Figure 5
From: Fabricating THz spiral zone plate by high throughput femtosecond laser air filament direct writing
Spatial resolution performance measured by fabricating resolution test chart array on an aluminum foil sample. (a) Schematic diagram of the resolution chart array that will be written onto the sample surface; (b) photo of the fabricated resolution chart array on the sample; (c) enlarged image of the resolution chart fabricated at the edge of the fabrication region; (d) distribution of the fabrication resolution in the XOY plane; each resolution chart stands for an area of 20 × 20 mm2, and its position is one-to-one corresponding to (b).
