Ultraviolet light emitting device that can suppress time-dependent decrease in emission intensity during continuous operation

An ultraviolet light emitting device comprising:

• a first substrate having a main surface;
• a second substrate facing the main surface of the first substrate;
• a gas in a space between the first substrate and the second substrate;
• electrodes directly or indirectly on the main surface of the first substrate;
• a dielectric layer that is located directly or indirectly on the main surface of the first substrate and covers the electrodes;
• and
• a first light-emitting layer that is located directly or indirectly on the dielectric layer and emits ultraviolet light in the gas due to electrical discharge between the electrodes, wherein
• the first light-emitting layer has an uneven surface facing the second substrate due to being thicker in first regions on the dielectric layer than in second regions different from the first regions, the second regions including at least part of regions directly above the electrodes.