The seemingly simple step of molding a cholesteric liquid crystal into spherical shape, yielding a Cholesteric Spherical Reflector (CSR), has profound optical consequences that open a range of opportunities for potentially transformative technologies. The chiral Bragg diffraction resulting from the helical self-assembly of cholesterics becomes omnidirectional in CSRs. This turns them into selective retroreflectors that are exceptionally easy to distinguish—regardless of background—by simple and low-cost machine vision, while at the same time they can be made largely imperceptible to human vision. This allows them to be distributed in human-populated environments, laid out in the form of QR-code-like markers that help robots and Augmented Reality (AR) devices to operate reliably, and to identify items in their surroundings. At the scale of individual CSRs, unpredictable features within each marker turn them into Physical Unclonable Functions (PUFs), of great value for secure authentication. Via the machines reading them, CSR markers can thus act as trustworthy yet unobtrusive links between the physical world (buildings, vehicles, packaging,…) and its digital twin computer representation. This opens opportunities to address pressing challenges in logistics and supply chain management, recycling and the circular economy, sustainable construction of the built environment, and many other fields of individual, societal and commercial importance.

将胆甾型液晶成型为球形的看似简单的步骤，产生胆甾型球面反射器（CSR），具有深远的光学后果，为潜在的变革性技术开辟了一系列机会。由胆甾醇的螺旋自组装产生的手性布拉格衍射在 CSR 中变得全向。这将它们变成了选择性后向反射器，无论背景如何，通过简单和低成本的机器视觉都非常容易区分，同时它们可以在很大程度上不被人类视觉感知。这使它们能够分布在人类居住的环境中，以类似 QR 码的标记的形式布置，帮助机器人和增强现实 (AR) 设备可靠地运行，并识别周围的物品。在单个 CSR 的规模上，每个标记中不可预测的特征将它们变成物理不可克隆函数 (PUF)，对安全认证具有重要价值。通过机器读取它们，CSR 标记因此可以充当物理世界（建筑物、车辆、包装……）与其数字孪生计算机表示之间的可靠但不显眼的链接。这为解决物流和供应链管理、回收和循环经济、建筑环境的可持续建设以及许多其他具有个人、社会和商业重要性的领域的紧迫挑战提供了机会。