Double-Freeform Lens Design for Angular-Spatial Control of Light Fields

TL;DR

This paper introduces a novel single-lens design with double freeform surfaces for precise angular and spatial light-field control, simplifying optical systems while maintaining high performance.

Contribution

It presents a unified optimization framework for designing a single-lens system that controls both angular and spatial light distributions simultaneously.

Findings

Numerical simulations confirm accurate angular-spatial light control.

The method achieves performance comparable to multi-lens systems.

The design simplifies optical setups without sacrificing quality.

Abstract

Precise simultaneous control of both angular and spatial light-field distributions remains a longstanding challenge in optical design, often requiring complex multi-element configurations. In this work, we propose a compact single-lens solution that achieves unified angular-spatial modulation through the co-optimization of double freeform surfaces. The problem is formulated as an extended caustic design that enforces prescribed irradiance patterns on two distinct receptive planes, where the dual-plane constraint implicitly defines the directional characteristics of the light field while preserving spatial accuracy. This framework eliminates the need for auxiliary optical components while delivering performance comparable to that of conventional multi-lens systems. Comprehensive numerical simulations verify the method's effectiveness, demonstrating accurate and stable control of both angular and spatial light-field properties. The proposed approach establishes a practical foundation for compact, high-performance optical systems and provides a promising route toward integrated angular-spatial light-field engineering.