Needs in scintimammography applications,especially for small animal cardiac imaging,lead to develop a small field of view,high spatial resolution gamma camera with a pinhole collimator.However the ideal pinhole collim...Needs in scintimammography applications,especially for small animal cardiac imaging,lead to develop a small field of view,high spatial resolution gamma camera with a pinhole collimator.However the ideal pinhole collimator must keep a compromise between spatial resolution and sensitivity.In order to design a pinhole collimator with an optimized sensitivity and spatial resolution,the spatial resolution and the geometric sensitivity response as a function of the source to collimator distance has been obtained by means of Monte-Carlo simulation for a small field of view gamma camera with a pinhole collimator of various-hole diameters.The results show that the camera with pinhole of 1 mm,1.5 mm and 2 mm diameter has respectively spatial resolution of 1.5 mm,2.25 mm and 3 mm and geometric sensitivity of 0.016%,0.022%and 0.036%,while the source to collimator distance is 3 cm.We chose the pinhole collimator with hole diameter size of 1.2 mm for our the gamma camera designed based on the trade-off between sensitivity and resolution.展开更多
High resolution remote sensing data has been applied in many fields such as national security, economic construction and in the daily life of the general public around the world, creating a huge market. Commercial rem...High resolution remote sensing data has been applied in many fields such as national security, economic construction and in the daily life of the general public around the world, creating a huge market. Commercial remote sensing cameras have been developed vigorously throughout the world over the last few decades, resulting in resolutions down to 0.31 m. In 2010, the Chinese government approved the implementation of the China High-resolution Earth Observation System(CHEOS) Major Special Project, giving priority to development of high resolution remote sensing satellites. More than half of CHEOS has been constructed to date and 5 satellites operate in orbit. These cameras have different characteristics. A number of innovative technologies have been adopted, which have led to camera performance increasing in leaps and bounds. The products and the production capability enables the remote sensing technical level to increase making it on a par with Europe and the US.展开更多
Compound eyes found in insects provide intriguing sources of biological inspiration for miniaturised imaging systems.Here,we report an ultrathin arrayed camera inspired by insect eye structures for high-contrast and s...Compound eyes found in insects provide intriguing sources of biological inspiration for miniaturised imaging systems.Here,we report an ultrathin arrayed camera inspired by insect eye structures for high-contrast and super-resolution imaging.The ultrathin camera features micro-optical elements(MOEs),i.e.,inverted microlenses,multilayered pinhole arrays,and gap spacers on an image sensor.The MOE was fabricated by using repeated photolithography and thermal reflow.The fully packaged camera shows a total track length of 740μm and a field-of-view(FOV)of 73°.The experimental results demonstrate that the multilayered pinhole of the MOE allows high-contrast imaging by eliminating the optical crosstalk between microlenses.The integral image reconstructed from array images clearly increases the modulation transfer function(MTF)by~1.57 times compared to that of a single channel image in the ultrathin camera.This ultrathin arrayed camera provides a novel and practical direction for diverse mobile,surveillance or medical applications.展开更多
基金Supported by National Foundation of Nature Science of China(No.10275063)
文摘Needs in scintimammography applications,especially for small animal cardiac imaging,lead to develop a small field of view,high spatial resolution gamma camera with a pinhole collimator.However the ideal pinhole collimator must keep a compromise between spatial resolution and sensitivity.In order to design a pinhole collimator with an optimized sensitivity and spatial resolution,the spatial resolution and the geometric sensitivity response as a function of the source to collimator distance has been obtained by means of Monte-Carlo simulation for a small field of view gamma camera with a pinhole collimator of various-hole diameters.The results show that the camera with pinhole of 1 mm,1.5 mm and 2 mm diameter has respectively spatial resolution of 1.5 mm,2.25 mm and 3 mm and geometric sensitivity of 0.016%,0.022%and 0.036%,while the source to collimator distance is 3 cm.We chose the pinhole collimator with hole diameter size of 1.2 mm for our the gamma camera designed based on the trade-off between sensitivity and resolution.
文摘High resolution remote sensing data has been applied in many fields such as national security, economic construction and in the daily life of the general public around the world, creating a huge market. Commercial remote sensing cameras have been developed vigorously throughout the world over the last few decades, resulting in resolutions down to 0.31 m. In 2010, the Chinese government approved the implementation of the China High-resolution Earth Observation System(CHEOS) Major Special Project, giving priority to development of high resolution remote sensing satellites. More than half of CHEOS has been constructed to date and 5 satellites operate in orbit. These cameras have different characteristics. A number of innovative technologies have been adopted, which have led to camera performance increasing in leaps and bounds. The products and the production capability enables the remote sensing technical level to increase making it on a par with Europe and the US.
基金financially supported by a grant from the National Research Foundation of Korea(NRF)(No.2019023700)Ministry of Health&Welfare,Republic of Korea(No.HI16C1111).
文摘Compound eyes found in insects provide intriguing sources of biological inspiration for miniaturised imaging systems.Here,we report an ultrathin arrayed camera inspired by insect eye structures for high-contrast and super-resolution imaging.The ultrathin camera features micro-optical elements(MOEs),i.e.,inverted microlenses,multilayered pinhole arrays,and gap spacers on an image sensor.The MOE was fabricated by using repeated photolithography and thermal reflow.The fully packaged camera shows a total track length of 740μm and a field-of-view(FOV)of 73°.The experimental results demonstrate that the multilayered pinhole of the MOE allows high-contrast imaging by eliminating the optical crosstalk between microlenses.The integral image reconstructed from array images clearly increases the modulation transfer function(MTF)by~1.57 times compared to that of a single channel image in the ultrathin camera.This ultrathin arrayed camera provides a novel and practical direction for diverse mobile,surveillance or medical applications.