Abstract: The present invention discloses a modular charging device and a cooling structure thereof. The modular charging device comprises a housing, at least one battery package socket located on the housing, and a PCB located in the housing, the at least one battery package socket being located at one or two sides of the PCB, at least one battery package being electrically connectable into the at least one battery package socket in a plug-in manner, and the battery package socket comprising a battery package insertion slot extending inwards from the housing to the PCB. A cooling structure for a modular charging device comprises an air inlet disposed at one end of a housing, an air outlet at another end, and a pathway between a first PCB and a second PCB, the fan causing an airflow to flow through the pathway.

Abstract: A mobile phone comprises an outer shell having patterns thereon, a sub-screen and a backlight unit disposed between the outer shell and the sub-screen to illuminate the patterns on the outer shell and display images on the sub-screen. The backlight unit includes a light source to emit light, a light guide disposed underneath the outer shell to direct light emitted from the light source and an optical film formed between the light guide and the sub-screen. The light source is disposed on one end of a stack including the light guide and the optical film. The optical film has a reflection rate and a transmission rate.