US 8,772,814 B2 · Phosphor layer containing transparent particles over blue LED

Abstract

LED dies are suspended in an ink and printed on a first support substrate to form a light emitting layer having a light emitting surface emitting primary light, such as blue light. A mixture of a transparent binder, phosphor powder, and transparent glass beads is formed as an ink and printed over the light emitting surface. The mixture forms a wavelength conversion layer when cured. The beads are preferably sized so that the tops of the beads protrude completely through the conversion layer. Some of the primary light passes through the beads with virtually no attenuation or backscattering, and some of the primary light is converted by the phosphor to secondary light. The combination of the secondary light and the primary light passing though the beads may form white light. The overall color is highly controllable by controlling the percentage weight of the beads.

Claims15

Dependent claims

A light emitting structure comprising:

a primary light source generating primary light;
a first mixture comprising wavelength conversion particles, transparent particles, and a binder, wherein the wavelength conversion particles and the transparent particles are substantially uniformly distributed in the binder, the first mixture overlying the primary light source, wherein the binder forms a layer having a thickness less than a diameter of the transparent particles in the first mixture,
wherein the transparent particles completely protrude through the binder along the layer,
wherein a first portion of the primary light passes through the transparent particles, and a second portion of the primary light is converted by the wavelength conversion particles to secondary light, and
wherein a combination of the secondary light and the primary light passing though the transparent particles contributes to an overall color emission.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application

13/906,751Filed 31 May 2013 · us provisional application

Priority

26 Oct 2012

Published

US 2014/0117387 A11 May 2014

Granted

8 Jul 2014

Term ends

Not estimatedThe source records don’t support an estimate.

Classification17 codes

F21K 9/64
Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction: using wavelength…
C09K 11/025
Use of particular materials as binders, particle coatings or suspension media therefor: non-luminescent particle coatings or suspension media
C09K 11/08
Luminescent materials, e.g. electroluminescent or chemiluminescent: containing inorganic luminescent materials
H10H 20/8511
Wavelength conversion means: characterised by their material, e.g. binder

Phosphor layer containing transparent particles over blue LED

Life of this patent

Phosphor layer containing transparent particles over blue LED

Life of this patent

Abstract

Claims15