Patent ID: 8425271

Claim:
A method of forming an LED lamp with a desired distribution of phosphor, the method comprising: selecting a desired position of phosphor particles with respect to an LED chip; selecting a particle size of a plurality of phosphor particles based on a viscosity of an uncured polymer resin in response to temperature changes and based on said desired position of the phosphor particles with respect to the LED chip; mixing a plurality of phosphor particles in the uncured polymer resin for which the viscosity can be controlled in response to temperature to form a substantially uniform suspension of the phosphor particles in the resin; placing the uncured resin into a defined position adjacent the LED chip; increasing the temperature of the resin in a first step to a temperature that correspondingly decreases the viscosity of the resin without immediately curing the resin; encouraging the phosphor particles to settle in the lowered-viscosity resin to the desired position with respect to the LED chip; and in response to the phosphor particles having settled at the desired position, thereafter increasing the temperature of the substantially uncured resin in a second step to a temperature higher than the first step and at which it will cure and solidify in about two hours or less.