Distributed bragg reflector for reflecting light of multiple wavelengths from an LED
First Claim
1. A Light Emitting Diode (LED) device comprising:
- a substrate; and
a reflector structure disposed below the substrate, the reflector structure comprising;
a low-index total internal reflection layer (TIR) disposed below the substrate;
a Distributed Bragg Reflector (DBR) disposed below the TIR; and
a reflective metal layer disposed below the DBR,wherein the DBR comprises a first plurality of periods and a second plurality of periods, wherein each of the first plurality of periods includes a first layer of a high index dielectric material with a first thickness and a second layer of silicon dioxide with a second thickness, and wherein each of the second plurality of periods includes a first layer of the high index dielectric material with a third thickness and a second layer of silicon dioxide with a fourth thickness,wherein the TIR is a single layer of silicon dioxide that is thicker than any silicon dioxide layer of the DBR.
5 Assignments
0 Petitions
Accused Products
Abstract
A blue LED device has a transparent substrate and a reflector structure disposed on the backside of the substrate. The reflector structure includes a Distributed Bragg Reflector (DBR) structure having layers configured to reflect yellow light as well as blue light. In one example, the DBR structure includes a first portion where the thicknesses of the layers are larger, and also includes a second portion where the thicknesses of the layers are smaller. In addition to having a reflectance of more than 97.5 percent for light of a wavelength in a 440 nm-470 nm range, the overall reflector structure has a reflectance of more than 90 percent for light of a wavelength in a 500 nm-700 nm range.
73 Citations
14 Claims
-
1. A Light Emitting Diode (LED) device comprising:
-
a substrate; and a reflector structure disposed below the substrate, the reflector structure comprising; a low-index total internal reflection layer (TIR) disposed below the substrate; a Distributed Bragg Reflector (DBR) disposed below the TIR; and a reflective metal layer disposed below the DBR, wherein the DBR comprises a first plurality of periods and a second plurality of periods, wherein each of the first plurality of periods includes a first layer of a high index dielectric material with a first thickness and a second layer of silicon dioxide with a second thickness, and wherein each of the second plurality of periods includes a first layer of the high index dielectric material with a third thickness and a second layer of silicon dioxide with a fourth thickness, wherein the TIR is a single layer of silicon dioxide that is thicker than any silicon dioxide layer of the DBR. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
Specification