A transparent coating is provided on a surface of a light-emitting diode. The coating includes a fluorescent substance. The wavelength of an emitted light peculiar to the light-emitting diode is changed by the fluorescent substance contained in the coating to change the luminescent color. The fluorescent substance is an yttrium aluminate fluophor or a perylene fluophor. This makes it easier to change the color of light emitted from the light-emitting diode to a desired color.