LED WITH REMOTE PHOSPHOR LAYER AND REFLECTIVE SUBMOUNT

摘要

A light emitting device comprises a flip-chip light emitting diode (LED) die mounted on a submount (12). The top surface of the submount has a reflective layer. Over the LED die is molded a hemispherical first transparent layer (36). A low index of refraction layer (68) is then provided over the first transparent layer to provide TIR of phosphor light. A hemispherical phosphor layer (70) is then provided over the low index layer. A lens (72) is then molded over the phosphor layer. The reflection achieved by the reflective submount layer, combined with the TIR at the interface of the high index phosphor layer and the underlying low index layer, greatly improves the efficiency of the lamp. Other material may be used. The low index layer may be an air gap ( 46) or a molded layer (68). Instead of a low index layer, a distributed Bragg reflector (76) may be sputtered over the first transparent layer.