Light emitting sealed body, light emitting unit, and light source device

A light emitting sealed body comprising:

• a housing which stores a discharge gas and is provided with a first opening to which first light is incident and a second opening from which second light is emitted, wherein the first light is from a laser light source configured for maintaining plasma generated in the discharge gas and the second light is light from the plasma;
• a first window portion which includes a first window member allowing the first light to be transmitted therethrough and hermetically seals the first opening;
• and a second window portion which includes a second window member allowing the second light to be transmitted therethrough and hermetically seals the second opening, wherein each of the first window member and the second window member is hermetically fixed to the housing by a joining material, and wherein a protection layer which covers the joining material is provided at at least one of a first joining position between the first window member and the housing and a second joining position between the second window member and the housing.