摘要
A metasurface hologram combines fine spatial resolution and large viewing angles with a planar form factor and compact size.However,it suffers coherent artifacts originating from electromagnetic cross-talk between closely packed meta-atoms and fabrication defects of nanoscale features.Here,we introduce an efficient method to suppress all artifacts by fine-tuning the spatial coherence of illumination.Our method is implemented with a degenerate cavity laser,which allows a precise and continuous tuning of the spatial coherence over a wide range,with little variation in the emission spectrum and total power.We find the optimal degree of spatial coherence to suppress the coherent artifacts of a meta-hologram while maintaining the image sharpness.This work paves the way to compact and dynamical holographic displays free of coherent defects.
基金
supported by the US Office of Naval Research(ONR)under Grant No.N00014-221-1-2026
support from National Key Research and Development Program of China(Grant No.2018YFB2200403)
National Natural Science Foundation of China(Grant Nos.12025402,11974092,91850204,11934012,and 61975041)
Shenzhen Fundamental research projects(Grant Nos.JCYJ20180507184613841,JCYJ20180507183532343,and JCYJ20180306172041577).