Dual-wavelength digital holographic phase and fluorescence microscopy for an optical thickness encoded suspension array.

A dual-wavelength digital holographic phase and fluorescence microscopy system is demonstrated as the decoding and detection platform of an optical thickness encoded suspension array. The phase imaging path is designed to decode optical thickness encoded microcarriers, and the fluorescence imaging path is used to detect the quantitative information of the bound target analytes. The encoding capacity could be more than 100. The decoding reliability of the phase imaging path is verified by a multiplexed immunoassay experiment. The ability for quantitative analysis of the fluorescence imaging path is confirmed by concentration gradient experiments. This method offers high decoding accuracy and high detection sensitivity of label signals.