Microlens array-based light-field imaging has been one of the most commonly used and effective technologies to record high-dimensional optical signals for developing various potential high-performance applications in many fields. However, the use of a microlens array generally suffers from an intrinsic trade-off between the spatial and angular resolutions. In this paper, we concentrate on exploiting a diffuser to explore a novel modality for light-field imaging. We demonstrate that the diffuser can efficiently angularly couple incident light rays into a detected image without needing any lens. To characterize and analyse this phenomenon, we establish a diffuser-encoding light-field transmission model, in which four-dimensional light fields are mapped into two-dimensional images via a transmission matrix describing the light propagation through the diffuser. Correspondingly, a calibration strategy is designed to flexibly determine the transmission matrix, so that light rays can be computationally decoupled from a detected image with adjustable spatio-angular resolutions, which are unshackled from the resolution limitation of the sensor. The proof-of-concept approach indicates the possibility of using scattering media for lensless four-dimensional light-field recording and processing, not just for two- or three-dimensional imaging.

基于微透镜阵列的光场成像已成为记录高维光信号最常用、最有效的技术之一，可在许多领域开发各种潜在的高性能应用。然而，微透镜阵列的使用通常会受到空间分辨率和角度分辨率之间的内在权衡的影响。在本文中，我们专注于利用漫射器来探索光场成像的新模式。我们证明，漫射器可以有效地将入射光线以角度方式耦合到检测到的图像中，而无需任何透镜。为了表征和分析这种现象，我们建立了漫射器编码光场传输模型，其中四维光场通过描述光通过漫射器传播的传输矩阵映射成二维图像。相应地，设计了一种校准策略来灵活地确定传输矩阵，以便可以通过计算将光线与具有可调空间角分辨率的检测到的图像解耦，从而摆脱传感器分辨率的限制。概念验证方法表明可以使用散射介质进行无透镜四维光场记录和处理，而不仅仅是二维或三维成像。