Ultrathin meta-optics utilize subwavelength nano-antennas to modulate incident light with greater design freedom and space-bandwidth product over conventional diffractive optical elements (DOEs) 1, 2, 3, 4.
We turn towards computationally designed metasurface optics (meta-optics) to close this gap and enable ultra-compact cameras that could facilitate new capabilities in endoscopy, brain imaging, or in a distributed fashion as collaborative optical “dust” on scene surfaces. A further fundamental barrier is a difficulty of reducing focal length, as this induces greater chromatic aberrations. Traditional imaging systems consist of a cascade of refractive elements that correct for aberrations, and these bulky lenses impose a lower limit on camera footprint.
While sensors with submicron pixels do exist, further miniaturization has been prohibited by the fundamental limitations of conventional optics. However, imagers that are an order of magnitude smaller could enable numerous novel applications in nano-robotics, in vivo imaging, AR/VR, and health monitoring. The miniaturization of intensity sensors in recent decades has made today’s cameras ubiquitous across many application domains, including medical imaging, commodity smartphones, security, robotics, and autonomous driving. As such, we present a high-quality, nano-optic imager that combines the widest field-of-view for full-color metasurface operation while simultaneously achieving the largest demonstrated aperture of 0.5 mm at an f-number of 2. Experimentally validating the proposed method, we achieve an order of magnitude lower reconstruction error than existing approaches. We devise a fully differentiable learning framework that learns a metasurface physical structure in conjunction with a neural feature-based image reconstruction algorithm. In this work, we close this performance gap by introducing a neural nano-optics imager. Although metasurface optics offer a path to such ultra-small imagers, existing methods have achieved image quality far worse than bulky refractive alternatives, fundamentally limited by aberrations at large apertures and low f-numbers. Nano-optic imagers that modulate light at sub-wavelength scales could enable new applications in diverse domains ranging from robotics to medicine.
0 kommentar(er)
