Single‐Shot Wavefront Sensing with Nonlocal Thin Film Optical Filters

Abstract

Conventional wavefront sensors suffer from the fundamental limitation of the space‐bandwidth product and have a trade‐off between their spatial sampling interval and dynamic range. Here, nonlocal thin film optical filters with optimized angle‐ and polarization‐dependent responses are leveraged to circumvent the fundamental limitation, and a robust single‐shot wavefront sensing system with a small spatial sampling interval of 6.9 µm and a large angular dynamic range of 15° is realized. The system only requires inserting two multilayer dielectric filters, fabricated using a mature thin film deposition technique, into a conventional 4‐f imaging apparatus. The polarization‐sensitive nonlocal filters are used to map the 2D phase gradients of the incident light field to the intensity variation of the x‐ and y‐polarized light, respectively, thus enabling single‐shot 2D wavefront reconstruction from images taken by a polarization camera. Such a system may be used for a variety of applications, including high‐resolution image aberration correction, surface metrology, and quantitative phase imaging.

Single-shot deterministic complex amplitude imaging with a single-layer metalens

“…Compared to conventional refractive or diffractive optical elements, it can be manufactured by a single-step lithography process and is extremely versatile in manipulating the vectorial light field ( 19 – 28 ). Recently, metasurfaces ( 29 – 36 ) and thin-film optical devices ( 37 – 39 ) with nonlocal (angle-dependent) responses have been investigated for phase visualization and QPI. Most related to this study, a delicately aligned bilayer metasurface has been implemented to construct a quantitative phase gradient microscope ( 40 ), which can capture the one-dimensional (1D) phase gradient of the target object in a single shot.…”

Metalens for Accelerated Optoelectronic Edge Detection under Ambient Illumination

“…37−39 Furthermore, recently multilayer thin films have been demonstrated to be an even more straightforward platform for ATF manipulation toward applications including but not limited to image differentiation, 40−43 space compression, 44 and wavefront sensing. 45 Those compact nanophotonic devices can be conveniently integrated with a camera sensor, forming a miniature and lightweight edge detection system. Nonetheless, one of the major challenges of most demonstrated optical edge detection systems is that they typically require coherent laser light for illumination, whereas most imaging systems in practical applications use ambient incoherent light for illumination.…”

“…However, using multiple optical elements results in a complex and bulky system. Recently, metasurface, a new class of planar diffractive elements composed of an array of sub-wavelength meta-atoms, has been proposed to greatly shrink the size and complexity of an optical system. − Compact optical systems for image differentiation have been realized using a nonlocal metasurface with an angle-dependent response to mimic first- or second-order spatial differentiation. − Alternatively, one can leverage the spin–orbital interaction or spiral phase generated by a metasurface for edge detection. − Furthermore, recently multilayer thin films have been demonstrated to be an even more straightforward platform for ATF manipulation toward applications including but not limited to image differentiation, − space compression, and wavefront sensing . Those compact nanophotonic devices can be conveniently integrated with a camera sensor, forming a miniature and lightweight edge detection system.…”