Abstract: Light-emitting diode (LED) devices and, more particularly, frequency-controlled LED devices and related methods are disclosed. LED devices include frequency-controlled circuitry that controls changes to electrical activation of one or more LED chips based on changes to input signal frequencies. Input signals are provided in a pulsed manner and the frequency-controlled circuitry controls how long one or more LED chips are electrically activated during each pulse. In certain aspects, the frequency-controlled circuitry delays current flow through one or more LED chips according to a time delay. By adjusting the frequency of the input signal, the amount of time the one or more LED chips are electrically activated during each pulse is adjustable. Corresponding LED packages include LED chips and integrated frequency-controlled circuitry so that separate control for LED chips is provided without requiring separate input signals.

Abstract: Solid-state lighting devices including light-emitting diodes (LEDs) and more particularly LED packages for environmental indication are disclosed. LED packages include one or more LED chips and reactive materials that preferentially react with environmental ingress. After sufficient reactant exposure, the reactive materials may degrade and exhibit reduced electrical conductivity. Reactive material arrangements relative to electrical connections are provided so that the one or more LED chips either turn on, turn off, or lose brightness to provide visual indication of environmental reactants. Reactive materials may form electrical shorting paths that bypass one or more LED chips until sufficient reactant exposure when the shorting paths fail and the one or more LED chips are electrically activated.

Abstract: Light-emitting diode (LED) packages, and more particularly arrangements of multiple LED chips in LED packages are disclosed. Arrangements include different types, different dimensions, and/or different orientations of LED chips within LED packages and corresponding electrical connections. Further arrangements include individual cover structures having different dimensions for various LED chips to accommodate thickness variations of LED chips and/or thickness variations attributed to different elements of individual cover structures. Different cover structure elements may include lumiphoric materials, antireflective layers, filter layers, and polarization layers. By accounting for dimensional variations between LED chips and/or between cover structures within multiple-chip LED packages, aggregate light-emitting surfaces may be provided with improved emission uniformity.

Abstract: Solid-state lighting devices including light-emitting diodes (LEDs) and more particularly cover structure arrangements for packaged LED devices are disclosed. Cover structures include light-absorbing layers configured to absorb certain wavelengths of light while permitting other wavelengths to pass therethrough. Light-absorbing layers may include pigment materials of colors that absorb intended wavelengths of light. In certain aspects, an LED package may include an LED chip configured to emit light of a first peak wavelength and a cover structure that includes a light-absorbing layer with a pigment of a color that absorbs the first peak wavelength. Such an arrangement may be useful for embodiments that also include a lumiphoric material that converts a portion of the first peak wavelength to light of a second peak wavelength.

Abstract: Light-emitting diode (LED) devices and more particularly lens arrays in LED packages are disclosed. Lens arrays include one or more lens shapes positioned to receive light from LED chip arrays. Individual lenses of lens arrays may be separately formed in LED packages on various surfaces, such as on top surfaces of encapsulant layers that cover LED chip arrays. Shapes of individual lenses may be tailored to provide various emission patterns. Exemplary lens arrays in LED packages include all lenses of a same shape or variably shaped lenses within a same lens array. Differently shaped lenses may be arranged over LED chips of a same serially connected string so that emission patterns and/or colors may be dynamically adjusted during operation.

Abstract: Solid-state lighting devices including light-emitting diode (LED) chips and more particularly interconnect structures for improved LED chip performance are disclosed. Interconnect structures are disclosed within LED chips that are structured to increase perimeter contact areas within localized LED chip areas without substantial increases to overall areas occupied by the interconnect structures. By increasing contact perimeters of interconnects within a certain area, increased current injection efficiency may be provided. Interconnect structures for increased current injection are disclosed for both n-type layers and p-type layers. Interconnect structures may include patterned dielectric materials within interconnect openings and corresponding interconnects that are formed around the patterned dielectric materials. Additional interconnect structures include nested patterns and extensions that provide enhanced adhesion along LED chip perimeters.

Abstract: Light-emitting diode (LED) packages and more particularly error detection in LED packages is disclosed. LED packages are arranged for cascade communication as part of a larger LED display. A separate active electrical element is integrated with each LED package for facilitating active matrix addressing from a data stream, checking input error detection codes, and generating new output error detection codes to the data stream. Each electrical element within each LED package is separately capable of changing one or more portions of received data in the data stream, transmitting the changed data to the next downstream LED package, and generating output error detection codes based on the changed data. When the active electrical element identifies corrupted data based on input error detection codes, the generated output error detection codes may be intentionally corrupted so downstream LED packages will also identify the respective data as being corrupted.

Abstract: The present disclosure relates to techniques for providing a liquid metal alloy in a light-emitting diode device that can both heal cracks formed in solder joints on the light-emitting diode (LED) device as well as improve thermal energy dissipation from the LED chips to improve the performance, reduce wear, and prolong the life of the LED chips. In an embodiment, a light-emitting diode device can include a liquid metal alloy containing gallium next to a solder joint, and when one or more cracks form, the liquid metal alloy can enter the cracks and solidify, healing the cracks. The liquid metal alloy can also be placed adjacent to, and in contact with the LED chip to transfer energy away from the LED chips.

Abstract: Light-emitting diode (LED) packages and more particularly LED packages with directional emission intensity and color uniformity are disclosed. LED packages include one or more LED chips on a submount with arrangements of light-altering materials and lumiphoric material layers that provide directional light emissions with improved color over angle uniformity. Light-altering materials are provided that cover sidewalls of LED chips while lumiphoric material layers cover LED chips and light-altering materials. Such LED packages may avoid the need to include encapsulation materials and/or lenses that would otherwise cover the lumiphoric material layers. As such, exterior light-exiting faces of LED packages are formed by surfaces of lumiphoric material layers.

Abstract: Synchronization for light emitting diode (LED) pixels in an LED display is provided so that one or more actions of all LED pixels are able to be initiated at the same time, or within a millisecond. LED displays and corresponding systems may include a controller that is configured for sending communication signals to one or more strings of LED pixels. Active electrical elements within each LED pixel may be configured to receive the communication signals, generate corresponding synchronization signals, and respond in a manner that is coordinated with all other LED pixels in a particular LED display. Failure mitigation of LED pixel failures within an LED string is provided where the controller is configured with bidirectional communication ports for communication with the LED string. In a failure mitigation process, the bidirectional communication ports may switch directions to provide communication signals to both sides of an LED string.

Abstract: Solid-state lighting devices including light-emitting diodes (LEDs) and more particularly contact structures in LED chips for reducing voiding of bonding metals are disclosed. LED chips include active LED structures on carrier submounts and contact structures arranged to receive external electrical connections adjacent the active LED structures. Exemplary contact structures include contacts electrically coupled to active LED structures and dielectric structures beneath the contacts. Dielectric structures are arranged beneath portions of the contacts while still allowing electrical connections therethrough. Such dielectric structures may be provided as regions of dielectric material with spacings that control topography of underlying bonding metals to reduce voiding.

Abstract: Light-emitting diode (LED) chips and, more particularly, structures of LED chips with electrically insulating substrates and related methods are disclosed. LED chips include at least one opening that extends through a substrate to provide an electrical pathway to an active LED structure. Another electrical connection may be provided on the active LED structure in a position that forms a vertical contact arrangement. The at least one opening may extend through the substrate and into a portion of the active LED structure to provide increased surface area for the electrical connection. Additional LED chip structures include another opening on the active LED structure that is registered with the opening in the substrate, and electrical connections to a same layer of the active LED structure may be provided within each opening. Related methods include laser drilling the at least one opening in the substrate.

Abstract: A light emitting device comprises a light emitting diode (LED) chip having a dominant wavelength in a range from about 390 nm to about 560 nm, an encapsulant in optical communication with the LED chip, and coated phosphor particles dispersed in the encapsulant. Each of the coated phosphor particles comprises (a) a luminescent particle having a first refractive index at the dominant wavelength, and (b) an optical coating on the luminescent particle, where the optical coating has a second refractive index at the dominant wavelength. The second refractive index is between the first refractive index and a refractive index of the encapsulant at the dominant wavelength.

Abstract: Light-emitting diode (LED) packages and, more particularly, LED packages with varying current pulse width modulation (PWM) signals and related methods are disclosed. Varying current PWM is provided by having multiple current sources at different current levels for each LED chip in an LED package. An output PWM signal for each LED chip is routed to selectively turn on and off different combinations of current sources to provide varying current levels associated with varying brightness levels for each LED chip. By providing multiple current sources for each LED chip, the dynamic range of current levels and corresponding brightness levels may be increased for a same PWM clock frequency.

Abstract: Light-emitting diode (LED) packages and more particularly LED packages with lead frame structures for flip-chip mounting of LED chips are disclosed. Lead frame structures include multiple leads with arrangements for LED chips to be flip-chip mounted across neighboring pairs of leads. Arrangements of stress relief features and anchoring features relative to mounting locations are provided in lead frame structures to enhance mechanical integrity of flip-chip bonds during thermal cycling. LED packages may further include housings that are formed about the lead frame structures. Housings may include a recess with recess floor arrangements for positioning of LED chips.

Abstract: Methods and related systems for transfer of semiconductor die and more particularly for mass transfer of semiconductor die, such as light-emitting diodes, using transfer elements are disclosed. Certain aspects relate to methods of continuous mass transfer using roller feed loops. Two carrier bars move in opposite directions, one with die and one with a substrate. The die stick to a roller and transfer from a die carrier to the substrate on a substrate carrier. In certain aspects, transfer elements may include rollers, flexible rollers, or expandable rollers. Transfer elements may further include alignment features, such as alignment pockets, that provide enhanced die alignment. In certain aspects, transfer elements may include one or more planar surfaces that rotate positions relative to the die carrier and the substrate carrier.