Large curvature concave metallic mesh with high optical transmittance and strong electromagnetic interference shielding efficiency

Metallic mesh is widely used in the window and domes of infrared optical system of weapon equipment, the fabrication of planar metallic mesh has been relatively mature. However, it is difficult to prepare the mesh with several microns linewidth uniformly on the concave structure with large curvature. Here we designed and fabricated copper film metal grid with high optical transmittance and strong electromagnetic shielding effect on large concave surface by laser direct writing lithography. It achieves an average shielding efficiency of ~ 27.84 dB in 2-12 GHz frequency band, optical transmittance of ~ 90% in the near infrared band. The simulation and experiment has good uniformity. Our results may provide new ideas for the preparation of the electromagnetic interference shielding metallic mesh. It can improve the service life of weapon equipment receiving window and the ability of infrared imaging tracking and anti-electromagnetic interference.