To assemble a photometry circuit without impairing the utility of a stroboscopic device.

A charging circuit for performing the high-voltage charging for a main capacitor 28 before the start of strobe-photographing and a strobe light control circuit are arranged on respective substrates. Main circuit parts constituting the constant light emission stroboscopic device are mounted on the rear side of the main substrate 23 with the charging circuit mounted, and a printed wire pattern is formed on the front side of the main substrate 23. Chip parts constituting the strobe light control circuit are mounted on the front surface of a sub-substrate 24. The sub-substrate 24 is attached to the main substrate 23 so that it may be overlaid on the pattern surface side of the main substrate 23. In this case, the sub-substrate 24 is connected to the charging circuit by applying solder to the terminal of the main capacitor 28 and the terminal of a synchronous switch 27.