Light-emitting device, flash device, imaging system, and imaging method

A light-emitting device comprising:

• a light-emitting component configured to emit light upon receiving a supply of electric power;
• a capacitor configured to supply the electric power to the light-emitting component;
• a switching element configured to control the supply of the electric power by turning ON and OFF;
• and
• an inductor connected between the light-emitting component and the capacitor,
• the light-emitting device having:
• a first emission mode in which the switching element is turned ON to cause the light-emitting component to emit light over a first period, and thereafter the switching element is turned OFF;
• and
• a second emission mode in which the ON and OFF of the switching element are repeated to cause the light-emitting component to perform continuous light emission over a second period longer than the first period,
• wherein the inductor includes a core coil having a magnetic core,
• wherein the core coil has a first inductance value during a peak current in the first emission mode, and has a second inductance value during an average current in the second emission mode, and
• wherein the second inductance value is greater than the first inductance value.