Apart from ordinary solar cell applications, we have attempted different approaches of device applications. We have fabricated two types of organic photovoltaic (OPV) cells with DBP/C₆₀ heterojunction and measured their spectral photo responses when they are in planar heterojunction (PHJ) and bulk heterojunction (BHJ) type. According to our results, blue light exhibits spectrally outstanding PV effects and the PHJ device showed higher open circuit voltage (V_OC) along with ten times faster switching photo-dynamics than those performances of BHJ device, although the mixture type BHJ diode appears much superior to PHJ diode in all spectral ranges of quantum efficiency. Large junction area of mixture type OPV diode is certainly an advantage in photocurrent generation and quantum efficiency, but is regarded as a disadvantage for dynamic PV switching and V_OC value because complex route and high density interface traps are unavoidable in BHJ structure. Selecting the blue light illumination on DBP/C₆₀ PHJ diode, we achieve most efficient PV switching and PV gating in logic and amplifier circuits, respectively. Conclusively, bilayer OPV device has its own advantage over mixture type device in dynamic PV switching, and it promises future electronics by exploiting the dynamic harvest of light energy.