Center for Relativistic Laser Science

2017 ABC

Precision measurement for morphology of macroscopic objects has played an important role in many applications. We demonstrated a method for high-resolution macroscopy through a scattering layer. For a macroscopic scale test target, a Julian plaster model was used in the experiment. The height and width of the model were 6 cm and 3 cm, respectively, and its thickness along the axial direction was about 2 cm. using a 2-axis galvanometer mirror, multiple time-gated reflection images were taken at various angles of illumination and the object information was enhanced by synthesizing the object apertures in a coherent fashion. By combining time-gated detection with synthetic aperture microscopy, the single-scattered waves, which contain the correct object information, can be greatly enhanced beyond the background noise generated by multiple scattering. Due to the extension of the aperture, the lateral resolution was improved by a factor of about 2. In addition, this resulted in collective accumulation of single-scattered waves form the object and consequently enhanced the SNR beyond that achieved by the method of incoherent addition. Thus, the object image, which was not resolvable by the incoherent addition, could be successfully retrieved with a reasonable imaging quality.