Abstract: A light-emitting device includes a circuit carrier board having a short side and a long side, a plurality of light-emitting units on the circuit carrier board for emitting three or more color lights, and a light-transmitting glue layer on the circuit carrier board and covering the plurality of light-emitting units. The short side is shorter than the long side. The plurality of light-emitting units include a first light-emitting unit. The first light-emitting unit has a light exit surface, a first sidewall, and a second sidewall. The first sidewall faces the short side and has a first included angle with the light exit surface, and the second sidewall faces the long side and has a second included angle with the light exit surface. The first included angle is between 85 to 95 degrees, and the second included angle is less than 85 degrees or greater than 105 degrees.

Abstract: A display device includes a first light-emitting module and a second light-emitting module. Each light-emitting module has a substrate, a plurality of LED dies arranged on the substrate, a reflective layer on the substrate, and a light-transmissive layer. The light-transmissive layer covers the substrate, the plurality of LED dies, and the reflective layer. Both the light-transmissive layer of the first module and the light-transmissive layer of the second module have rough uppermost surfaces. The first light-emitting module has a first reflectivity, the second light-emitting module has a second reflectivity, and a standard deviation between the first reflectivity and the second reflectivity is not greater than 0.5.

Abstract: A system and method for balancing a battery pack is disclosed. The method includes the step of monitoring voltages for all batteries in the battery pack and if the voltages of any two batteries are out of balance, then, issuing a balancing command to charge the battery that is relatively lower in voltage between the two until the voltage of the battery attaining a preset voltage. The battery-pack balancing system includes a battery-monitoring unit and a battery-balancing unit. The battery-monitoring unit monitors the voltage of all the batteries in the battery pack and, when the voltages of any of the two batteries in the battery pack is out of balance, issues a balancing command to charge the battery that is relatively lower voltage in the battery pack.