This is a topography image of a holographic, UV optimized, blazed diffraction grating with 2400 lines/mm. It is a good graphic illustration of how much further at the nanoscale Atomic Force Microscopy allows us to ‘see’ beyond what any optical device could. The ridges diffract visible and near-UV light. To light these ridges are perfectly flat. The AFM using a sharp BudgetSensors tip shows us that their surface is actually quite rough.
Scanned with a BudgetSensors SiNi
AFM probe, long cantilever in contact mode, 3 micron scan size
Image courtesy of Dr. Yordan Stefanov, Innovative Solutions Bulgaria