Reversal construction of polarization-controlled focusing field with multiple focal spots

We propose an approach to control the polarization and intensity of the focusing field with multiple focal spots in a high-numericalaperture imaging system. This focused field is explained as the reversal radiation of the dipole array with presupposed oscillating direction in the focal volume. By engineering the structure of the electric dipole array and reversing the radiation from this dipole array, the local manipulation of intensity and polarization in the focal region is achieved, and the required field at the pupil plane is derived. A focusing field with six vectorial focal spots is created as an example to verify this method. This multifocal field will meet potential application in polarization-dependent optical microscope and optical trapping for multiple particles. (C) 2013 Society of PhotoOptical Instrumentation Engineers (SPIE)