To provide an illuminator that can improve an appearance shape without increasing the number of parts.

The illuminator comprises a body case, a front cover 9 mounted to approximately wrap a front aperture of the body case, a lamp 2 received and arranged in the front aperture of the body case and a reflecting plate 14 received and arranged in the front aperture of the body case to reflect light from the lamp 2 to the front direction, etc. In the body case, two screws 38 are inserted into screw apertures mounted on a left body 8 and then screwed into nuts 40 mounted in a right body 7 as the upper part of the knob 17, two screws 37 are inserted into screw apertures mounted on the left body 8 and then screwed into the nuts 39 mounted in the right body 7 in the vicinity of the upper part and the lower part of the rear portion 33 of the body case, and one screw 36 is inserted into a screw aperture mounted in the left body 8 and then screwed into a nut 62 mounted on the right body 7 in the vicinity of the lower part of the front aperture of the body case.