Thrombus formation in the artificial heart blood pump is a complex problem. The most important factor of thrombosis in the blood pump is the quality of blood contacting surface which is related to hemocompatibility of...Thrombus formation in the artificial heart blood pump is a complex problem. The most important factor of thrombosis in the blood pump is the quality of blood contacting surface which is related to hemocompatibility of materials and micromorphololgy or roughness of the surface. So it is necessary to understand the morphology of the surface inside of blood pump in order to develop and improve a good quality blood pump. The authors observed and analysed the inner surface of blood pumps (both preimplanted and postimplanted) with scanning electron microscopy (SEM) providing a means for evaluating the blood pumps and for developing good quality of blood pumps. It was observed that there were four kinds of surface defects on the inner surface of the blood pumps: air bubble domes, open bubble craters, contaminated dust and gel particles. Microcrakes had also been found on the diaphragm of the postimplanted pump. But in the newly improved blood pump that had been imlanted for 16 days, there were few defects on the blood contacting surface, and only a little fibrinous layer observed. It could be considered that the current design and modifications are reasonable. Since some problems associated with the surface defects and thrombosis still existed, further improvement in fabrication process and quality control procedures with SEM are under way.展开更多
Phase is one of the most important parameters of electromagnetic waves. It is the phase distribution that determines the propagation, reflection, refraction, focusing, divergence, and coupling features of light, and f...Phase is one of the most important parameters of electromagnetic waves. It is the phase distribution that determines the propagation, reflection, refraction, focusing, divergence, and coupling features of light, and further affects the intensity distribution. In recent years, the designs of surface plasmon polariton （SPP） devices have mostly been based on the phase modulation and manipulation. Here we demonstrate a phase sensitive multi-parameter heterodyne scanning near-field opti- cal microscope （SNOM） with an aperture probe in the visible range, with which the near field optical phase and amplitude distributions can be simultaneously obtained. A novel architecture combining a spatial optical path and a fiber optical path is employed for stability and flexibility. Two kinds of typical nano-photonic devices are tested with the system. With the phase-sensitive SNOM, the phase and amplitude distributions of any nano-optical field and localized field generated with any SPP nano-structures and irregular phase modulation surfaces can be investigated. The phase distribution and the interference pattern will help us to gain a better understanding of how light interacts with SPP structures and how SPP waves generate, localize, convert, and propagate on an SPP surface. This will be a significant guidance on SPP nano-structure design and optimization.展开更多
This paper analyzes the operation parameters of the time delay and integration (TDI) line scan CCD camera, such as resolution, line rate, clock frequency, etc. and their mathematical relationship is deduced. By analyz...This paper analyzes the operation parameters of the time delay and integration (TDI) line scan CCD camera, such as resolution, line rate, clock frequency, etc. and their mathematical relationship is deduced. By analyzing and calculating these parameters, the working clocks of the TDI CCD line scan camera are designed, which guarantees the synchronization of the line scan rate and the camera movement speed. The IL-E2 TDI CCD of DALSA Co. is used as the sensor of the camera in the paper. The working clock generator used for the TDI CCD sensor is realized by using the programmable logic device (PLD). The experimental results show that the working clock generator circuit satisfies the requirement of high speed TDI CCD line scan camera.展开更多
Image scanning microscopy(ISM)is a promising imaging technique that offers sub-diffraction-limited resolution and optical sectioning.Theoretically,ISM can improve the optical resolution by a factor of two through pixe...Image scanning microscopy(ISM)is a promising imaging technique that offers sub-diffraction-limited resolution and optical sectioning.Theoretically,ISM can improve the optical resolution by a factor of two through pixel reassignment and deconvolution.Multifocal array illumination and scanning have been widely adopted to implement ISM because of their simplicity.Conventionally,digital micromirror devices(DMDs)1 and microlens arrays(MLAs)2,3 have been used to generate dense and uniform multifocal arrays for ISM,which are critical for achieving fast imaging and high-quality ISM reconstruction.However,these approaches have limitations in terms of cost,numerical aperture(NA),pitch,and uniformity,making it challenging to create dense and high-quality multifocal arrays at high NA.To overcome these limitations,we introduced a novel multifocal metalens design strategy called the hybrid multiplexing method,which combines two conventional multiplexing approaches:phase addition and random multiplexing.Through numerical simulations,we demonstrate that the proposed method generates more uniform and denser multifocal arrays than conventional methods,even at small pitches.As a proof of concept,we fabricated a multifocal metalens generating 40×40 array of foci with a 3μm pitch and NA of 0.7 operating at a wavelength of 488 nm and then constructed the multifocal metalens-based ISM(MMISM).We demonstrated that MMISM successfully resolved sub-diffraction-limited features in imaging of microbead samples and forebrain organoid sections.The results showed that MMISM imaging achieved twice the diffraction-limited resolution and revealed clearer structural features of neurons compared to wide-field images.We anticipate that our novel design strategy can be widely applied to produce multifunctional optical elements and replace conventional optical elements in specialized applications.展开更多
文摘Thrombus formation in the artificial heart blood pump is a complex problem. The most important factor of thrombosis in the blood pump is the quality of blood contacting surface which is related to hemocompatibility of materials and micromorphololgy or roughness of the surface. So it is necessary to understand the morphology of the surface inside of blood pump in order to develop and improve a good quality blood pump. The authors observed and analysed the inner surface of blood pumps (both preimplanted and postimplanted) with scanning electron microscopy (SEM) providing a means for evaluating the blood pumps and for developing good quality of blood pumps. It was observed that there were four kinds of surface defects on the inner surface of the blood pumps: air bubble domes, open bubble craters, contaminated dust and gel particles. Microcrakes had also been found on the diaphragm of the postimplanted pump. But in the newly improved blood pump that had been imlanted for 16 days, there were few defects on the blood contacting surface, and only a little fibrinous layer observed. It could be considered that the current design and modifications are reasonable. Since some problems associated with the surface defects and thrombosis still existed, further improvement in fabrication process and quality control procedures with SEM are under way.
基金supported by the National Natural Science Foundation of China(Grant Nos.61177089,61227014,and 60978047)
文摘Phase is one of the most important parameters of electromagnetic waves. It is the phase distribution that determines the propagation, reflection, refraction, focusing, divergence, and coupling features of light, and further affects the intensity distribution. In recent years, the designs of surface plasmon polariton （SPP） devices have mostly been based on the phase modulation and manipulation. Here we demonstrate a phase sensitive multi-parameter heterodyne scanning near-field opti- cal microscope （SNOM） with an aperture probe in the visible range, with which the near field optical phase and amplitude distributions can be simultaneously obtained. A novel architecture combining a spatial optical path and a fiber optical path is employed for stability and flexibility. Two kinds of typical nano-photonic devices are tested with the system. With the phase-sensitive SNOM, the phase and amplitude distributions of any nano-optical field and localized field generated with any SPP nano-structures and irregular phase modulation surfaces can be investigated. The phase distribution and the interference pattern will help us to gain a better understanding of how light interacts with SPP structures and how SPP waves generate, localize, convert, and propagate on an SPP surface. This will be a significant guidance on SPP nano-structure design and optimization.
基金Sponsored by the Research Fund of Harbin Institute of Technology (Grant No.HITMD 2001.18).
文摘This paper analyzes the operation parameters of the time delay and integration (TDI) line scan CCD camera, such as resolution, line rate, clock frequency, etc. and their mathematical relationship is deduced. By analyzing and calculating these parameters, the working clocks of the TDI CCD line scan camera are designed, which guarantees the synchronization of the line scan rate and the camera movement speed. The IL-E2 TDI CCD of DALSA Co. is used as the sensor of the camera in the paper. The working clock generator used for the TDI CCD sensor is realized by using the programmable logic device (PLD). The experimental results show that the working clock generator circuit satisfies the requirement of high speed TDI CCD line scan camera.
基金supported by the Samsung Research Funding&Incubation Center of Samsung Electronics under Project Number SRFC-IT2401-01 and by National Research Foundation(NRF)grants(RS-2024-00462912,RS-2023-00266110,and RS-2020-NR049544)funded by the Ministry of Science and ICT(MSIT)of the Korean governmentI.K.acknowledges the NRF Sejong Science Fellowship(RS-2021-NR061797)funded by the MSIT of the Korean government.We would like to express our sincere gratitude to Yangkyu Kim for his invaluable assistance in correcting the mathematical errors in this paper.
文摘Image scanning microscopy(ISM)is a promising imaging technique that offers sub-diffraction-limited resolution and optical sectioning.Theoretically,ISM can improve the optical resolution by a factor of two through pixel reassignment and deconvolution.Multifocal array illumination and scanning have been widely adopted to implement ISM because of their simplicity.Conventionally,digital micromirror devices(DMDs)1 and microlens arrays(MLAs)2,3 have been used to generate dense and uniform multifocal arrays for ISM,which are critical for achieving fast imaging and high-quality ISM reconstruction.However,these approaches have limitations in terms of cost,numerical aperture(NA),pitch,and uniformity,making it challenging to create dense and high-quality multifocal arrays at high NA.To overcome these limitations,we introduced a novel multifocal metalens design strategy called the hybrid multiplexing method,which combines two conventional multiplexing approaches:phase addition and random multiplexing.Through numerical simulations,we demonstrate that the proposed method generates more uniform and denser multifocal arrays than conventional methods,even at small pitches.As a proof of concept,we fabricated a multifocal metalens generating 40×40 array of foci with a 3μm pitch and NA of 0.7 operating at a wavelength of 488 nm and then constructed the multifocal metalens-based ISM(MMISM).We demonstrated that MMISM successfully resolved sub-diffraction-limited features in imaging of microbead samples and forebrain organoid sections.The results showed that MMISM imaging achieved twice the diffraction-limited resolution and revealed clearer structural features of neurons compared to wide-field images.We anticipate that our novel design strategy can be widely applied to produce multifunctional optical elements and replace conventional optical elements in specialized applications.
