Abstract
Atomic force microscopy (AFM) is essential for studying the surface
properties of samples at the micro- and nanoscales. Traditional AFM
scanning methods are time-consuming, particularly for obtaining
high-resolution images. Compressive sensing (CS) has been utilized for
fast AFM imaging. However, as the size and resolution requirements of
the images increase, the measurement matrix for compressive sensing also
becomes larger. Block compressive sensing (BCS) divides the image into
blocks and reconstructs them with a small measurement matrix, but it is
difficult to balance the imaging quality between regions. Therefore, we
propose an innovative adaptive CS-AFM imaging scheme. A low-resolution
image is obtained through fast scanning, and a high-resolution image is
generated using bicubic interpolation. The Otsu and eight-connectivity
methods detect the location of the target blocks, while the GRNN model
adapts the sampling rate for it. Supplementary scan is performed on the
target block, followed by reconstruction using the TVAL3 algorithm.
Finally, the target region is replaced with the reconstructed
high-quality target blocks. Compared to other schemes, the results
demonstrate that our method excels in achieving fast, high-quality, and
high-resolution imaging.