A light-generating device includes a driving substrate and a plurality of light source arrays. The driving substrate has a rectangular planar shape. The plurality of light source arrays is formed on the driving substrate. The light source arrays include at least one light emitting diode to generate light in response to power being applied through the substrate, and the light source arrays are spaced apart from each other. Thus, heat generated from the light-generating device is rapidly dissipated from the light-generating device, improving brightness of the light, brightness uniformity of the light and color reproducibility of the light.