HIGH BRIGHTNESS ILLUMINATION DEVICE USING DOUBLE-SIDED EXCITATION OF WAVELENGTH CONVERSION MATERIALS

摘要

An illumination devices using excitation light and a wavelength conversion material to generated converted light for illumination, where the wavelength conversion material is excited by multiple excitation lights from both sides to achieve increased brightness. The excitation lights incident on the two sides of the wavelength conversion material may have the same color or different colors. Light separation structures are provided on both sides of the wavelength conversion material to separate the excitation light and the converted light. Light separation may be based on color difference or etendue difference of the excitation light and converted light. In one particular example, wavelength conversion material is formed on a surface of an LED which acts as the first excitation light source, and a second excitation light is delivered through a light separation structure onto the other side of the wavelength conversion material.