<p>A light source device which can also advantageously control the growth of the projection using the DMD type is achieved in a light source device which has an ultrahigh pressure discharge lamp) in which the silica glass discharge vessel is filled with greater than or equal to 0.15 mg/mm 3 mercury and bromine; a feed device; an oval reflector; and a color wheel by the electrode on the side of the opening of the oval reflector of the discharge lamp having an increased diameter, and the relation 0.06 < W/I 2 < 0.96 between the volume W (mm 3 ) of the tip area with increased diameter and the current value I being satisfied.</p>