Bridgelux Incorporated

Yan Chai

Calvin B Ward

R Scott West

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

A light having a plurality of LEDs and a switching substrate is disclosed. The switching substrate is coupled to LEDs and includes a plurality of switches that provide a plurality of configurations for the LEDs. Each configuration is characterized by a two-dimensional array of LEDs having a minimum bias potential and a maximum bias potential, the LED array generating light when a bias potential is provided between the power terminals that is greater than the minimum bias potential, at least two configurations being operable to provide light at bias potential within this range. The switching substrate is sub-dividable into a plurality of identical multi-LED light sources by dividing the switching substrate along predetermined lines. The array of LEDs can be organized as a nested array of LEDs. The switches can be implemented as passive switches that are set by removing portions of conductors or bridging gaps in conductors.

Reconfigurable multi-LED light source

A light source and method for making the same are disclosed. The light source includes a plurality of surface mount LEDs that are bonded to a mounting substrate by a layer of asymmetric conductor. Each LED has surface mount contacts on a first surface thereof and emits light from a second surface thereof that is opposite the first surface. The mounting substrate includes a top surface having a plurality of connection traces. Each connection trace includes an n-trace positioned to underlie a corresponding one of the n-contacts and a p-trace positioned to underlie a corresponding one of the p-contacts, the p-trace having an area greater than the p-contact. The layer of asymmetric conductor is sandwiched between the surface mount contacts and the connection traces, and can optionally extend into the spaces between the LEDs to provide a scattering medium for redirecting light leaving the sides of the LEDs.

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Fremont, CA, United States of America

Yan Chai