PURPOSE: To integrally constitute a reflection part and circuit part to reduce the size by forming recessed part on the rear surface of a reflection plate by matching the shape of the reflection plate with the shape of illumination and arranging the circuit part therein.

CONSTITUTION: In the reflection plate 1 for illuminating the liquid crystal display device, two pieces of the peak-shaped ruggedness are formed and three pieces of cathode ray tubes 2 which are the illumination are arranged in the spacings thereof. The light beams emitted from the cold cathode ray tubes 2 are introduced toward the liquid crystal display device directly or after reflection by the reflection plate 1 on the illumination side surface. The shape of the reflection plate 1 is adjusted to be such a shape that the direct light and reflected light from three pieces of the cathode ray tubes 2 are uniformly introduced to the liquid crystal display device. The circuit parts 3 are arranged in the recessed parts formed on the rear surface of the reflection plate 1. Namely, the circuit parts 3 are arranged into the gaps generated on the rear surface of the reflection plate 1 by forming the shape of the reflection plate 1 constituting the illumination device to have the ruggedness meeting the shape of the illumination. Therefore, the size over the entire part is reduced.