Bridgelux Incorporated

R Scott West

Tao Tong

Mike Kwon

Michael Solomensky

Babak Imangholi

Michael Neal Gershowitz

Vladimir Odnoblyudov

Wenhui Zhang

Yan Chai

Robert Tudhope

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.

Light emitting diode constructions and methods for making the same

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.

Packaging photon building blocks with top side connections and interconnect structure

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.

Packaging a substrate with an LED into an interconnect structure only through top side landing pads on the substrate

A light source includes LED dies that are flip-chip mounted on a flexible plastic substrate. The LED dies are attached to the substrate using an asymmetric conductor material with deformable conducting particles sandwiched between surface mount contacts on the LED dies and traces on the substrate. A diffusively reflective material containing light scattering particles is used instead of expensive reflective cups to reflect light upwards that is emitted sideways from the LED dies. The diffusively reflective material is dispensed over the top surface of the substrate and contacts the side surfaces of the dies. The light scattering particles are spheres of titanium dioxide suspended in silicone. The light source is manufactured in a reel-to-reel process in which the asymmetric conductor material and the diffusively reflective material are cured simultaneously. A silicone layer of molded lenses including phosphor particles is also added over the mounted LED dies in the reel-to-reel process.

LED-based light source utilizing asymmetric conductors

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.

LED lens design with more uniform color-over-angle emission

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.

LED array member and integrated control module assembly having active circuitry

A layer of Highly Reflective (HR) material is deposited by jetting microdots of the HR material in liquid form onto a substrate and then allowing the HR material to harden. In one example, the HR layer is the HR layer of a white LED assembly. The HR layer is jetted onto the substrate around LED dice of the assembly after die attach and wire bonding have been completed. The HR material can be made to flow laterally so that areas of the substrate under wire bonds are coated with HR material, so that HR material contacts side edges of the LED dice, and so that HR material contacts the inside side edge of a retaining ring. By jetting the HR material in this way, the amount of substrate that is not covered with HR material is reduced, thereby improving the light efficiency of the resulting LED assembly.

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Pleasanton, CA, United States of America

R Scott West