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.

超表面全息图将精细的空间分辨率和大视角与平面形状因数和紧凑的尺寸相结合。然而，其遭受了由于紧密堆积的亚原子与纳米级特征的制造缺陷之间的电磁串扰而引起的相干伪像。在这里，我们介绍一种通过微调照明的空间相干性来抑制所有伪像的有效方法。我们的方法是用简并腔激光器实现的，该激光器允许在宽范围内精确连续地调整空间相干性，而发射光谱和总功率几乎没有变化。我们找到了最佳的空间相干度，以抑制亚全息图的相干伪像，同时保持图像的清晰度。这项工作为紧凑而动态的全息显示铺平了道路，而这些全息显示没有相干的缺陷。