Sharp Kabushiki Kaisha Corporation

Tim Michael Smeeton

Edward Andrew Boardman

Enrico Angioni

James Andrew Robert Palles-Dimmock

David James Montgomery

Michael James Brownlow

Tong Lu

Stewart Edward Hooper

Valerie Berryman-Bousquet

Karl Peter Welna

Nick Clark

Jun Mori

Iain Hamilton

Jonathan Heffernan

Peter Neil Taylor

Katherine Louise Smith

Samir Rihani

Robin Mark Cole

Mathieu Xavier Sénès

Naoki Ueda

Christopher James Brown

Nathan James Smith

Mayuko Sakamoto

Noriaki Fujii

Sarah Anne Mitchell

Jacob Thomas Barrett

Jing Li

Isabel Arranz De La Calle

A quantum dot LED display apparatus includes a substrate having a plurality of banks deposited thereon. A plurality of red emitting LED sub-pixels, green emitting LED sub-pixels, and blue emitting LED sub-pixels are individually disposed between the banks. Each of the red emitting LED sub-pixels, green emitting LED sub-pixels, and blue emitting LED sub-pixels has an emissive layer, wherein each of the emissive layers comprises quantum dots, an organic matrix, and a photoinitiator. A first concentration of the photoinitiator in the blue emitting LED sub-pixels is lower than a second concentration of the photoinitiator in the red emitting LED sub-pixels, and lower than a third concentration of the photoinitiator in the green emitting LED sub-pixels.

UV patternable matrix containing blue light emitting quantum dots

A light emitting device includes a first electrode, a second electrode, and an emissive layer between the first and second electrodes. The emissive layer comprises quantum dots that are capable of producing circularly polarized luminescence. The quantum dots are chiral structured perovskite quantum dots, each comprising a core having a chiral crystal structure.

Chiral perovskite quantum dots for circularly polarized QLEDs and method of making the same

A shock-absorbing display panel apparatus for folding flat screen displays, the shock-absorbing apparatus includes a planar display layer comprising a viewing surface and an opposing non-viewing surface, the display layer further comprising at least one folding region and at least one non-folding region for folding along at least one axis of rotation; a shock absorber in co-planar peripheral contour with the display layer, the shock absorber having at least one first discontinuity sub-dividing the shock absorber into physically separate regions; an adhesive layer disposed between the shock absorber and the non-viewing surface; and wherein the adhesive layer has at least one second discontinuity between the shock absorber and the display panel in the at least one folding region of the display layer.

Foldable display panel with shock absorber

A light-emitting device is configured to emit light in improved accordance with the Rec. 2020 specification. The light emitting device includes a substrate; a first electrode disposed on the substrate between an outer surface of the light emitting device and the substrate; a second electrode disposed between the first electrode and the outer surface; a first emissive layer in electrical contact with the first electrode and the second electrode, wherein the first emissive layer includes quantum dots that emit light when electrically excited, and wherein the first emissive layer is associated with a first peak wavelength, &#x3bb;; and a second emissive layer disposed between the first emissive layer and a viewing side of the light emitting device, wherein the second emissive layer is a photoluminescent layer that includes quantum dots that emit light when optically excited, and the second emissive layer is associated with a second peak wavelength, &#x3bb;, different from the first peak wavelength. The second emissive layer operates to convert a portion of light emitted by the first emissive layer from the first peak wavelength to the second peak wavelength, such that the resultant overall emission is in accordance with the Rec. 2020 specification.

Cadmium-free quantum dot LED with improved emission color

A light-emitting layer structure that maximizes constructive interference for light emission by varying a phase shift introduced by reflective electrodes. The light-emitting layer structure includes a first and second optical cavity including a first and second reflective electrode; a first and second partially transparent electrode; and a first and second emissive layer (EML) disposed between the first and second reflective electrodes and the first and second partially transparent electrodes, wherein the first EML emits light having a first wavelength; wherein the first reflective electrode introduces a first phase shift, depending on the first wavelength, on reflection of light emitted by the first EML; and wherein the second EML emits light having a second wavelength and the second reflective electrode introduces a second phase shift, depending on the second wavelength, on reflection of light emitted by the second EML, and the first phase shift is different from the second phase shift.

High-efficiency QLED structures

A light-emitting device includes an anode, a cathode, and a crosslinked emissive layer disposed between the anode and the cathode in which quantum dots are dispersed. The crosslinked layer includes a crosslinked material and quantum dots dispersed in the crosslinked mater, the quantum dots having ligands respectively bonded to the quantum dots. The quantum dots are distributed unevenly within the crosslinked material. The ligands have a concentration relative to the weight of the quantum dots of 10 to 45 wt %. A method of forming a crosslinked emissive layer of a light-emitting device in which quantum dots are dispersed includes the steps of depositing a mixture on a deposition surface and subjecting at least a portion of the mixture to an activation stimulus to crosslink the cross-linkable material.

Light-emitting device with crosslinked emissive layer including quantum dots with ligands bonded thereto

A light emitting structure comprises a bank surrounding a sub-pixel stack on a substrate, a first filler material in an interior space above the sub-pixel stack, and a second filler material over the first filler material. The sub-pixel stack emits a first emission peak along an on-axis direction substantially normal to a top surface of the sub-pixel stack and through an interface between the first and second filler materials. The sub-pixel stack emits a second emission peak along an off-axis direction that is totally internally reflected by the interface before reaching a sloped sidewall of the bank and is then emitted along the on-axis direction. An emissive area of the sub-pixel stack is configured such that the second emission peak is reflected by the interface not more than once before reaching the sloped sidewall.

Multiple QD-LED sub-pixels for high on-axis brightness and low colour shift

A display system includes a display panel comprising a plurality of pixel circuits, and a measurement and data processing unit that is external to the display panel. Each pixel circuit includes a light-emitting device having a first terminal connected to a first voltage supply and a second terminal opposite from the first terminal; a first transistor connected between a data voltage supply line from the measurement and data processing unit and the second terminal of the light emitting device; and a second transistor connected between the second terminal of the light-emitting device and a sample line to the measurement and data processing unit. The measurement and data processing unit samples a measured voltage at the second terminal of the light-emitting device through the sample line and outputs a data voltage to the light-emitting device based on the measured voltage to compensate variations in properties of the light-emitting device.

Method of operating a pixel circuit using direct charging and that performs light-emitting device compensation

A light emitting structure comprises a substrate, a sub-pixel stack over a surface of the substrate, and a bank surrounding the sub-pixel stack on the substrate. The light emitting structure also comprises a first filler material in the interior space, and a second filler material over the first filler material. The sub-pixel stack emits a first emission peak along an on-axis direction substantially normal to a top surface of the stack and emits a second emission peak along an off-axis direction at an angle to the on-axis direction. The first emission peak is emitted through an interface between the first filler material and the second filler material substantially without total internal reflection. The second emission peak is totally internally reflected by the interface before reaching a sloped sidewall of the bank and is emitted along the on-axis direction.

High on-axis brightness and low color shift QD-LED pixel

A light-emitting device has improved impact resistance over conventional configurations. Such a light-emitting device includes a display panel layer, a housing layer, an impact absorbing layer adjacent the housing layer, a metal layer that is disposed between the impact absorbing layer and the display panel layer and that is deformable during an impact on the light-emitting device, and a compliant layer that is disposed between the metal layer and the display panel layer that enables a shape of the display panel layer to be maintained when the metal layer is deformed. Due to a compliance or low stiffness of the compliant layer, a permanent deformation of the metal layer due to an impact or device shape change is not discernibly transferred into the shape of the display panel layer, and the shape of the display panel layer is essentially maintained so that an impact or shape change does not adversely affect display performance.

Impact absorbing element for display device

A light-emitting device incorporates an electrode that includes conductive nanoparticles to increase emission performance. A light-emitting device includes a substrate; a first electrode disposed on the substrate between a viewing side of the light-emitting device and the substrate; a second electrode disposed between the first electrode and the viewing side of the light-emitting device, wherein the second electrode includes a layer of nanoparticles that are electrically conductive; and an emissive layer comprising quantum nanoparticles in electrical contact with the first electrode and the second electrode, wherein the first emissive layer includes a material that emits light when electrically excited. Multiple light-emitting devices may constitute sub-pixels that are combined into a pixel, such as for a display device, wherein each sub-pixel emits light of a different color. Thicknesses of the charge transport layers are the same for the sub-pixels, and/or emissive layer portions of the different sub-pixels have different thicknesses.

Light-emitting device with transparent nanoparticle electrode

A cover window for a display device comprising a substrate, a joining layer and an outer cover, wherein the cover window has at least one folding region and at least one non-folding region. The substrate in the folding region has openings filled with at least a first filler material and a second filler material, wherein a stiffness of the first filler material is less than a stiffness of the second filler material, and the stiffness of the second filler material is less than a stiffness of the substrate.

Flexible window for foldable display

A light-emitting device has enhanced light output by employing a reflective optical cavity along the bank structure to improve light extraction. The light-emitting device includes a bank structure; an emissive cavity disposed within the bank structure; a filler material layer disposed within the bank structure and on a light-emitting side of the emissive cavity; and a reflective optical cavity disposed along an inner surface of the bank structure facing the filler material layer. The reflective optical cavity is configured to out-couple light that is internally reflected by an emitting side surface of the filler material layer and is incident on the reflective optical cavity. The reflective optical cavity incudes a first conductive layer and a second conductive layer that are separated by a non-conductive dielectric layer. The first conductive layer is disposed against the inner surface of the bank structure, and the second conductive layer is disposed against the filler material layer opposite from the inner surface of the bank structure. The emissive cavity includes an emissive layer disposed between a first electrode layer and a second electrode layer, and the first conductive layer may be configured as an extension of the first electrode layer and the second conductive layer may be configured as an extension of the second electrode layer.

QLED/OLED pixel having reflective cavity electrode configuration

A method is disclosed for forming an emissive layer of a light-emitting device. One or more layers of the light-emitting device are formed. A solution including quantum dots having ligands at the outer surface thereof is contacted with the uppermost layer of the light-emitting device. A portion of the solution is subjected to external activation stimuli to form a crosslinked layer on the uppermost formed layer of the light-emitting device, the crosslinked layer including the ligands at the outer surface of the quantum dots in a crosslinked state. The solution is washed away, and the crosslinked layer is contacted with ligand exchange solution including compact ligands to perform a ligand exchange. Also disclosed is a light-emitting device including an anode, cathode, and emissive layer disposed therebetween, the emissive layer including quantum dots and compact ligands at the outer surface thereof.

Photo-patterned emissive layer containing passivated quantum dots, arrangement of light-emitting devices including same, and method of making same

A pixel circuit compensates the threshold voltage variations of the drive transistor with an ultra-short one horizontal (1H) time, with additionally removing the possible memory effects associated with the light-emitting device and the drive transistor from the previous frame. An ultra-short 1H time (&#x3c;2 &#x3bc;s) is achieved via separation of threshold compensation of the drive transistor and data programming phases. The pixel circuit has a two-capacitor configuration, whereby a first capacitor is used for drive transistor threshold compensation, and a second capacitor is used to store the data voltage during a data pre-loading phase. Two transistors are employed to electrically connect the gate and source of the drive transistor to a common initialization voltage during an initialization phase to reset circuit voltages for the current frame. In this manner, no current flows through the drive transistor to the light-emitting device during the initialization phase when the light-emitting device does not emit light, which saves power. An array of individual pixel circuits is controlled using a global compensation scheme in which global control signals are applied to the individual pixel circuits of the pixel array.

Growing community of inventors

Oxford, United Kingdom

Tim Michael Smeeton