您选择的条件: Guoan Zheng
  • Resolution-enhanced parallel coded ptychography for high-throughput optical imaging

    分类: 光学 >> 量子光学 提交时间: 2023-02-19

    摘要: Ptychography is an enabling coherent diffraction imaging technique for both fundamental and applied sciences. Its applications in optical microscopy, however, fall short for its low imaging throughput and limited resolution. Here, we report a resolution-enhanced parallel coded ptychography technique achieving the highest numerical aperture and an imaging throughput orders of magnitude greater than previous demonstrations. In this platform, we translate the samples across the disorder-engineered surfaces for lensless diffraction data acquisition. The engineered surface consists of chemically etched micron-level phase scatters and printed sub-wavelength intensity absorbers. It is designed to unlock an optical space with spatial extent (x, y) and frequency content (kx, ky) that is inaccessible using conventional lens-based optics. To achieve the best resolution performance, we also report a new coherent diffraction imaging model by considering both the spatial and angular responses of the pixel readouts. Our low-cost prototype can directly resolve 308-nm linewidth on the resolution target without aperture synthesizing. Gigapixel high-resolution microscopic images with a 240-mm^2 effective field of view can be acquired in 15 seconds. For demonstrations, we recover slow-varying 3D phase objects with many 2{\pi} wraps, including optical prism and convex lens. The low-frequency phase contents of these objects are challenging to obtain using other existing lensless techniques. For digital pathology applications, we perform accurate virtual staining by using the recovered phase as attention guidance in a deep neural network. Parallel optical processing using the reported technique enables novel optical instruments with inherent quantitative nature and metrological versatility.

  • Ptychographic sensor for large-scale lensless microbial monitoring with high spatiotemporal resolution

    分类: 光学 >> 量子光学 提交时间: 2023-02-19

    摘要: Traditional microbial detection methods often rely on the overall property of microbial cultures and cannot resolve individual growth event at high spatiotemporal resolution. As a result, they require bacteria to grow to confluence and then interpret the results. Here, we demonstrate the application of an integrated ptychographic sensor for lensless cytometric analysis of microbial cultures over a large scale and with high spatiotemporal resolution. The reported device can be placed within a regular incubator or used as a standalone incubating unit for long-term microbial monitoring. For longitudinal study where massive data are acquired at sequential time points, we report a new temporal-similarity constraint to increase the temporal resolution of ptychographic reconstruction by 7-fold. With this strategy, the reported device achieves a centimeter-scale field of view, a half-pitch spatial resolution of 488 nm, and a temporal resolution of 15-second intervals. For the first time, we report the direct observation of bacterial growth in a 15-second interval by tracking the phase wraps of the recovered images, with high phase sensitivity like that in interferometric measurements. We also characterize cell growth via longitudinal dry mass measurement and perform rapid bacterial detection at low concentrations. For drug-screening application, we demonstrate proof-of-concept antibiotic susceptibility testing and perform single-cell analysis of antibiotic-induced filamentation. The combination of high phase sensitivity, high spatiotemporal resolution, and large field of view is unique among existing microscopy techniques. As a quantitative and miniaturized platform, it can improve studies with microorganisms and other biospecimens at resource-limited settings.

  • Complex-domain super-resolution imaging with distributed optimization

    分类: 光学 >> 量子光学 提交时间: 2023-02-19

    摘要: Complex-domain imaging has emerged as a valuable technique for investigating weak-scattered samples. However, due to the detector's pursuit of large pixel size for high throughput, the resolution limitation impedes its further development. In this work, we report a lensless on-chip complex-domain imaging system, together with a distributed-optimization-based pixel super-resolution technique (DO-PSR). The system employs a diffuser shifting to realize phase modulation and increases observation diversity. The corresponding DO-PSR technique derives an alternating projection operator and an enhancing neural network to tackle the measurement fidelity and statistical prior regularization subproblems. Extensive experiments show that the system outperforms the existing techniques with as much as 11dB on PSNR, and one-order-of-magnitude higher cell counting precision.

  • 运营单位: 中国科学院文献情报中心
  • 制作维护:中国科学院文献情报中心知识系统部
  • 邮箱: eprint@mail.las.ac.cn
  • 地址:北京中关村北四环西路33号
招募志愿者 许可声明 法律声明

京ICP备05002861号-25 | 京公网安备11010802041489号
版权所有© 2016 中国科学院文献情报中心