LED module with hermetic seal of wavelength conversion material

A light emitting device comprising:

• a substrate having a first thermal conductivity comprising a cavity;
• a light emitting diode located in the cavity of the substrate;
• a wavelength conversion material surrounding the light emitting diode, the wavelength conversion material comprising phosphor quantum dots dispersed in a binder, having a second thermal conductivity substantially lower than the first thermal conductivity, and having a total volume substantially larger than a total volume of the light emitting diode;
• a transparent plate disposed on the substrate and having a third thermal conductivity greater than the second thermal conductivity;
• and
• a sealant forming a hermetic seal between the transparent plate and the substrate.

A light emitting device comprising:

• a substrate having a first thermal conductivity;
• a light emitting diode on the substrate;
• a wavelength conversion material surrounding the light emitting diode, the wavelength conversion material comprising phosphor powder or quantum dots dispersed in a binder, having a second thermal conductivity substantially lower than the first thermal conductivity, and having a total volume substantially larger than a total volume of the light emitting diode;
• a transparent plate disposed on the substrate and having a third thermal conductivity greater than the second thermal conductivity, the transparent plate comprising a cavity, the light emitting diode and wavelength conversion material located in the cavity;
• and
• a sealant forming a hermetic seal between the transparent plate and the substrate.