부산대학교 도서관

A total internal reflection (TIR) shell capable of generating illuminating light with a wide-angle distribution from light-emitting diodes (LEDs) is proposed. The TIR shell can be used to create an LED light bulb with enclosed heat dissipaters to release the heat generated by the LEDs. The TIR shell has light-scattering areas on its inner surface and a mirror-polished free-form outer surface that can guide all rays emitted from the LEDs to the scattering areas by the TIR. The rays diffused by the light-scattering areas are emitted from the TIR shell in a wide-angle light distribution. A prototype of the LED light bulb with a metal shell for heat dissipation inside the TIR shell shows favorable features such as a half-intensity angle of 330°, lighting efficiency of 81%, and glare-free lighting emitted from the entire surface area of the TIR shell.