Fig. 4: Integrated holographic devices based on VCSELs.
a Left: schematic illustration of a holographic VCSEL integrated with metasurface for constructing a university logo image. Right: Experimentally reconstructed image122. b Left: polarization multiplexed holography to display two different holographic images in the far field. Right: calculated transmission amplitude and phase of the selected six meta-atoms. A complete 2π modulation range of propagation phase is achieved124. c Left: SEM images of the integrated holographic metasurface. The inset schematically summarizes the example of dual-channel holographic design to structure the far-field intensity profiles of the polarization-decoupled VCSEL into two channels, in which two infrared images of the letters of “BJUT” and the university logo were directly projected onto a white screen for observation124. Right: the recorded far-field beam patterns without and with a polarizer, in which the uncontrolled co-polarization channel can be filtered out using a polarizer. d The divergent co-polarization beam spot can be removed from the holographic images with a polarizer, revealing the hidden information124. Figure a is adapted from ref. 122 with permission from the John Wiley and Sons. Figure b–d are adapted from ref. 124. with permission from the Springer Nature by CC BY 4.0
