US Patent No. 10,062,819

SHALLOW REFLECTOR CUP FOR PHOSPHOR-CONVERTED LED FILLED WITH ENCAPSULANT


Patent No. 10,062,819
Issue Date August 28, 2018
Title Shallow Reflector Cup For Phosphor-converted Led Filled With Encapsulant
Inventorship Mark Melvin Butterworth, San Jose, CA (US)
Assignee Lumileds LLC, San Jose, CA (US)

Claim of US Patent No. 10,062,819

1. A light emitting device comprising:a reflective cup comprising a specular material and having reflective surfaces that slope monotonically upward from a central portion of the cup at an angle between 28 degrees and 38 degrees;
a light emitting diode (LED) die mounted in the central portion of the cup and emitting a first light of a first wavelength;
a phosphor positioned over the LED die; and
a clear encapsulant filling the cup to cover at least a top of the phosphor coating, the encapsulant having a flat outer surface substantially parallel to a top surface of the LED die,
wherein the phosphor absorbs a portion of the first light and emits a second light of a second wavelength,
wherein the encapsulant has an air-encapsulant interface arranged such that at least a portion of the first light unabsorbed by the phosphor coating and at least a portion of the second light intercept the air-encapsulant interface at an angle less than a critical angle and are totally internally reflected (TIR) as a first reflected light in a direction toward at least one of the reflective surfaces,
wherein the reflective surfaces reflect the first reflected light as a second reflected light in a direction that passes through the air-encapsulant interface.