Display backlight with closely spaced light-emitting diode packages

摘要

An electronic device may be provided with a display having backlight structures that include a light guide plate formed from a clear polymer film. The polymer film may have an edge into which light is emitted from an adjacent array of light-emitting diodes. The light emitting diodes may each include a semiconductor device that emits light. The semiconductor device in each diode may be mounted on lead frame structures and wirebonded to the lead frame structures with first and second wire bonds. To improve backlight homogeneity and thereby reduce the mixing distance for light in the light guide plate, the diodes may be spaced closely together using diode packages having end faces that are free of lead frame structures. Exposed lead frame structures for soldering the light-emitting diodes to a substrate may be formed under the light-emitting diodes and on rear surfaces of the light-emitting diodes.

主权项

1. Display backlight structures, comprising:
a light guide plate having an edge; a dielectric substrate layer having solder pads; and light-emitting diodes arranged in a row along the edge that emit light into the edge, wherein each light-emitting diode includes a package having opposing front and rear surfaces, wherein each light-emitting diode includes first and second lead frame structures and a semiconductor device mounted to and wirebonded to one of the lead frame structures, wherein the package comprises a plastic body that covers at least some of the first and second lead frame structures, wherein the front surface comprises a window through which the light is emitted, wherein the plastic body further comprises a lower surface on which portions of the first and second lead frame structures are formed, wherein the plastic body further comprises opposing end faces that are free of lead frame structures, wherein the light-emitting diodes are soldered to the dielectric substrate layer by soldering the portions of the first and second lead frame structures on the lower surface to the solder pads with solder, and wherein the lead frame structures include lead frame terminals on the rear surface.