- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Ultrathin wide-angle large-area digital 3D holographic display using a non-periodic photon sieve
摘要： Holographic displays can provide a 3D visual experience to multiple users without requiring special glasses. By precisely tailoring light fields, holographic displays could resemble realistic 3D scenes with full motion parallax and continuous depth cues. However, available holographic displays are unable to generate such scenes given practical limitations in wavefront modulation. In fact, the limited diffraction angle and small number of pixels of current wavefront modulators derive into a 3D scene with small size and narrow viewing angle. We propose a flat-panel wavefront modulator capable of displaying large dynamic holographic images with wide viewing angle. Specifically, an ultrahigh-capacity non-periodic photon sieve, which diffracts light at wide angles, is combined with an off-the-shelf liquid crystal display panel to generate holographic images. Besides wide viewing angle and large screen size, the wavefront modulator provides multi-colour projection and a small form factor, which suggests the possible implementation of holographic displays on thin devices.
关键词： 3D visualization,photon sieve,wide viewing angle,wavefront modulation,holographic displays
更新于2025-11-25 10:30:42
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Metasurfaces for Terahertz Wavefront Modulation: a Review
摘要： Metasurface is an artificial material composed of a series of subwavelength structure units and has unique electromagnetic characteristics. Based on the ability of manipulating the phase, amplitude, and polarization of electromagnetic wave, various kinds of metasurfaces are designed to realize wavefront manipulations, such as beam focusing, beam steering, vector beams generating, and holographic imaging. This paper reviews the design methods of metasurfaces for wavefront modulation and evolution of the metasurfaces designed for wavefront manipulation in the terahertz (THz) region. The metasurfaces can be divided into two categories: passive and active metasurfaces. For the passive metasurfaces, the single-functional metasurfaces, multifunctional metasurfaces, and high diffraction efficient metasurfaces designed for various THz wavefront shaping, such as focusing, imaging, and special beams generating, are reviewed. For the active metasurfaces, the metasurfaces with fixed structure and all-optical metasurfaces without fixed structure for THz wavefront modulation are summarized. Furthermore, a comparison on the performance of different kinds of metasurfaces for THz wavefront modulation is presented and the development direction and challenges of the THz wavefront modulation metasurfaces in the future are discussed.
关键词： Active metasurface,Wavefront modulation,Terahertz,Passive metasurface
更新于2025-09-23 15:19:57
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A remote laser focusing system with spatial light modulator
摘要： This paper designs a remote laser focusing system (RLFS) based on spatial light modulator (SLM). In this system, the SLM serves as an active optical element that modulates the wavefront of the laser beam, causing variation in beam transmission. Theoretical analysis shows that a reflective SLM can compensate the residual aberrations at different operating distances, enabling the accurate focusing of targets without sacrificing the energy convergence. Based on optical design software, the geometrical parameters were optimized for the presented system through simulation. Finally, experimental demonstration and error analysis were carried out. The results show that the proposed RLFS-SLM is more stable and capable for controlling energy convergence than the traditional mechanical RLFS. Our system provides a desirable tool for high-energy laser applications.
关键词： Remote laser focusing (RLF),Wavefront modulation,Spatial light modulator (SLM),Mechanical focusing
更新于2025-09-23 15:19:57
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Metal-graphene hybrid active chiral metasurfaces for dynamic terahertz wavefront modulation and near field imaging
摘要： Chiral metasurfaces can achieve giant chiral optical responses and have been expanded from the optical band to other electromagnetic bands. Here, we propose a new method for dynamic terahertz circular dichroism (CD) manipulation in metasurfaces. By introducing a patterned and electrically doped graphene into the metamirror consists of double layer C-shaped split ring resonators (SRRs), efficient terahertz CD modulation is observed. Since the electrical doping of graphene changes the absorption loss of the metasuface cavity, the structure shows switching between a chiral metasurface and an ordinary metal mirror, which can be seen as "on" and "off" states. The calculation results show an efficient modulation of the terahertz CD in a large dynamic range. In addition, we also use the new method to design two metasurfaces for dynamic terahertz wavefront modulation and near-field digital imaging, both of which show a high-performance electrical switching. This method provides a new way for the design of active terahertz devices based on metasurfaces, and also promotes the applications of terahertz chiral metasurfaces in high-speed wireless communication and dynamic imaging.
关键词： Chiral metasurfaces,terahertz,circular dichroism,near-field imaging,graphene,wavefront modulation
更新于2025-09-19 17:13:59