Using Ultraprecision Machining to Fabricate LED Packaging Exhibiting High Luminous Intensity

Abstract

In this study, a phosphor was coated on a microstructured film to achieve light control. This process resulted in a large-area phosphor film and enabled the microstructure to be packaged directly into the LED body. Thus, the LEDs retain their air and water barrier functions, control light, achieve higher forward luminous intensity, and have a wider scope of applications. Roll-to-roll processing was performed to mold a microstructure and phosphor on polyethylene terephthalate (PET) film by applying ultraviolet light. This approach expedited the preparation of a large-area phosphor film and enabled the precise control of the thickness and evenness of the phosphor layer, thus ensuring uniform light distribution and eliminating the yellow halo within the light body induced by the uneven thickness of the phosphor layer. The experimental results revealed that the luminous intensity of the LED to which the microstructured PET film was attached at 0° (center) increased by 11.88% relative to the luminous intensity of the LED without the film. Moreover, at 30° to −30°, the luminous intensity of the LED with the film improved by 10.36%. Therefore, the device retained its color uniformity and achieved higher forward luminous intensity.