In addition to allowing access to subsurface infrastructure, manhole covers help improve urban aesthetics. They accentuate the beauty of the streets with creative patterns, or logos. These coverings highlight the uniqueness of a location, creating a visually pleasing atmosphere and enhancing the overall aesthetics of the urban environment for residents and visitors to enjoy.
In recent years, advancements in nanotechnology have enabled the fabrication of square gratings at the nanoscale. These nanostructures exhibit unique optical properties that can be exploited in applications ranging from biomedical imaging to optical sensing. For instance, square gratings made of nanomaterials can enhance the sensitivity of biosensors, allowing for the detection of low concentrations of biological molecules. This has significant implications for medical diagnostics, as it enables early detection of diseases based on biomolecular interactions.