A 10x10 grid of 100μm squares drawn using the #repRapMicron #3Dprinter.
Etched into a layer of marker on a glass slide.
A 10x10 grid of 100μm squares drawn using the #repRapMicron #3Dprinter.
Etched into a layer of marker on a glass slide.
Tried a diffraction grating?
Closely scribed lines on glass or plastic should work. Opacity is undesirable.