Wavelength conversion member, light source device, and method for manufacturing wavelength conversion member

A wavelength conversion member comprising:

• a ceramic fluorescent body for converting a wavelength of incident light;
• a heat radiation member for radiating heat of the ceramic fluorescent body to an outside atmosphere;
• and
• a solder layer for joining together the ceramic fluorescent body and the heat radiation member,
• wherein the solder layer includes a joining portion disposed between the ceramic fluorescent body and the heat radiation member and a protruding portion protruding outward from an outer circumferential portion of the ceramic fluorescent body, and
• a void fraction of the joining portion is lower than a void fraction of the protruding portion.

A wavelength conversion member comprising:

• a ceramic fluorescent body for converting a wavelength of incident light;
• a heat radiation member for radiating heat of the ceramic fluorescent body to an outside atmosphere;
• and
• a solder layer for joining together the ceramic fluorescent body and the heat radiation member,
• wherein the solder layer includes a joining portion disposed between the ceramic fluorescent body and the heat radiation member and a protruding portion protruding outward from an outer circumferential portion of the ceramic fluorescent body, and
• in the joining portion, a void fraction of a central portion through which a center axis of the wavelength conversion member extends is lower than a void fraction of a remaining portion of the joining portion remaining after exclusion of the central portion.