 12-16 compound semiconductor nanocrystals are stable and have high quantum efficiency and uniform sizes and shapes.

A light-emitting device comprises a light-emitting member, which comprises two electrodes and an organic electroluminescent material disposed between the electrodes, and at least one organic photoluminescent ("PL") material. The light-emitting member emits light having a first spectrum in response to a voltage applied across the two electrodes. The organic PL material absorbs a portion of the light emitted by the light-emitting member and emits light having second spectrum different than the first spectrum. The light-emitting device can include an inorganic PL material that absorbs another portion of the light emitted from the light-emitting member and emits light having a third spectrum different than both the first and the second spectra.

Methods are disclosed for producing highly doped semiconductor materials. Using the invention, one can achieve doping densities that exceed traditional, established carrier saturation limits without deleterious side effects. Additionally, highly doped semiconductor materials are disclosed, as well as improved electronic and optoelectronic devices/components using said materials. The innovative materials and processes enabled by the invention yield significant performance improvements and/or cost reductions for a wide variety of semiconductor-based microelectronic and optoelectronic devices/systems. Materials are grown in an anion-rich environment, which, in the preferred embodiment, are produced by moderate substrate temperatures during growth in an oxygen-poor environment. The materials exhibit fewer non-radiative recombination centers at higher doping concentrations than prior art materials, and the highly doped state of matter can exhibit a minority carrier lifetime dominated by radiative recombination at higher doping levels and higher majority carrier concentrations than achieved in prior art materials. Important applications enabled by these novel materials include high performance electronic or optoelectronic devices, which can be smaller and faster, yet still capture or emit light efficiently, and high performance electronics, such as transistors, which can be smaller and faster, yet cooler.

A method of fabricating an apparatus for an enhanced imaging sensor consisting of pixellated micro columnar scintillation film material for x-ray imaging comprising a scintillation substrate and a micro columnar scintillation film material in contact with the scintillation substrate. The micro columnar scintillation film material is formed from a doped scintillator material. According to the invention, the micro columnar scintillation film material is subdivided into arrays of optically independent pixels having interpixel gaps between the optically independent pixels. These optically independent pixels channel detectable light to a detector element thereby reducing optical crosstalk between the pixels providing for an X-ray converter capable of increasing efficiency without the associated loss of spatial resolution. The interpixel gaps are further filled with a dielectric and or reflective material to substantially reduce optical crosstalk and enhance light collection efficiency.

A system for oxygen, hydrogen and carbon mass regeneration and recycling for breathing, and fuel/energy generation purposes, especially for fuel cells and rocket motors, by combination and integration of a photoelectrolytically powered electrochemical and gas handling system with one or more fuel cells.

The invention discloses a composite dielectric grating MOSFET based dual-transistor light-sensitive detector. Each of the unit detectors comprises two transistors, wherein the two transistors comprise a photoreceptive transistor and a reading transistor which are used for implementing the photoreceptive function and the reading function respectively, both of the two transistors are formed above a composite dielectric grating MOSFET substrate P-type semiconductor material (1) and are separated through shallow trench isolation (STI), a bottom layer of an insulating dielectric material, a top layer of the insulating dielectric material and a control grid (2) are arranged above the substrate P-type semiconductor material respectively, a photoelectron storage layer (4) is arranged between the two layers of insulating dielectric materials, a source/drain electrode is arranged on the reading transistor to read signals, and the two transistors are connected through the photoelectron storage layer, so that the reading transistor can read photoelectrons which are stored by the photoreceptive transistor in the photoelectron storage layer through sensitization.

The invention discloses a full-automatic scanning system and a method for a microscopic section. The system comprises an object stage, a lighting device, an object lens, a Z-axis controller, a scanning camera and a computing device, the scanning camera is provided with a rolling shutter exposure mode and a banded array or banded subarray reading mode, the scanning camera performs a continuous digital imaging scanning for a banded partial area of a section sample which moves at a constant speed along a shutter rolling direction of the scanning camera, under the rolling shutter exposure mode, the scanning camera can perform a parallel exposure for next frame of image before the exposure of a former frame of image is finished, and the computing device can splice each frame of image which is subjected to continuous exposure to form a complete digital section. By means of the technical scheme, the uniform motion speed of the section sample can be improved, simultaneously the motion blurring caused by sample motion during exposure of the scanning camera can be reduced, the image acquisition speed is improved, and the image acquired by the scanning camera is clear and stable.

A nanoparticle fluorescence (or upconversion) sensor comprises an electromagnetic source, a sample and a detector. The electromagnetic source emits an excitation. The sample is positioned within the excitation. At least a portion of the sample is associated with a sensory material. The sensory material receives at least a portion of the excitation emitted by the electromagnetic source. The sensory material has a plurality of luminescent nanoparticles luminescing upon receipt of the excitation with luminance emitted by the luminescent nanoparticles changing based on at least one of temperature and pressure. The detector receives at least a portion of the luminance emitted by the luminescent nanoparticles and outputs a luminance signal indicative of such luminance. The luminescence signal is correlated into a signal indicative of the atmosphere adjacent to the sensory material.

The present invention relates to a preparation method of carbon quantum dots with adjustable fluorescence colors, and belongs to the technical field of nanometer materials. According to method, citric acid or a citrate is adopted as a carbon source, a nitrogen-containing compound is adopted as a nitridation agent, hydrogen peroxide is adopted as an oxidant, a hydrothermal synthesis method is adopted to obtain an aqueous solution of carbon quantum dots emitting blue or green fluorescence under ultraviolet light excitation, reaction conditions are easily controlled, and the method is suitable for scale production. The prepared carbon quantum dots have advantages of adjustable fluorescence color, high yield, high quantum efficiency, good result reproducibility and the like, wherein the product can be directly used for tumor cell labeling and live cell imaging labeling. According to the present invention, only the one reactant is required, the raw materials are easily-available and non-toxic, the production process does not require special protection, the reaction condition is easily controlled, and the obtained carbon quantum dots have advantages of high yield, high quantum efficiency, good result reproducibility and the like; and the method has characteristics of high yield, simple preparation process, low cost, easy scale production and the like.

Embodiments of the invention provide an imager pixel comprising a reflective layer formed over a substrate. There is a semiconductor layer over the reflective layer. A photo-conversion device is formed at a surface of the semiconductor layer. The reflective layer serves to reflect incident light not initially absorbed into the photo-conversion device, back to the photo-conversion device.

The invention relates to a preparation method of multicolor fluorescence fluorescent graphene quantum dots. According to the invention, pyrene with a low price is adopted as a precursor; oxygen functionalization is carried out on the surface of pyrene grains under low temperature; and low-temperature hydrothermal dehydrogenation, growth, and in-situ surface functionalization are carried out under the effect of a catalyst hydrazine and ammonia water. With the method provided by the invention, synthesized quantum dots can be stably dispersed in water. The quantum dots are brown under low concentration, and are approximately black under high concentration (the higher the concentration, the deeper the color). Light emitting color or wavelength is adjustable (blue to yellow, 450-535nm). The quantum dots provided by the invention show attractive application prospects in high-tech fields such as environmental protection, bio-nano technology, new energy, nano-device, and the like. The synthesizing method is simple and environment-friendly, and energy consumption is low. The method is suitable for industrial scale-up.

The invention provides a process for the production of a (particulate) luminescent material comprising particles, especially substantially spherical particles, having a porous inorganic material core with pores, especially macro pores, which are at least partly filled with a polymeric material with luminescent quantum dots embedded therein, wherein the process comprises (i) impregnating the particles of a particulate porous inorganic material with pores with a first liquid (“ink”) comprising the luminescent quantum dots and a curable or polymerizable precursor of the polymeric material, to provide pores that are at least partly filled with said luminescent quantum dots and curable or polymerizable precursor; and (ii) curing or polymerizing the curable or polymerizable precursor within pores of the porous material, as well as a product obtainable thereby.

An integrated application specific integrated circuit having a detection layer, a time delayed integration capability, data acquisition electronics, and a readout function is provided for detecting breast cancer in women. The detection layer receives x-ray radiation and converts the received energy to electron pairs, one of which is received by pixels. The time delay integration is on the chip and a part of the readout architecture. The detector may be a hybrid silicon detector (SiPD), a CdZnTe detector, or a GaAs detector.