No abstract

We have developed an analytical model for the design and optimization of common-path interferometers (CPI's) based on spatial filtering. We describe the mathematical analysis in detail and show how its application to the optimization of a range of different CPI's results in the development of a graphical framework to characterize quantitatively CPI performance. A detailed analytical treatment of the effect of curvature in the synthetic reference wave is undertaken. We show that it is possible to improve the linearity and fringe accuracy of certain standard interferometers by a modification of the Fourier filter, and we propose and analyze a dual CPI system for the unambiguous mapping of phase to intensity over the complete input phase range.

We demonstrate the application of the generalized phase-contrast (GPC) method to the implementation of a multiple-beam optical tweezer system. Experimental results show the generation of four optical tweezers from a fixed phase mask in conjunction with a GPC system to trap and hold 1-microm-sized polystyrene beads in solution.

No abstract

We have implemented a phase-only optical encryption and decryption system with a readout based on the generalized phase-contrast method. The experimental system has been implemented with liquid-crystal spatial light modulators to generate binary phase-encrypted masks and a decrypting key. A phase-contrast filter is used to display the phase information.