In a liquid crystal display device having a direct-lighting backlight using LEDs as a light source, the number of LEDs is reduced without causing unevenness in brightness. An LED is disposed under a cylindrical lens to be closer to one end of the lens than a middle part of the lens. Light emitted from the LED is outputted, as diffused light, upward from an end diffusion surface of the lens. A portion of the top surface of the lens makes up a total reflection surface to reflect light emitted from the LED and thereby cause the reflected light to head for the other end of the lens. Diffusion surfaces formed on the top surface and the bottom surface of the lens radiate diffused light upward of the lens, causing uniform light to be radiated from the whole top surface of the lens.