The ability to control electrical resistance is important in many situations. How to realize a remarkable resistance change in a particular structure is at heart of many resistance effects. In this talk we report a novel approach to the control of resistance in a metal-oxide-semiconductor (MOS) structure by use of a laser via a phenomenon we call the bipolar-resistance effect (BRE). The most significant features of this BRE are an excellent spatial sensitivity and a large change ratio in resistance as a laser moves along the surface of a given MOS structure. In addition, this MOS structure also presents a very strong lateral photovoltaic effect (LPE), manifesting some natural superiorities to the semiconductor type LPE. We believe these effects may offer promising opportunities for the scalable implementation of many versatile photoelectric devices.