Lumileds LLC

Aimi Abass

Antonio Lopez-Julia

Venkata Ananth Tamma

Toni Lopez

Philipp-Immanuel Schneider

Isaac Wildeson

Thomas Diederich

Niels Jeroen Van Der Veen

Rémi Guillebot

A semiconductor diode structure has one or more light-emitting active layers and a redirection layer on the back surface that includes one or more of an array of nano-antennae, a partial photonic bandgap structure, a photonic crystal, or an array of meta-atoms or meta-molecules, and exhibits non-specular internal reflective redirection of output light incident thereon within the diode structure. One or both of the front or back surfaces exhibit position-dependent redirection, reflection, or transmission of the output light, including one or both of (i) position-dependent internal reflective redirection of output light incident on the back-surface or (ii) position-dependent internal reflective redirection, or position-dependent transmissive redirection, of output light incident on a front-surface layer or coating. Position dependence of luminance of output light exiting the diode structure can differ from position dependence of emission from the active layer. With uniform emission across the active layer, output light can exhibit position-dependent luminance.

Light-emitting device with internal non-specular light redirection and position-dependent reflection, transmission, or redirection

A light-emitting device includes a semiconductor diode structure with one or more light-emitting active layers, an anti-reflection coating on its front surface, and a redirection layer on its back surface. Active-layer output light propagates within the diode structure. The anti-reflection coating on the front surface increases transmission of active-layer output light incident below the critical angle Θc. Active-layer output light incident on the redirection layer at an incidence angle greater than Θc is redirected to propagate toward the front surface at an incidence angle that is less than Θc. Device output light is transmitted by the front surface to propagate in an ambient medium, and includes first and second portions of the active-layer output light incident on the front surface at an incidence angle less than Θc, the first portion without redirection by the redirection layer and the second portion with redirection by the redirection layer.

Light-emitting device with internal non-specular light redirection and anti-reflective exit surface

Optical filters are used to compensate for changes in LED and pcLED performance resulting from technological advances in device design or manufacturing, with for example the filtered optical output from later generation devices matching or substantially matching the optical performance of earlier generation legacy devices. This can allow the advanced generation devices to be substituted in applications previously supported by the legacy devices, even if the optical performance of the unfiltered advanced generation devices does not satisfy the optical performance specifications required by the application. Somewhat paradoxically, the advantages of using the filters in combination with the advanced generation devices may arise from the filters making the optical performance of the devices worse according to one or more figures of merit.

Optical filters compensating for changes in performance of next generation LEDs compared to legacy devices

An LED structure includes an epi layer grown on a substrate and a plurality of dielectric nanoantennas positioned within the epi layer. The dielectric antennas can be periodically arranged to reduce reabsorption of light and redirect oblique incident light to improve overall light coupling efficiency. Each of the dielectric nanoantennas can have a top, a bottom, a height less than 1000 nm and greater than 200 nm and a diameter less than 2000 nm and greater than 300 nm.

Nanocone arrays for enhancing light outcoupling and package efficiency

A semiconductor light-emitting device includes a junction or active layer between doped semiconductor layers coextensive over a contiguous device area, corresponding sets of electrical contacts connected to the semiconductor layers, and multiple nanostructured optical elements at a surface of one semiconductor layer opposite the other semiconductor layer. Composite electrical contacts of one set include a conductive layer, a transparent dielectric layer between the conductive and semiconductor layers, and vias through the dielectric layer connecting the conductive and semiconductor layers. The nanostructured elements redirect light, propagating laterally in optical modes supported by the semiconductor layers, to exit the device. The composite electrical contacts can be independent and define independently addressable pixel areas of the device. The nanostructured elements and thin semiconductor layers can yield high contrast between adjacent pixel areas without trenches between them. A drive circuit can provide drive current that differs among pixel areas.

Light-emitting device with nano-structured light extraction layer

A light-emitting array includes a semiconductor LED structure, multiple transparent dielectric bodies, a set of multiple, independent first electrical contacts, and a set of second electrical contacts. The LED structure extends contiguously over the array. The second electrical contacts are in electrical contact with the second semiconductor layer. Each dielectric body protrudes away from the first semiconductor layer and has on its surface an electrically conductive layer in electrical contact with the first semiconductor layer, forming a portion of a corresponding one of the first electrical contacts. Each dielectric body and corresponding first electrical contact define a corresponding discrete, circumscribed pixel region within the contiguous area of the array, each pixel region separate from the others. Some light emitted in the pixel region propagates into the dielectric body, undergoes internal reflection(s) within the dielectric body, and propagates out of the array through the dielectric body and diode structure.

Light-emitting array with dielectric light collection structures

A light-emitting device includes a semiconductor diode structure with one or more light-emitting active layers, an anti-reflection coating on its front surface, and a redirection layer on its back surface. Active-layer output light propagates within the diode structure. The anti-reflection coating on the front surface increases transmission of active-layer output light incident below the critical angle &#x398;. Active-layer output light incident on the redirection layer at an incidence angle greater than &#x398;is redirected to propagate toward the front surface at an incidence angle that is less than &#x398;. Device output light is transmitted by the front surface to propagate in an ambient medium, and includes first and second portions of the active-layer output light incident on the front surface at an incidence angle less than &#x398;, the first portion without redirection by the redirection layer and the second portion with redirection by the redirection layer.

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Aachen, Germany

Aimi Abass