Figure 3
From: Highly efficient multicolor multifocus microscopy by optimal design of diffraction binary gratings

Fabrication and characterization of the 0.84 × π grating. (a) Electron microscopy image of the resulted grating showing a good border definition of the different etching zones. (b) Scanning AFM image of the heights of the gratings as a convolution of the physical size of the tip and the real structure of the grating. The cross section along the blue line is presented in (c).