Holographic displays hold the promise of providing authentic depth cues, resulting in enhanced immersive visual experiences for near-eye applications. However, current holographic displays are hindered by speckle noise, which limits accurate reproduction of color and texture in displayed images. We present HoloChrome, a polychromatic holographic display framework designed to mitigate these limitations. HoloChrome utilizes an ultrafast, wavelength-adjustable laser and a dual-Spatial Light Modulator (SLM) architecture, enabling the multiplexing of a large set of discrete wavelengths across the visible spectrum. By leveraging spatial separation in our dual-SLM setup, we independently manipulate speckle patterns across multiple wavelengths. This novel approach effectively reduces speckle noise through incoherent averaging achieved by wavelength multiplexing. Our method is complementary to existing speckle reduction techniques, offering a new pathway to address this challenge. Furthermore, the use of polychromatic illumination broadens the achievable color gamut compared to traditional three-color primary holographic displays. Our simulations and tabletop experiments validate that HoloChrome significantly reduces speckle noise and expands the color gamut. These advancements enhance the performance of holographic near-eye displays, moving us closer to practical, immersive next-generation visual experiences.

翻译：全息显示器有望提供真实深度线索，从而为近眼应用带来增强的沉浸式视觉体验。然而，当前全息显示器受限于散斑噪声，这制约了显示图像色彩与纹理的精确再现。本文提出HoloChrome——一种旨在缓解上述局限的多色全息显示框架。该系统采用超快波长可调激光器与双空间光调制器（SLM）架构，能够在可见光谱范围内对大量离散波长进行复用。通过双SLM设置中的空间分离设计，我们实现了多波长散斑图案的独立调控。这种创新方法通过波长复用实现非相干叠加，从而有效抑制散斑噪声。本方法与现有散斑抑制技术形成互补，为解决该挑战提供了新路径。此外，相较于传统三基色全息显示系统，多色照明的运用显著扩展了可实现的色域范围。仿真与桌面实验证实，HoloChrome能显著降低散斑噪声并拓宽色域。这些进展提升了全息近眼显示器的性能，推动我们向实用化、沉浸式的新一代视觉体验迈进。