Sponsor(s): Chinese Optical Society；Shanghai Institute of Optics and Fine Mechanics，Chinese Academy of Sciences
12 issues per year
Current Issue: Issue 10, 2018
Acta Optica Sinica(ISSN：0253-2239), founded in 1981, is the optical academic publication issued at home and abroad, which covers the latest research in optical science. The main scopes of this journal include atmospheric and ocean optics, detectors, fiber optics and optical communications, Fourier optics and optical signal processing, holography, imaging systems, measurement and metrology, lasers and laser optics, machine vision, materials, nonlinear optics, optical design and fabrication, optical devices, physical optics, quantum optics, remote sensing and sensors, spectroscopy, X-ray optics, etc. This journal offers service for optical science and technology researcher to carry out academic exchange and discussion. Acta Optica Sinica has been selected into Science Abstracts(SA), Chemical Abstract (CA), Abstract Journal(AJ), Information Service in Physics, Electro-Technology, Computer and Control (INSPEC), Engineering Index (EI), etc, which is one of 100 outstanding academic journals of China.
Gan Fuxi Wang Zhijiang Xu Zhizhan Wang Runwen
Shao Jianda Xu Jinjun Hu Lili Han Shensheng
Executive Editorial Board
Wang Yongtian Liu Shu
Improvement of Universal Dynamic Threshold Cloud Detection Algorithm and Its Application in High-Resolution Satellite
Acta Optica Sinica,2018,Vol 38,No. 10
With the support of a pre-calculated land surface reflectance database, the universal dynamic threshold cloud detection algorithm (UDTCDA) can significantly improve the cloud detection accuracy of satellite data. To further improve its precision in the application of cloud detection for high-spatial-resolution satellite data with relatively few bands, we improve the spatial matching method between the priori surface reflectance and the satellite observed reflectance. Different from the directly resample method in the UDTCDA, the pixel-by-pixel registration method is adopted to realize the matching between the satellite image and surface reflectance image. This approach preserves the spatial resolution advantage of high resolution images, and effectively reduces the loss of pixel information caused by spatial resampling. Four high-resolution satellite data, namely ZY-3, GF-1, GF-2 and GF-4, are used in cloud detection experiments. The cloud detection results of the improved UDTCDA are verified by the visual interpretation cloud results, and compared with the original UDTCDA cloud results. Results show that the improved algorithm can accurately identify different kinds of clouds in different high-resolution satellite images with an average accuracy of 93.92%. Especially for the broken and thin clouds, the accuracy is significantly improved with overall low omission and commission errors less than 10.40% and 9.57%, respectively.
Properties of Multi-frequency Phase Resonance in Double-slit Compound Gratings with Different Slit Widths
Acta Optica Sinica,2018,Vol 38,No. 10
Transmission properties of light through a double-slit compound grating with different slit widths are investigated with the finite-difference time-domain (FDTD) method. The results show that phase resonance (PR) splitting can be achieved with the slit widths modulation, and it can be simultaneously modulated at multiple frequencies. All modes have sharp PR splittings, and the values of some valleys are almost zero. Based on the electromagnetic field distribution, Fabry-Perot resonance and PR mechanism, the physical origins of the observations have been qualitatively described and explained. In addition, we can realize the control of light spreading through any slit in two slits, and also achieve the design of bandgap by splitting valley. These results can be used to design optical channel selector, frequency selector, filter and optical switch. Compared with the conventional compound gratings, this double-slit grating with different slit widths has obvious advantages, such as simple structure, single material, and easy realization, design and analysis.