Scanning quantitative shear interference microscopy

Quantitative phase microscopy (QPM) has become a widely used technique for in situ analysis of transparent specimens via phase recovery. However, traditional wide-field QPM suffers from reduced contrast and artifact generation due to spatial crosstalk. In this study, we introduce a scanning quantitative shear interference microscopy (SQSIM) that combines a phase-type spatial light modulator (SLM) with laser focus scanning illumination. This method enables phase recovery while effectively avoiding spatial crosstalk. SQSIM boasts a straightforward structure and high stability. It can be easily integrated with various imaging modalities, offering superior versatility. Moreover, SQSIM can precisely achieve variable degrees of shear deviation in any direction, rendering it versatile for diverse objectives and samples. We underscore the superior phase imaging capabilities of SQSIM through both simulations and real-world experiments. We believe that SQSIM presents significant application prospects in both the life science and industrial inspection.