Patent ID: 8038325

Claim:
An illumination device, comprising: a light-emitting tube having a pair of electrodes; a main reflecting mirror that reflects light from the light-emitting tube toward an illumination region; an auxiliary reflecting mirror that reflects the light from the light-emitting tube toward the light-emitting tube, the auxiliary reflecting mirror having an inner surface and an outer surface, the inner surface being inclined at an angle with respect to an ideal inner surface, the ideal inner surface being defined as a surface that reflects the light from a center of an arc image generated between the pair of electrodes so that the light reflected by the ideal inner surface passes through the center of the arc image, the auxiliary reflecting mirror having a mounting support portion, the auxiliary reflecting mirror being fixed to the light-emitting tube in a condition that a focal point of a reflecting film is made to coincide with the arc image; and the reflecting film provided on the outer surface, the reflecting film on the outer surface reflecting light from the center so that the light reflected by the reflecting film passes toward the center within 3 mm.