[en] Using plasma theory, the interaction is studied between high frequency and magnetohydrodynamic (MHD) waves, from which a set of coupling equations resulted. On the basis of this formalism, the modulation instabilities of an electromagnetic soliton in a current sheet are examined, and it is shown that there is a resistive instability at the onset of the magnetic field reconnection. This mechanism could be used to explain the onset of solar flares and prominences. To improve the resolution of vector magnetic fields at the sun's surface, state-of-the-art optics is examined to improve the design and fabrication of a new spaceborne solar vector magnetograph as part of the SAMEX (Solar Active Measurements Experiment) program