High spatial and temporal resolution synthetic aperture phase microscopy

• Main Authors: Zheng, Cheng (Author), Jin, Di (Author), He, Yanping (Author), Lin, Hongtao (Author), Hu, Juejun (Author), Yaqoob, Zahid (Author), So, Peter TC (Author), Zhou, Renjie (Author)
• Format: Article
• Language: English
• Published: SPIE-Intl Soc Optical Eng, 2022-01-25T13:44:39Z.
• Subjects: Article
• Online Access: Get fulltext

 A new optical microscopy technique, termed high spatial and temporal resolution synthetic aperture phase microscopy (HISTR-SAPM), is proposed to improve the lateral resolution of wide-field coherent imaging. Under plane wave illumination, the resolution is increased by twofold to around 260 nm, while achieving millisecond-level temporal resolution. In HISTR-SAPM, digital micromirror devices are used to actively change the sample illumination beam angle at high speed with high stability. An off-axis interferometer is used to measure the sample scattered complex fields, which are then processed to reconstruct high-resolution phase images. Using HISTR-SAPM, we are able to map the height profiles of subwavelength photonic structures and resolve the period structures that have 198 nm linewidth and 132 nm gap (i.e., a full pitch of 330 nm). As the reconstruction averages out laser speckle noise while maintaining high temporal resolution, HISTR-SAPM further enables imaging and quantification of nanoscale dynamics of live cells, such as red blood cell membrane fluctuations and subcellular structure dynamics within nucleated cells. We envision that HISTR-SAPM will broadly benefit research in material science and biology.