Bessel Speckles

TL;DR

This paper investigates speckle patterns formed by randomly interfering Bessel beams, revealing their potential for tunable 3D imaging and advancing incoherent imaging technologies.

Contribution

It introduces a fundamental study of Bessel speckles, demonstrating their unique imaging properties and potential for next-generation incoherent imaging applications.

Findings

Bessel speckles exhibit tunable axial resolution.

Long focal depth of Bessel beams is modulated by randomness.

Synthetic 3D imaging demonstrated using Bessel speckles.

Abstract

Speckle patterns are formed by random interferences of mutually coherent beams. While speckles are often considered as an unwanted noise in many areas, they also formed the foundation for the development of numerous speckle-based imaging, holography and sensing technologies. In the recent years, artificial speckle patterns have been generated with spatially incoherent sources using static and dynamic optical modulators for advanced imaging applications. In this report, a fundamental study has been carried out with Bessel distribution as the fundamental building block of the speckle pattern: speckle patterns formed by randomly interfering Bessel beams. Indirect computational imaging framework has been applied to study the imaging characteristics. In general, Bessel beams have a long focal depth, which in this scenario is counteracted by the increase in randomness enabling tunability of the axial resolution between the limits of Bessel beam and a Gaussian beam. Three-dimensional computational imaging has been synthetically demonstrated. The presented study will lead to a new generation of incoherent imaging technologies.