Patent ID: 7912365

Claim:
A charged capacitor switching device for a photoflash, comprising: a flash control unit, comprising the photoflash and a driving unit, wherein the driving unit controls a flash duration of the photoflash; a capacitor charging/discharging unit coupled to the flash control unit, comprising a plurality of capacitors connected in parallel and switches respectively coupled thereto for controlling charge or discharge operations for each capacitor, wherein the capacitors determine a flash intensity of the photoflash; a charged capacitor switching unit coupled to the capacitor charging/discharging unit, determining whether each switch is opened or closed according to a compensation parameter and driving the photoflash to generate a corresponding flash illumination through at least two of the capacitors; and an illumination modulator coupled to the flash control unit and the charged capacitor switching unit, comparing an environmental illumination and a pre-flash illumination to generate a compared result, determining whether the compared result has reached a threshold, obtaining the compensation parameter according to the compared result when the compared result is below the threshold, and driving the flash control unit to generate the corresponding flash illumination according to the compensation parameter.