The equivalent two-port network model of a middle range wireless power transfer(WPT) system was presented based on strongly coupled multiple resonators. The key parameters of the WPT system include self-inductance, re...The equivalent two-port network model of a middle range wireless power transfer(WPT) system was presented based on strongly coupled multiple resonators. The key parameters of the WPT system include self-inductance, resistance, parasitic capacitance, mutual inductance and S-parameters of coils & resonators were analyzed. The impedance matching method was used to optimize load power and transmission efficiency of the multi-resonator WPT system, and the impedance matching method was realized through adjusting the distances between the coils and resonators. Experiments show that the impedance matching method can effectively improve load power and transmission efficiency for middle range wireless power transfer systems with multiple resonators, at distances up to 3 times the coil radius with efficiency more than 70% and load power also close to 3.5 W.展开更多
Complementary metal oxide semiconductor(CMOS) image sensors(CIS) are being widely used in digital video cameras, web cameras, digital single lens reflex camera(DSLR), smart phones and so on, owing to their high level ...Complementary metal oxide semiconductor(CMOS) image sensors(CIS) are being widely used in digital video cameras, web cameras, digital single lens reflex camera(DSLR), smart phones and so on, owing to their high level of integration, random accessibility, and low-power operation. It needs to be installed with the cover glass in practical applications to protect the sensor from damage, mechanical issues,and environmental conditions, which, however, limits the accuracy and usability of the sensor due to the reflection in the optical path from air-to-cover glass-to-air. In this work, the flexible 3D nanocone anti-reflection(AR) film with controlled aspect ratio was firstly employed to reduce the light reflection at air/cover glass/air interfaces by directly attaching onto the front and rear sides of the CIS cover glass.As both the front and rear sides of cover glass were coated by the AR film, the output image quality was found to be improved with external quantum efficiency increased by 7%, compared with that without AR film. The mean digital data value, root-mean-square contrast, and dynamic range are increased by45.14%, 38.61% and 57, respectively, for the output image with AR films. These results provide a novel and facile pathway to improve the CIS performance and also could be extended to rational design of other image sensors and optoelectronic devices.展开更多
基金Project(61104088)supported by the National Natural Science Foundation of ChinaProject(12C0741)supported by Scientific Research Fund of Hunan Provincial Education Department,China
文摘The equivalent two-port network model of a middle range wireless power transfer(WPT) system was presented based on strongly coupled multiple resonators. The key parameters of the WPT system include self-inductance, resistance, parasitic capacitance, mutual inductance and S-parameters of coils & resonators were analyzed. The impedance matching method was used to optimize load power and transmission efficiency of the multi-resonator WPT system, and the impedance matching method was realized through adjusting the distances between the coils and resonators. Experiments show that the impedance matching method can effectively improve load power and transmission efficiency for middle range wireless power transfer systems with multiple resonators, at distances up to 3 times the coil radius with efficiency more than 70% and load power also close to 3.5 W.
基金financially supported by the National Natural Science Foundation of China(61474128,21503261,61504155and 61404145)Youth Innovation Fund for Interdisciplinary Research of SARI(Y526453233,141004)+2 种基金Science & Technology Commission of Shanghai Municipality(14JC1492900,14511102302,15DZ1100502)Youth Innovation Promotion Association,CAS(2013302)Development Fund for Information communication and integrated circuit technology public service platform(No.2016-14)supported by Zhangjiang Adminstrative Committee
文摘Complementary metal oxide semiconductor(CMOS) image sensors(CIS) are being widely used in digital video cameras, web cameras, digital single lens reflex camera(DSLR), smart phones and so on, owing to their high level of integration, random accessibility, and low-power operation. It needs to be installed with the cover glass in practical applications to protect the sensor from damage, mechanical issues,and environmental conditions, which, however, limits the accuracy and usability of the sensor due to the reflection in the optical path from air-to-cover glass-to-air. In this work, the flexible 3D nanocone anti-reflection(AR) film with controlled aspect ratio was firstly employed to reduce the light reflection at air/cover glass/air interfaces by directly attaching onto the front and rear sides of the CIS cover glass.As both the front and rear sides of cover glass were coated by the AR film, the output image quality was found to be improved with external quantum efficiency increased by 7%, compared with that without AR film. The mean digital data value, root-mean-square contrast, and dynamic range are increased by45.14%, 38.61% and 57, respectively, for the output image with AR films. These results provide a novel and facile pathway to improve the CIS performance and also could be extended to rational design of other image sensors and optoelectronic devices.