ILLUMINATING DEVICE

Light can be made visible in such a manner to move while avoiding an increase in size of an illuminating device. An illuminating device 1A, 1 B comprises an optical guiding body 10A to 10G configured to dispose linear optical guiding members 11, 12, 13, 14 side by side in the width direction of the optical guiding members, the linear optical guiding members 11, 12, 13, 14 guiding light incident from one end in the longitudinal direction to the other end side, optical sources 20A to 20D prepared respectively for the optical guiding members to emit light toward the corresponding optical guiding members, and a control unit 30 configured to control lighting-up/lighting-out of each of the optical sources. The optical guiding body 10A to 10G includes a first optical guiding member 11 and a second optical guiding member 12 adjacent thereto in the width direction, a luminance distribution of illuminating light in the longitudinal direction emitted from the first optical guiding member 11 becomes the darker according to being closer to the other end side from one end side, a luminance distribution of illuminating light in the longitudinal direction emitted from the second optical guiding member 12 becomes the brighter according to being closer to the other end side from one end side, and the control unit 30 lights up the optical source 20A of the first optical guiding member and the optical source 20B of the second optical guiding member alternately.