We report the nonlocal imaging of an object by conditional averaging of the random exposure frames of a reference detector,which only sees the freely propagating field from a thermal light source.A bucket detector,syn...We report the nonlocal imaging of an object by conditional averaging of the random exposure frames of a reference detector,which only sees the freely propagating field from a thermal light source.A bucket detector,synchronized with the reference detector,records the intensity fluctuations of an identical beam passing through the object mask.These fluctuations are sorted according to their values relative to the mean,then the reference data in the corresponding time-bins for a given fluctuation range are averaged,to produce either positive or negative images.Since no correlation calculations are involved,this correspondence imaging technique challenges our former interpretations of “ghost” imaging.Compared with conventional correlation imaging or compressed sensing schemes,both the number of exposures and computation time are greatly reduced,while the visibility is much improved.A simple statistical model is presented to explain the phenomenon.展开更多
High-order ghost imaging with thermal light consisting of N different frequencies is investigated. The high-order intensity correlation and intrinsic correlation functions are derived for such N-colour light. It is fo...High-order ghost imaging with thermal light consisting of N different frequencies is investigated. The high-order intensity correlation and intrinsic correlation functions are derived for such N-colour light. It is found that they are similar in form to those for the monochromatic case, thus most of the conclusions we obtained previously for monochromatic Nth-order ghost imaging are still applicable. However, we find that the visibility of the N-colour ghost image depends strongly on the wavelength used to illuminate the object, and increases as this wavelength increases when the test arm is fixed. On the contrary, changes of wavelength in the reference arms do not lead to any change of the visibility.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 60978002the National Basic Research Program of China under Grant Nos 2010CB922904 and 2007CB814800the National High Technology R&D Program of China under Grant No 2011AA120102。
文摘We report the nonlocal imaging of an object by conditional averaging of the random exposure frames of a reference detector,which only sees the freely propagating field from a thermal light source.A bucket detector,synchronized with the reference detector,records the intensity fluctuations of an identical beam passing through the object mask.These fluctuations are sorted according to their values relative to the mean,then the reference data in the corresponding time-bins for a given fluctuation range are averaged,to produce either positive or negative images.Since no correlation calculations are involved,this correspondence imaging technique challenges our former interpretations of “ghost” imaging.Compared with conventional correlation imaging or compressed sensing schemes,both the number of exposures and computation time are greatly reduced,while the visibility is much improved.A simple statistical model is presented to explain the phenomenon.
基金supported by the National Natural Science Foundation of China (Grant No. 60978002)the National Fundamental Research Programme of China (Grant Nos. 2006CB921107 and 2010CB922904)
文摘High-order ghost imaging with thermal light consisting of N different frequencies is investigated. The high-order intensity correlation and intrinsic correlation functions are derived for such N-colour light. It is found that they are similar in form to those for the monochromatic case, thus most of the conclusions we obtained previously for monochromatic Nth-order ghost imaging are still applicable. However, we find that the visibility of the N-colour ghost image depends strongly on the wavelength used to illuminate the object, and increases as this wavelength increases when the test arm is fixed. On the contrary, changes of wavelength in the reference arms do not lead to any change of the visibility.