Patent ID: 8368099

Claim:
A light emitting device, comprising: a substrate, having a surface; at least one transparent tubular structure, formed on the surface of the substrate and including an inner tube wall and an outer tube wall, the inner tube wall being vertical to the surface, the outer tube wall and the surface forming an acute angle and having a space formed therebetween, wherein two ends of the at least one transparent tubular structure have respective openings, and the at least one transparent tubular structure is disposed on the surface of the substrate by one end; at least one light emitting chip, disposed on the surface of the substrate and surrounded by the at least one transparent tubular structure; and at least one fluorescent conversion layer, disposed in the at least one transparent tubular structure and covering the at least one light emitting chip, wherein the at least one transparent tubular structure limits a distribution scope of the fluorescent conversion layer, a ratio of a maximal vertical thickness and a maximal horizontal thickness of the at least one fluorescent conversion layer at the at least one light emitting chip is between 1.5 and 4 and a margin of error for color temperatures of emitted light is with in 300K; wherein the maximal vertical thickness is the maximal vertical distance from a top surface of the at least one light emitting chip to a top surface of the at least one fluorescent conversion layer, the maximal horizontal thickness is the maximal horizontal distance from an outer part of a side surface of the at least one light emitting chip to an outer side surface of the fluorescent conversion layer.