Human action recognition(HAR)is crucial for the development of efficient computer vision,where bioinspired neuromorphic perception visual systems have emerged as a vital solution to address transmission bottlenecks ac...Human action recognition(HAR)is crucial for the development of efficient computer vision,where bioinspired neuromorphic perception visual systems have emerged as a vital solution to address transmission bottlenecks across sensor-processor interfaces.However,the absence of interactions among versatile biomimicking functionalities within a single device,which was developed for specific vision tasks,restricts the computational capacity,practicality,and scalability of in-sensor vision computing.Here,we propose a bioinspired vision sensor composed of a Ga N/Al N-based ultrathin quantum-disks-in-nanowires(QD-NWs)array to mimic not only Parvo cells for high-contrast vision and Magno cells for dynamic vision in the human retina but also the synergistic activity between the two cells for in-sensor vision computing.By simply tuning the applied bias voltage on each QD-NW-array-based pixel,we achieve two biosimilar photoresponse characteristics with slow and fast reactions to light stimuli that enhance the in-sensor image quality and HAR efficiency,respectively.Strikingly,the interplay and synergistic interaction of the two photoresponse modes within a single device markedly increased the HAR recognition accuracy from 51.4%to 81.4%owing to the integrated artificial vision system.The demonstration of an intelligent vision sensor offers a promising device platform for the development of highly efficient HAR systems and future smart optoelectronics.展开更多
In this work,we design and fabricate a deep ultraviolet(DUV)light-emitting array consisting of 10×10 micro-LEDs(μ-LEDs)with each device having 20μm in diameter.Strikingly,the array demonstrates a significant en...In this work,we design and fabricate a deep ultraviolet(DUV)light-emitting array consisting of 10×10 micro-LEDs(μ-LEDs)with each device having 20μm in diameter.Strikingly,the array demonstrates a significant enhancement of total light output power by nearly 52%at the injection current of 100 mA,in comparison to a conventional large LED chip whose emitting area is the same as the array.A much higher(~22%)peak external quantum efficiency,as well as a smaller efficiency droop forμ-LED array,was also achieved.The numerical calculation reveals that the performance boost can be attributed to the higher light extraction efficiency at the edge of eachμ-LED.Additionally,the far-field pattern measurement shows that theμ-LED array possesses a better forward directionality of emission.These findings shed light on the enhancement of the DUV LEDs performance and provide new insights in controlling the light behavior of theμ-LEDs.展开更多
The Al Ga N-based deep ultraviolet(DUV)light-emitting diode(LED)is an alternative DUV light source to replace traditional mercury-based lamps.However,the state-of-the-art DUV LEDs currently exhibit poor wall-plug effi...The Al Ga N-based deep ultraviolet(DUV)light-emitting diode(LED)is an alternative DUV light source to replace traditional mercury-based lamps.However,the state-of-the-art DUV LEDs currently exhibit poor wall-plug efficiency and low light output power,which seriously hinder their commercialization.In this work,we design and report a tunnel-junctioncascaded(TJC)DUV LED,which enables multiple radiative recombinations within the active regions.Therefore,the light output power of the TJC-DUV LEDs is more than doubled compared to the conventional DUV LED.Correspondingly,the wall-plug efficiency of the TJC-DUV LED is also significantly boosted by 25%at 60 m A.展开更多
基金funded by the National Natural Science Foundation of China(Grant Nos.62322410,52272168,624B2135,61804047)the Fundamental Research Funds for the Central Universities(No.WK2030000103)。
文摘Human action recognition(HAR)is crucial for the development of efficient computer vision,where bioinspired neuromorphic perception visual systems have emerged as a vital solution to address transmission bottlenecks across sensor-processor interfaces.However,the absence of interactions among versatile biomimicking functionalities within a single device,which was developed for specific vision tasks,restricts the computational capacity,practicality,and scalability of in-sensor vision computing.Here,we propose a bioinspired vision sensor composed of a Ga N/Al N-based ultrathin quantum-disks-in-nanowires(QD-NWs)array to mimic not only Parvo cells for high-contrast vision and Magno cells for dynamic vision in the human retina but also the synergistic activity between the two cells for in-sensor vision computing.By simply tuning the applied bias voltage on each QD-NW-array-based pixel,we achieve two biosimilar photoresponse characteristics with slow and fast reactions to light stimuli that enhance the in-sensor image quality and HAR efficiency,respectively.Strikingly,the interplay and synergistic interaction of the two photoresponse modes within a single device markedly increased the HAR recognition accuracy from 51.4%to 81.4%owing to the integrated artificial vision system.The demonstration of an intelligent vision sensor offers a promising device platform for the development of highly efficient HAR systems and future smart optoelectronics.
基金funded by the National Natural Science Foundation of China (Grant Nos. 52161145404, 61905236, 51961145110)the Fundamental Research Funds for the Central Universities (Grant No. WK2100230020)USTC Research Funds of the Double First-Class Initiative (Grant No. YD3480002002)
文摘In this work,we design and fabricate a deep ultraviolet(DUV)light-emitting array consisting of 10×10 micro-LEDs(μ-LEDs)with each device having 20μm in diameter.Strikingly,the array demonstrates a significant enhancement of total light output power by nearly 52%at the injection current of 100 mA,in comparison to a conventional large LED chip whose emitting area is the same as the array.A much higher(~22%)peak external quantum efficiency,as well as a smaller efficiency droop forμ-LED array,was also achieved.The numerical calculation reveals that the performance boost can be attributed to the higher light extraction efficiency at the edge of eachμ-LED.Additionally,the far-field pattern measurement shows that theμ-LED array possesses a better forward directionality of emission.These findings shed light on the enhancement of the DUV LEDs performance and provide new insights in controlling the light behavior of theμ-LEDs.
基金supported by the National Natural Science Foundation of China(No.61905236)the University of Science and Technology of China(No.KY2100000081)+2 种基金the Chinese Academy of Sciences(No.KJ2100230003)the Fundamental Research Funds for the Central Universities(No.WK2100230020)the USTC Research Funds of the Double First-Class Initiative(No.YD3480002002)。
文摘The Al Ga N-based deep ultraviolet(DUV)light-emitting diode(LED)is an alternative DUV light source to replace traditional mercury-based lamps.However,the state-of-the-art DUV LEDs currently exhibit poor wall-plug efficiency and low light output power,which seriously hinder their commercialization.In this work,we design and report a tunnel-junctioncascaded(TJC)DUV LED,which enables multiple radiative recombinations within the active regions.Therefore,the light output power of the TJC-DUV LEDs is more than doubled compared to the conventional DUV LED.Correspondingly,the wall-plug efficiency of the TJC-DUV LED is also significantly boosted by 25%at 60 m A.
