Recovering Image Information from Colored Speckle under RGB Illumination in an Imaging System

Speckle field is one of the most information-rich light fields related to plentiful physical characteristics at present that can be used to provide high-resolution surface topography information or applied to image reconstruction, image enhancement and other fields. However, the most study of speckle image recovery for monochromatic wavelength ignores a large amount of real object information. In this paper, the amplitude information of colored speckle recovery in optical imaging is studied, as might be seen if red, green, and blue lasers illuminate a rough surface with different reflectivity at these three wavelengths. We derived the expression for color speckle distribution and designed an imaging system with a pupil stop, normal plane-wave incidence on the diffuser, and a camera to observe the colored speckled image. In order to analyze the simulation experiment, two aspects are studied: phase shift and average speckle size. The results show that more characteristic information is recovered from the colored speckle image.