Light source device, dielectric barrier discharge lamp lighting circuit, dielectric barrier discharge lamp lighting method

A lighting circuit for lighting a dielectric barrier discharge lamp, comprising:

• a direct-current power source,
• a transformer having a primary winding connected to the direct-current power source and a secondary winding connected to the dielectric barrier discharge lamp,
• a closed circuit in which the direct-current power source, the primary winding, and a switching element including a parasitic diode are serially connected, and
• a controller to perform ON/OFF control of the switching element, wherein
• the lighting circuit does not have a plurality of the transformers, and
• the controller executes:
• a first step to shift the switching element from an ON state to an OFF state and
• a second step to shift the switching element from the OFF state to the ON state after a lapse of a predetermined OFF holding time from when a regenerative current flowing through the primary winding reaches a zero value after the first step.

A dielectric barrier discharge lamp lighting method using a lighting circuit, the lighting circuit comprising:

• a direct-current power source,
• a transformer having a primary winding connected to the direct-current power source and a secondary winding connected to the dielectric barrier discharge lamp, and
• a closed circuit in which the direct-current power source, the primary winding, and a switching element including a parasitic diode are serially connected,
• the lighting circuit does not have a plurality of the transformers, and
• the method comprising:
• a first step to shift the switching element from an ON state to an OFF state and
• a second step to shift the switching element from the OFF state to the ON state after a lapse of a predetermined OFF holding time from when a regenerative current flowing through the primary winding reaches a zero value after the first step.