Enhancing phase measurement by factor of two in the stokes correlation

Phase loss is a typical problem in the optical domain and optical detectors measure only the amplitude distribution of the signal without a phase. However, phase is desired in a variety of practical applications such as optical metrology, nondestructive testing, and quantitative microscopy etc. Several methods have been proposed to quantitatively measure the phase and among them interferometry is a commonly used technique. Intensity interferometer has also been used to recover the phase and enhance the phase difference measurement by the intensity correlation. In this paper, we present and examine another technique based on the Stokes correlation for enhancing the phase measurement by a factor of two. Enhancement in phase measurement is accomplished by the evaluation of the correlation between two points of Stokes fluctuations of the randomly scattered light and recovering the enhanced phase of the object by using three steps phase- shifting along with the Stokes correlations. This technique is expected to be useful in the experimental measurement of the phase of a weak signal and in the imaging.