The variation in phase of the resultant field being non-linearly related to the changes in phase difference between the interfering complex fields, the ensuing enhancement in sensitivity for phase detection in optical metrology is achieved.

Asymmetry in the object is used as a tool to eliminate the twin-image problem. By carrying out the simulations as well as the experiment, the validity of the proposed scheme has been proven. The proposed method only requires calculating the object support information. For most of the objects, the support information can be retrieved from the object autocorrelation itself without requiring additional measurements.

A novel method is proposed and demonstrated experimentally to retrieve the 2D as well as the 3D complex object from its autocorrelation. The method utilizes edge point referencing, therefore, does not require any separate reference to record the hologram. Being common-path, it is robust to external vibrations. The employment of the amplitude shifting in the proposed setup as opposed to phase shifting also avoids using expensive components required to perform phase shifting operation.

This work improves upon the best known theoretical limits of phase sensitivity as obtained through intensity measurements in a Mach-Zehnder interferometer.

This work resolves the separability/entanglement issue exactly for a class of bipartite states.