ABSTRACT
This study presents a dual-modality microscopic imaging approach that combines quantitative phase microscopy (QPM) and fluorescence microscopy (FM) based on structured illumination (SI) to provide both structural and functional information for the same sample. As the first imaging modality, structured illumination digital holographic microscopy (SI-DHM) is implemented along the transmission beam path. SI-DHM acts as a label-free, non-invasive approach and provides high-contrast and quantitative phase images utilizing the refractive index contrast of the inner structures of samples against the background. As the second imaging modality, structured illumination (fluorescence) microscopy (SIM) is constructed along the reflection beam path. SIM utilizes fluorescent labeling and provides super-resolution images for specific functional structures of samples. We first experimentally demonstrated phase imaging of SI-DHM on rice leaves and fluorescence (SIM) imaging on mouse kidney sections. Then, we demonstrated dual-modality imaging of biological samples, using DHM to acquire the overall cell morphology and SIM to get specific functional structures. These results prove that the proposed technique is of great importance in biomedical studies, such as providing deep insights into the cell physiology by visualizing and quantifying subcellular structures.
