Experimental demonstration of high compression of space by optical spaceplates

TL;DR

This paper reports the first experimental realization of an optical spaceplate that achieves unprecedented space compression ratios, enabling more compact optical systems with customizable bandwidth and angular range.

Contribution

The authors demonstrate the first engineered multilayer optical spaceplate with high compression ratios, supporting mass production and customizable optical properties.

Findings

Achieved a space compression ratio of up to 176±14.

Demonstrated multilayer stacks support mass production.

Enabled customizable bandwidth and angular range.

Abstract

The physical size of optical imaging systems is one of the greatest constraints on their use, limiting the performance and deployment of a range of systems from telescopes to mobile phone cameras. Spaceplates are nonlocal optical devices that compress free-space propagation into a shorter distance, paving the way for more compact optical systems, potentially even thin flat cameras. Here, we demonstrate the first engineered optical spaceplate and experimentally observe the highest space compression ratios yet demonstrated in any wavelength region, up to $\mathcal{R}=176\pm14$, which is 29 times higher than any previous device. Our spaceplate is a multilayer stack, a well-established commercial fabrication technology that supports mass production. The versatility of these stacks allows for the freedom to customize the spaceplate's bandwidth and angular range, impossible with previous optical experimental spaceplates, which were made of bulk materials. With the appropriate choice of these two parameters, multilayer spaceplates have near-term applications in light detection and ranging (LIDAR) technologies, retinal scanners, endoscopes, and other size-constrained optical devices.