Optical Characterization of Three-dimensional Light-emitting LED

The luminescence performance characterized by luminous flux,color temperature,chromaticity coordinate of three-dimensional light emitting diodes( LEDs) has been investigated by using different phosphor coating methods. The LED die was directly coating with mixed phosphors and silicone which have the maximum total luminous flux. However,this encapsulation incurs luminous uneven problem of front and back which limit three-dimensional luminescence application. Therefore,this work attempts to use the silicon and spreading powder to change the light path on the basis of less loss of luminous flux. Experimental results indicate that the brightness uniformity can be improved when increasing silicon layer between LED die and phosphor,while spreading powder layer would induce significant light attenuation. Moreover,the three packing have similar light angle. Therefore,silicon layer provides an alternative packing solution for three-dimensional LED light application.