<;P>;PROBLEM TO BE SOLVED: To provide a light emitting diode (LED) illuminator enabling energy saving. <;P>;SOLUTION: The LED illuminator 1 includes a device body 2, a single LED light source 3 attached to the device body 2 as an illumination light source, and a dispersion plate 4 disposed on the output side of the LED light source 3 to disperse the light from the LED light source 3 and to have a reduced difference in illumination intensity between illumination intensity just beneath the LED light source 3 and that of the outermost shell of the LED light source 3 of 20% or less. The LED light source 3 is controlled to be repeatedly lighted on or off via pulse current. The lighting frequency of the pulse current is 56 kHz, and the duty cycle ratio of the pulse current between on and off periods is set up to 80%. <;P>;COPYRIGHT: (C)2009,JPO&INPIT