摘要:
Light emitting diode (LED) constructions comprise an LED having a pair of electrical contacts along a bottom surface. A lens is disposed over the LED and covers a portion of the LED bottom surface. A pair of electrical terminals is connected with respective LED contacts, are sized larger than the contacts, and connect with the lens material along the LED bottom surface. A wavelength converting material may be interposed between the LED and the lens. LED constructions may comprise a number of LEDs, where the light emitted by each LED differs from one another by about 2.5 nm or less. LED constructions are made by attaching 2 or more LEDs to a common wafer by adhesive layer, forming a lens on a wafer level over each LED to provide a rigid structure, removing the common wafer, forming the electrical contacts on a wafer level, and then separating the LEDs.
摘要:
Standardized photon building blocks are used to make both discrete light emitters as well as array products. Each photon building block has one or more LED chips mounted on a substrate. No electrical conductors pass between the top and bottom surfaces of the substrate. The photon building blocks are supported by an interconnect structure that is attached to a heat sink. Landing pads on the top surface of the substrate of each photon building block are attached to contact pads disposed on the underside of a lip of the interconnect structure. In a solder reflow process, the photon building blocks self-align within the interconnect structure. Conductors on the interconnect structure are electrically coupled to the LED dice in the photon building blocks through the contact pads and landing pads. The bottom surface of the interconnect structure is coplanar with the bottom surfaces of the substrates of the photon building blocks.
摘要:
Light emitting diode (LED) constructions comprise an LED having a pair of electrical contacts along a bottom surface. A lens is disposed over the LED and covers a portion of the LED bottom surface. A pair of electrical terminals is connected with respective LED contacts, are sized larger than the contacts, and connect with the lens material along the LED bottom surface. A wavelength converting material may be interposed between the LED and the lens. LED constructions may comprise a number of LEDs, where the light emitted by each LED differs from one another by about 2.5 nm or less. LED constructions are made by attaching 2 or more LEDs to a common wafer by adhesive layer, forming a lens on a wafer level over each LED to provide a rigid structure, removing the common wafer, forming the electrical contacts on a wafer level, and then separating the LEDs.
摘要:
A light-emitting diode (LED) device includes first and second LED dies with the same structure and that are both encapsulated by the same silicone layer. The first LED is supplied with sufficient drive current to illuminate the LED. Control circuitry supplies the second LED with a constant current, determines the voltage across the second LED, and calculates the temperature of the second LED based on the voltage across the second LED. The constant current has a maximum magnitude that never exceeds the maximum magnitude of the drive current. The LED device is able to calculate the temperature of a diode with a gallium-nitride layer (GaN or GaInN) that is receiving a large drive current and emitting blue light by determining the voltage across an adjacent similar diode with a gallium-nitride layer through which a small constant current is flowing. Preferably, the band gap of the LEDs exceeds two electron volts.
摘要:
An LAM/ICM assembly comprises an integrated control module (ICM) and an LED array member (LAM). The ICM includes interconnect through which power from outside the assembly is received. In a first novel aspect, active circuitry is embedded in the ICM. In one example, the circuitry monitors LED operation, controls and supplies power to the LEDs, and communicates information into and out of the assembly. In a second novel aspect, a lighting system comprises an AC-to-DC converter and a LAM/ICM assembly. The AC-to-DC converter outputs a substantially constant current or voltage. The magnitude of the current or voltage is adjusted by a signal output from the LAM/ICM. In a third novel aspect, the ICM includes a switching DC-to-DC converter. An AC-to-DC power supply supplies a roughly regulated supply voltage. The switching converter within the LAM/ICM receives the roughly regulated voltage and supplies a regulated LED drive current to its LEDs.
摘要:
Using compression molding to form lenses over LED arrays on a metal core printed circuit board leaves a flash layer of silicone covering the contact pads that are later required to connect the arrays to power. A method for removing the flash layer involves blasting particles of sodium bicarbonate at the flash layer. A nozzle is positioned within thirty millimeters of the top surface of the flash layer. The stream of air that exits from the nozzle is directed towards the top surface at an angle between five and thirty degrees away from normal to the top surface. The particles of sodium bicarbonate are added to the stream of air and then collide into the top surface of the silicone flash layer until the flash layer laterally above the contact pads is removed. The edge of silicone around the cleaned contact pad thereafter contains a trace amount of sodium bicarbonate.
摘要:
Standardized photon building blocks are used to make both discrete light emitters as well as array products. Each photon building block has one or more LED chips mounted on a substrate. No electrical conductors pass between the top and bottom surfaces of the substrate. The photon building blocks are supported by an interconnect structure that is attached to a heat sink. Landing pads on the top surface of the substrate of each photon building block are attached to contact pads disposed on the underside of a lip of the interconnect structure. In a solder reflow process, the photon building blocks self-align within the interconnect structure. Conductors on the interconnect structure are electrically coupled to the LED dice in the photon building blocks through the contact pads and landing pads. The bottom surface of the interconnect structure is coplanar with the bottom surfaces of the substrates of the photon building blocks.
摘要:
Standardized photon building blocks are packaged in molded interconnect structures to form a variety of LED array products. No electrical conductors pass between the top and bottom surfaces of the substrate upon which LED dies are mounted. Microdots of highly reflective material are jetted onto the top surface. Landing pads on the top surface of the substrate are attached to contact pads disposed on the underside of a lip of the interconnect structure. In a solder reflow process, the photon building blocks self-align within the interconnect structure. Conductors in the interconnect structure are electrically coupled to the LED dies in the photon building blocks through the contact pads and landing pads. Compression molding is used to form lenses over the LED dies and leaves a flash layer of silicone covering the landing pads. The flash layer laterally above the landing pads is removed by blasting particles at the flash layer.
摘要:
An LED device with improved angular color performance has a silicone lens shaped as a portion of a sphere. The lens is molded over an array of LED dies disposed on the upper surface of a substrate. Phosphor particles are disbursed throughout the material used to mold the lens. The distance between farthest-apart edges of the LED dies is more than half of the length that the lens extends over the surface of the substrate. The distance from the top of the lens dome to the surface of the substrate is between 57% and 73% of the radius of the sphere. Shaping the lens as the top two thirds of a hemisphere reduces the non-uniformity in the emitted color such that neither of the CIE color coordinates x or y of the color changes more than 0.004 over all emission angles relative to the surface of the substrate.
摘要:
Standardized photon building blocks are packaged in molded interconnect structures to form a variety of LED array products. No electrical conductors pass between the top and bottom surfaces of the substrate upon which LED dies are mounted. Microdots of highly reflective material are jetted onto the top surface. Landing pads on the top surface of the substrate are attached to contact pads disposed on the underside of a lip of the interconnect structure. In a solder reflow process, the photon building blocks self-align within the interconnect structure. Conductors in the interconnect structure are electrically coupled to the LED dies in the photon building blocks through the contact pads and landing pads. Compression molding is used to form lenses over the LED dies and leaves a flash layer of silicone covering the landing pads. The flash layer laterally above the landing pads is removed by blasting particles at the flash layer.