Endoscopes are an important component for the development of minimally invasive surgeries.Their size is one of the most critical aspects,because smaller and less rigid endoscopes enable higher agility,facilitate large...Endoscopes are an important component for the development of minimally invasive surgeries.Their size is one of the most critical aspects,because smaller and less rigid endoscopes enable higher agility,facilitate larger accessibility,and induce less stress on the surrounding tissue.In all existing endoscopes,the size of the optics poses a major limitation in miniaturization of the imaging system.Not only is making small optics difficult,but their performance also degrades with downscaling.Meta-optics have recently emerged as a promising candidate to drastically miniaturize optics while achieving similar functionalities with significantly reduced size.Herein,we report an inverse-designed meta-optic,which combined with a coherent fiber bundle enables a 33%reduction in the rigid tip length over traditional gradient-index(GRIN)lenses.We use the meta-optic fiber endoscope(MOFIE)to demonstrate real-time video capture in full visible color,the spatial resolution of which is primarily limited by the fiber itself.Our work shows the potential of meta-optics for integration and miniaturization of biomedical devices towards minimally invasive surgery.展开更多
1 Results Nanometer-scale electrodes with a nano-junction allow us to investigate conduction properties of nano-materials. Because many nano-materials usually form grain boundaries or domain boundaries with high tunne...1 Results Nanometer-scale electrodes with a nano-junction allow us to investigate conduction properties of nano-materials. Because many nano-materials usually form grain boundaries or domain boundaries with high tunneling resistance, it is difficult to investigate the intrinsic properties through a series of tunneling resistance. To make direct contact with the single nano-material, such as a single polymer string, we developed nano-scale electrodes. By using these nano-electrodes as new tool, we invest...展开更多
原子力显微镜(atomic force microscope,AFM)纳米沉积加工是一种重要的纳米焊接手段,其加工机理存在场致蒸发和热致蒸发两种可能.为明确AFM沉积加工的机理,本文通过仿真研究了AFM纳米沉积加工过程中的温度变化,分析了加工电流的波形和...原子力显微镜(atomic force microscope,AFM)纳米沉积加工是一种重要的纳米焊接手段,其加工机理存在场致蒸发和热致蒸发两种可能.为明确AFM沉积加工的机理,本文通过仿真研究了AFM纳米沉积加工过程中的温度变化,分析了加工电流的波形和空气介质对沉积的影响,并在此基础上建模,分别研究瞬态电流和稳态电流引起的温度变化.通过仿真发现,沉积中温度确有上升,但远没有达到引起热蒸发的程度.验证了AFM纳米沉积加工是基于场蒸发的原理.展开更多
Patterned chemical template consisting of both amine- and methyl-terminated self-assembled monolayers has been fabricated. The deposition of carbon nanotubes is carried out by immerging the patterned substrate into di...Patterned chemical template consisting of both amine- and methyl-terminated self-assembled monolayers has been fabricated. The deposition of carbon nanotubes is carried out by immerging the patterned substrate into dimethylformamide (DMF) solution with suspended carbon nanotubes (CNTs). SEM images show a successful patterned deposition that carbon nanotubes selectively deposit in the area with amino-terminated SAMs due to the strong attract force between the monolayer and the suspended CNTs. This experiment provides an opportunity for manipulating individual CNTs, and represents a sig- nificant step in development of CNTs-based nanode- vices.展开更多
Microsystems are increasingly being applied in harsh and/or inaccessible environments,but many markets expect the same level of functionality for long periods of time.Harsh environments cover areas that can be subject...Microsystems are increasingly being applied in harsh and/or inaccessible environments,but many markets expect the same level of functionality for long periods of time.Harsh environments cover areas that can be subjected to high temperature,(bio)-chemical and mechanical disturbances,electromagnetic noise,radiation,or high vacuum.In the field of actuators,the devices must maintain stringent accuracy specifications for displacement,force,and response times,among others.These new requirements present additional challenges in the compensation for or elimination of cross-sensitivities.Many state-of-the-art precision devices lose their precision and reliability when exposed to harsh environments.It is also important that advanced sensor and actuator systems maintain maximum autonomy such that the devices can operate independently with low maintenance.The next-generation microsystems will be deployed in remote and/or inaccessible and harsh environments that present many challenges to sensor design,materials,device functionality,and packaging.All of these aspects of integrated sensors and actuator microsystems require a multidisciplinary approach to overcome these challenges.The main areas of importance are in the fields of materials science,micro/nano-fabrication technology,device design,circuitry and systems,(first-level)packaging,and measurement strategy.This study examines the challenges presented by harsh environments and investigates the required approaches.Examples of successful devices are also given.展开更多
基金supported by NSF-GCR-2120774the National Science Foundation via awards NNCI-1542101 and NNCI-2025489.
文摘Endoscopes are an important component for the development of minimally invasive surgeries.Their size is one of the most critical aspects,because smaller and less rigid endoscopes enable higher agility,facilitate larger accessibility,and induce less stress on the surrounding tissue.In all existing endoscopes,the size of the optics poses a major limitation in miniaturization of the imaging system.Not only is making small optics difficult,but their performance also degrades with downscaling.Meta-optics have recently emerged as a promising candidate to drastically miniaturize optics while achieving similar functionalities with significantly reduced size.Herein,we report an inverse-designed meta-optic,which combined with a coherent fiber bundle enables a 33%reduction in the rigid tip length over traditional gradient-index(GRIN)lenses.We use the meta-optic fiber endoscope(MOFIE)to demonstrate real-time video capture in full visible color,the spatial resolution of which is primarily limited by the fiber itself.Our work shows the potential of meta-optics for integration and miniaturization of biomedical devices towards minimally invasive surgery.
文摘1 Results Nanometer-scale electrodes with a nano-junction allow us to investigate conduction properties of nano-materials. Because many nano-materials usually form grain boundaries or domain boundaries with high tunneling resistance, it is difficult to investigate the intrinsic properties through a series of tunneling resistance. To make direct contact with the single nano-material, such as a single polymer string, we developed nano-scale electrodes. By using these nano-electrodes as new tool, we invest...
文摘原子力显微镜(atomic force microscope,AFM)纳米沉积加工是一种重要的纳米焊接手段,其加工机理存在场致蒸发和热致蒸发两种可能.为明确AFM沉积加工的机理,本文通过仿真研究了AFM纳米沉积加工过程中的温度变化,分析了加工电流的波形和空气介质对沉积的影响,并在此基础上建模,分别研究瞬态电流和稳态电流引起的温度变化.通过仿真发现,沉积中温度确有上升,但远没有达到引起热蒸发的程度.验证了AFM纳米沉积加工是基于场蒸发的原理.
基金This work was supported by the National Key Research Program of China for Fundamental Study(Grant No.2003CB716201)the National Natural Science Foundation of China(Grant No.50390060).
文摘Patterned chemical template consisting of both amine- and methyl-terminated self-assembled monolayers has been fabricated. The deposition of carbon nanotubes is carried out by immerging the patterned substrate into dimethylformamide (DMF) solution with suspended carbon nanotubes (CNTs). SEM images show a successful patterned deposition that carbon nanotubes selectively deposit in the area with amino-terminated SAMs due to the strong attract force between the monolayer and the suspended CNTs. This experiment provides an opportunity for manipulating individual CNTs, and represents a sig- nificant step in development of CNTs-based nanode- vices.
文摘Microsystems are increasingly being applied in harsh and/or inaccessible environments,but many markets expect the same level of functionality for long periods of time.Harsh environments cover areas that can be subjected to high temperature,(bio)-chemical and mechanical disturbances,electromagnetic noise,radiation,or high vacuum.In the field of actuators,the devices must maintain stringent accuracy specifications for displacement,force,and response times,among others.These new requirements present additional challenges in the compensation for or elimination of cross-sensitivities.Many state-of-the-art precision devices lose their precision and reliability when exposed to harsh environments.It is also important that advanced sensor and actuator systems maintain maximum autonomy such that the devices can operate independently with low maintenance.The next-generation microsystems will be deployed in remote and/or inaccessible and harsh environments that present many challenges to sensor design,materials,device functionality,and packaging.All of these aspects of integrated sensors and actuator microsystems require a multidisciplinary approach to overcome these challenges.The main areas of importance are in the fields of materials science,micro/nano-fabrication technology,device design,circuitry and systems,(first-level)packaging,and measurement strategy.This study examines the challenges presented by harsh environments and investigates the required approaches.Examples of successful devices are also given.
