Light emitting device, display apparatus with an array of light emitting devices, and display apparatus method of manufacture
A light emitting device and display apparatus using a plurality of light emitting devices can drastically reduce contrast loss due to light from an external source. The light emitting device has a light emitting chip(s) and a first layer covering the light emitting chip(s). A second layer includng a light scattering material is provided at least over the first layer, andthe surface of the second layer has a plurality of protrusions which follow the topology of the light scattering material. The display apparatus is formed by disposing these light emitting devices in an array on a substrate.
1. A method of manufacturing a display apparatus including a plurality of light emitting devices disposed on a substrate, the light emitting devices each having a light emitting chip and a first layer covering the light emitting chip, said method comprising:
disposing the light emitting devices on the substrate; and
forming a second layer including light scattering material at least over the upper surfaces of the first layer on an observer's side of the substrate such that the average thickness of the second layer is smaller than the average diameter of the light scattering material.
2. A method of manufacturing a display apparatus as recited in claim 1 , further comprising simultaneously forming the second layer including the light scattering material at least over the upper surface of the substrate on the observer's side.
3. A method of manufacturing a display apparatus as recited in claim 2 , wherein the second layer is formed over the upper surfaces of the first layer and the substrate by spray application.
4. A method of manufacturing a display apparatus as recited in claim 3 , wherein:
each light emitting device comprises
a light emitting chips,
a first layer covering the light emitting chips, and
a second layer including light scattering material provided at least over the first layer, and
a surface of the second layer has a plurality of protrusions following the topology of the light scattering material;
each light emitting device has a package with a cavity and the light emitting chip is disposed on a surface at the base of the cavity;
the first layer is positioned at least within the cavity;
the upper surface of the first layer is a concave surface;
the second layer is positioned at least over the concave surface of the first layer; and
the light scattering material has particulate form.