Li Wei's team from the Changchun Institute of Optics, Precision Mechanics and Physics, Chinese Academy of Sciences has made important progress in the field of high-dimensional optical field detection. On May 15th, the related research results were published in Nature under the title of Dispersion assisted High dimensional Photodetector.
The light field contains information from multiple dimensions such as intensity, polarization, frequency, phase, etc. Among them, spectral detection and polarization detection contain information on the material composition and surface morphology of objects, and have application value in fields such as optical communication, remote sensing, industrial detection, medical diagnosis, chemical analysis, and environmental protection. However, traditional photodetectors are limited to measuring light intensity, and existing polarization and spectral detectors typically integrate multiple polarization or wavelength sensitive elements in time or space to enhance detection capabilities. In addition, current polarization and spectral detectors are usually only able to measure intensity and wavelength information under fixed wavelength or uniform polarization. However, in many natural scenarios, the light field may carry arbitrary polarization and intensity changes over a wide spectral range, and existing detectors are difficult to detect this high-dimensional information.
In response to this issue, Li Wei's team and collaborators have, for the first time internationally, comprehensively characterized high-dimensional light fields with arbitrary polarization and intensity changes in the broadband spectral range through a single measurement using a single device, achieving high-dimensional light field information detection.
This study proposes an innovative idea of utilizing the spatial and frequency dispersion characteristics of optical interfaces to regulate polarization and spectral response in wave vector space, which can map all high-dimensional optical field information into single imaging results. The study collaborates with deep learning methods to decode polarization and spectral information, achieving the detection of high-dimensional optical information with detection accuracy comparable to existing advanced single function small polarizers or spectrometers. In addition, research has shown that by simply combining thin films with microlens arrays and imaging sensor arrays in a "sandwich" style, a super integrated high-dimensional optical field imager can be achieved without the need for alignment and single measurement. This achievement has opened up new avenues for ultra compact, high-dimensional information detection and imaging detection.
Research has found that this method has the potential for ultra wideband detection; By utilizing the response capability of this wave vector space, this method can be further integrated with image processing, ranging and other functions to achieve higher dimensional light field detection. Meanwhile, research has shown that replacing thin film structures with photonic crystals, metasurfaces, two-dimensional materials, etc. can further improve detection resolution and integration capabilities. In addition, the future research direction is to organically combine the physical models with deep learning to enhance solving ability and reduce the required amount of prior data.
This work was completed in collaboration between Changchun Institute of Optics and Mechanics and National University of Singapore. Changchun Institute of Optics and Mechanics is the first completion unit.
Paper link
Schematic diagram of the working principle of high-dimensional light field detection method
