Light source apparatus for emitting light in accordance with adjusted driving condition and endoscope apparatus

A light source apparatus comprising:

• at least one light-emitter configured to emit light;
• a driving circuit configured to apply a driving waveform to the at least one light-emitter, wherein the driving waveform includes a cyclic pulse waveform;
• a temperature control circuit configured to:
• receive, as an input, a predetermined effective light power of the light emitted from the at least one light-emitter;
• and
• control the at least one light-emitter to be in a predetermined heat generation state by increasing or decreasing a heat generation amount of the at least one light-emitter without changing the predetermined effective light power of the light emitted from the at least one light-emitter by adjusting a driving condition of the at least one light-emitter;
• and
• an effective light power setting circuit configured to drive the driving circuit to allow the at least one light-emitter to emit light with the predetermined effective light power, in accordance with the driving condition adjusted by the temperature control circuit,
• wherein one of a peak current value of the cyclic pulse waveform and a duty cycle is set as the driving condition,
• wherein the effective light power setting circuit is configured to determine the other of the peak current value of the cyclic pulse waveform and the duty cycle, which has not been set as the driving condition, so that an effective light power of the light emitted by the at least one light-emitter becomes the predetermined effective light power, and
• wherein a cycle of the cyclic pulse waveform is a cycle where the at least one light-emitter is not thermally responsive.

An endoscope apparatus comprising:

• at least one light-emitter configured to emit light;
• a driving circuit configured to apply a driving waveform to the at least one light-emitter, wherein the driving waveform includes a cyclic pulse waveform;
• a temperature control circuit configured to:
• receive, as an input, a predetermined effective light power of the light emitted from the at least one light-emitter;
• and
• control the at least one light-emitter to be in a predetermined heat generation state by increasing or decreasing a heat generation amount of the at least one light-emitter without changing the predetermined effective light power of the light emitted from the at least one light-emitter by adjusting a driving condition of the at least one light-emitter;
• an effective light power setting circuit configured to drive the driving circuit to allow the at least one light-emitter to emit light with the predetermined effective light power, in accordance with the driving condition adjusted by the temperature control circuit,
• wherein one of a peak current value of the cyclic pulse waveform and a duty cycle is set as the driving condition, and
• wherein the effective light power setting circuit is configured to determine the other of the peak current value of the cyclic pulse waveform and the duty cycle, which has not been set as the driving condition, so that an effective light power of the light emitted by the at least one light-emitter becomes the predetermined effective light power;
• and
• an imaging apparatus,
• wherein a cycle of the cyclic pulse waveform is set to be a fraction of a natural number of an image frame cycle of the imaging apparatus.