To eliminate a strobe switch from a film unit with lens provided with a protecting cover.

The film unit with lens is provided with the protecting cover which protects an imaging lens from scratches and stains. The operation of opening and closing the protecting cover is linked to the operation of turning a charging switch 22 on and off. During the protecting cover closed, the charging switch 22 is at the off position. When the protecting cover opened, the charging switch 22 is turned on. When the charging switch 22 is turned on, a main capacitor 23 and a trigger capacitor 27 start to be charged. During the protection cover opened, a gate voltage of a thyristor 29 varies due to a variation of resistance of a CdS 6 in response to subject brightness. If the subject brightness is high, the thyristor 29 is cut off and the trigger capacitor 27 is not discharged even if a synchronized switch 21 is closed. If the subject brightness is low, the thyristor 29 is conducting and the trigger capacitor 27 can be discharged.