Fig. 3

Microscopic images and experimental results of fabricated metalens. a and b Phase distribution of designed metalens and microscopic image of the fabricated metasurface. c and d Measured normalized intensity distribution of z-x plane and x-y plane at 0.4–0.8 THz. e Corresponding extracted far-field normalized intensity profiles of the horizontal (red line) and vertical (blue line) cross-sections from (d)