Continuing advancement in astronomy,space exploration,and scientific detection,has increased demand for infrared multi-band detection systems.Traditional three-band optical systems,designed to simultaneously image at ...Continuing advancement in astronomy,space exploration,and scientific detection,has increased demand for infrared multi-band detection systems.Traditional three-band optical systems,designed to simultaneously image at infrared short-wave,mid-wave,and long-wave bands typically rely on dispersive elements,leading to bulky sizes,complex system architectures,low efficiency,and challenges in rapid assembly.To overcome these obstacles,in combination with the latest third-generation infrared detectors,we propose a design for a compact and lightweight three-band optical system,with infrared capabilities in all three required bands.The core of this approach is an integrated design philosophy that emphasizes the high steepness of mirror surfaces.This design achieves uniform correction and optimization of chromatic aberration and off-axis aberration across the spectral range.We introduce a novel integration of optical and mechanical elements to replace traditional assembly,reducing manufacturing and assembly errors,and degrees of freedom,associated with high-power optical elements.Confirming the effectiveness through a combination of simulations and experimental comparisons,the measured mid-wave full-field transfer function exceeds 0.405 at 17 lp/mm,satisfying the imaging requirements of the system.The optical system is lightweight and compact,with a total mass under 408 g and a compact volume of justΦ112 mm×117 mm.This serves as a valuable reference for the engineering application of high-performance,compact multi-band infrared composite detection systems for astronomy and space exploration.展开更多
Dear Editor,It is now well established that optogenetic stimulation can achieve precise intervention and modulate the activity of local neurons or neural circuits in the brain.Although this technique holds promise for...Dear Editor,It is now well established that optogenetic stimulation can achieve precise intervention and modulate the activity of local neurons or neural circuits in the brain.Although this technique holds promise for clinical therapy for neurological and psychiatric disorders,it requires the expression of lightsensitive proteins(such as channel rhodopsin)or photoactivatable chemicals(such as caged neurotransmitters)in the targeted brain regions[1].展开更多
The weak interlayer van der Waals(vdW) interactions in two-dimensional(2D) vdW materials enable sliding ferroelectricity as an effective strategy for modulating their intrinsic properties. In this work, we systematica...The weak interlayer van der Waals(vdW) interactions in two-dimensional(2D) vdW materials enable sliding ferroelectricity as an effective strategy for modulating their intrinsic properties. In this work, we systematically investigate the influence of interlayer sliding on the electronic behavior of PtSe_(2) using density functional theory(DFT) calculations. Our results demonstrate that interlayer sliding induces a pronounced photocurrent spanning the short-wavelength infrared to visible spectral ranges. Remarkably, under an applied gate voltage, the sliding ferroelectric PtSe_(2) exhibits anomalously enhanced photovoltaic performance and an ultrahigh extinction ratio.Transmission spectral analysis reveals that this phenomenon originates from band structure modifications driven by energy-level transitions. Furthermore, the observed photocurrent enhancement via sliding ferroelectricity demonstrates universality across diverse platinum-based optoelectronic devices. This study introduces a novel paradigm for tailoring the intrinsic characteristics of 2D vdW semiconductors, expanding the design space for next-generation ferroelectric materials in advanced optoelectronic applications.展开更多
Dynamic infrared scene simulation is for discovering and solving the problems encountered in designing, developing and manufacturing infrared imaging guidance weapons. The infrared scene simulation is explored by usin...Dynamic infrared scene simulation is for discovering and solving the problems encountered in designing, developing and manufacturing infrared imaging guidance weapons. The infrared scene simulation is explored by using the digital grayscale modulation method. The infrared image modulation model of a digital micro-mirror device (DMD) is established and then the infrared scene simulator prototype which is based on DMD grayscale modulation is developed. To evaluate its main parameters such as resolution, contrast, minimum temperature difference, gray scale, various DMD subsystems such as signal decoding, image normalization, synchronization drive, pulse width modulation (PWM) and DMD chips are designed. The infrared scene simulator is tested on a certain infrared missile seeker. The test results show preliminarily that the infrared scene simulator has high gray scale, small geometrical distortion and highly resolvable imaging resolution and contrast and yields high-fidelity images, thus being able to meet the requirements for the infrared scene simulation inside a laboratory.展开更多
The multiple input multiple output(MIMO) systems using serial infrared(SIR),return to zero-inverted(RZI) and on off keying(OOK) modulation were studied. Also, by analyzing experimental results, curve fitting models we...The multiple input multiple output(MIMO) systems using serial infrared(SIR),return to zero-inverted(RZI) and on off keying(OOK) modulation were studied. Also, by analyzing experimental results, curve fitting models were established. Three infrared MIMO systems with 2X2, 2X4 and 4X4 MIMO channels using RZI and OOK modulation were designed and tested. Based on the experimental results, evaluations between BER, distance and displacement were discussed.展开更多
A compact prototype based on mid-infrared wavelength modulation spectroscopy(WMS)is developed for the simul-taneous monitoring of NO,NO2,and NH3 in the urban area.Three quantum cascade lasers(QCLs)with central fre...A compact prototype based on mid-infrared wavelength modulation spectroscopy(WMS)is developed for the simul-taneous monitoring of NO,NO2,and NH3 in the urban area.Three quantum cascade lasers(QCLs)with central frequencies around 1900.0 cm^-1,1600.0 cm^-1,and 1103.4 cm^-1are used for NO,NO2,and NH3detections,respectively,by timedivision multiplex.An open-path multi-pass cell of 60-m optical path length is applied to the instrument for high sensitivity and reducing the response time to less than 1 s.The prototype achieves a sub-ppb detection limit for all the three target gases with an average time of about 100 s.The instrument is installed in the Jiangsu environmental monitoring center to conduct performance tests on ambient air.Continuous 24-hour measurements show good agreement with the results of a reference instrument based on the chemiluminescence technique.展开更多
A 3D temperature field distribution of biological tissue for superficial hyperthermia using a pulse modulated microwave (PMMW) was presented. A 3D sliced homogeneous phantom was radiated by the PMMW and an infrared ...A 3D temperature field distribution of biological tissue for superficial hyperthermia using a pulse modulated microwave (PMMW) was presented. A 3D sliced homogeneous phantom was radiated by the PMMW and an infrared thermal imager was applied to image temperature distribution throughout the phantom. The period of the PMMW is 3 s and the output power is 35 W. The temperature rises by at least 3 ℃ in the phantom when the duty cycle varies from 1/3, 1/2, 2/3 to 1 (denoted by scenarios 1-4). Both the accumulative temperature-volume histogram and the relative depth-area ratio histogram show that the maximum temperature rise (MTR) is 6.6 and 8 ℃ in scenarios 2 and 3, and they are superior to scenarios 1 and 4. Furthermore, the PMMW can control temperature field distribution of biological tissue. It provides both preliminary basis for thermal volume control and new technology for temperature control and monitor in superficial hyperthermia.展开更多
Infrared target detection models are more required than ever before to be deployed on embedded platforms,which requires models with less memory consumption and better real-time performance while considering accuracy.T...Infrared target detection models are more required than ever before to be deployed on embedded platforms,which requires models with less memory consumption and better real-time performance while considering accuracy.To address the above challenges,we propose a modified You Only Look Once(YOLO)algorithm PF-YOLOv4-Tiny.The algorithm incorpo-rates spatial pyramidal pooling(SPP)and squeeze-and-excitation(SE)visual attention modules to enhance the target localization capability.The PANet-based-feature pyramid networks(P-FPN)are proposed to transfer semantic information and location information simultaneously to ameliorate detection accuracy.To lighten the network,the standard convolutions other than the backbone network are replaced with depthwise separable convolutions.In post-processing the images,the soft-non-maximum suppression(soft-NMS)algorithm is employed to subside the missed and false detection problems caused by the occlusion between targets.The accuracy of our model can finally reach 61.75%,while the total Params is only 9.3 M and GFLOPs is 11.At the same time,the inference speed reaches 87 FPS on NVIDIA GeForce GTX 1650 Ti,which can meet the requirements of the infrared target detection algorithm for the embedded deployments.展开更多
High-power intense optical sources in the mid-to-long wavelength infrared region are very attractive for a wide range of fields from fundamental research to materials science and biology applications.However,there are...High-power intense optical sources in the mid-to-long wavelength infrared region are very attractive for a wide range of fields from fundamental research to materials science and biology applications.However,there are still significant challenges in extending long-wavelength infrared pulses into the relativistic regime using conventional optical techniques.Here,based upon a new type of plasma-based optical method,we present an efficient scheme capable of combining several high-power long-wavelength infrared laser pulses into one single,more intense pulse,thus bringing the intensity of the output pulse to the relativistic regime.Such intense infrared pulses will open up new possibilities for strong-field physics and ultrafast applications.Furthermore,this is beneficial to understand the underlying physics and nonlinear processes of modulation,propagation and energy transfer of high-power intense laser pulses in plasmas.展开更多
In this paper, The principle, structure and practical application of a novel multiple component gas infrared ray sensor are discussed. The optical gas sensor, which has infrared radiation impulses input and electric s...In this paper, The principle, structure and practical application of a novel multiple component gas infrared ray sensor are discussed. The optical gas sensor, which has infrared radiation impulses input and electric single output, is composed of narrow band light filter, optical taper and pyroelectric detector array. An infrared gas analyzer with multiple component gas tested synchronously consists of the sensor, single middle infrared source, single gas cell and computer data acquire system. As compared with sensor in other infrared gas analyzer, it has many merits such as novel structure, strong anti\|oscillate performance and low cost. Different gas in different measurement area can be analyzed quantitatively by replacing optical filter module easily.展开更多
We propose a new optical probe for near-infrared (NIR) fluorescence signal detection with high optical performance and thermal stability. The optical probe is composed of an optical source part for efficient excitatio...We propose a new optical probe for near-infrared (NIR) fluorescence signal detection with high optical performance and thermal stability. The optical probe is composed of an optical source part for efficient excitation of NIR fluorescence signal, a heat dissipation part for stable operation of the NIR fluorescence probe, and an optical detection part for efficient detection of NIR fluorescence signal. From a simulation by use of an optical simulation tool, Light ToolsTM, we could confirm that the optical probe has optical propagation efficiency of 79.6% in case of using a circular detector with 20 cm in diameter located at 20 cm in distance from the optical source. From a measurement of temperature variation of the optical probe, we could also confirm that the optical probe has thermal stability with a standard deviation of 2.19°C under room temperature condition. Finally, from an evaluation of fluorescence image quality, we could confirm that an optical noise which can bring on by overlapped band between optical spectrum of the optical source for fluorescence excitation and optical spectrum of the emitted fluorescence signal decreased effectively in the optical probe.展开更多
调制传递函数是红外遥感卫星像质评价的核心参数,但其在轨检测面临靶标温差稳定性不足与数据处理复杂两大挑战。提出一种基于三线靶标与温阶靶标协同的在轨调制传递函数(modulation transfer function,MTF)直接检测方法,通过靶标设计与...调制传递函数是红外遥感卫星像质评价的核心参数,但其在轨检测面临靶标温差稳定性不足与数据处理复杂两大挑战。提出一种基于三线靶标与温阶靶标协同的在轨调制传递函数(modulation transfer function,MTF)直接检测方法,通过靶标设计与模糊PID(proportional-integralderivative)温控算法,实现靶标温度均匀性(<0.5℃)、稳定性(±0.6℃)与重复性(>99%)的良好表现。基于傅里叶光学理论与辐射传输模型,结合“物方-像方调制度分离”计算原理,从遥感影像中直接提取奈奎斯特频率处MTF值,避免了传统方法中大气因素、数值微分以及参数拟合误差等对MTF检测的影响,为高分辨率红外卫星定量化应用提供了高精度技术支撑。展开更多
基金National Natural Science Foundation of China(12073028,12473084).
文摘Continuing advancement in astronomy,space exploration,and scientific detection,has increased demand for infrared multi-band detection systems.Traditional three-band optical systems,designed to simultaneously image at infrared short-wave,mid-wave,and long-wave bands typically rely on dispersive elements,leading to bulky sizes,complex system architectures,low efficiency,and challenges in rapid assembly.To overcome these obstacles,in combination with the latest third-generation infrared detectors,we propose a design for a compact and lightweight three-band optical system,with infrared capabilities in all three required bands.The core of this approach is an integrated design philosophy that emphasizes the high steepness of mirror surfaces.This design achieves uniform correction and optimization of chromatic aberration and off-axis aberration across the spectral range.We introduce a novel integration of optical and mechanical elements to replace traditional assembly,reducing manufacturing and assembly errors,and degrees of freedom,associated with high-power optical elements.Confirming the effectiveness through a combination of simulations and experimental comparisons,the measured mid-wave full-field transfer function exceeds 0.405 at 17 lp/mm,satisfying the imaging requirements of the system.The optical system is lightweight and compact,with a total mass under 408 g and a compact volume of justΦ112 mm×117 mm.This serves as a valuable reference for the engineering application of high-performance,compact multi-band infrared composite detection systems for astronomy and space exploration.
基金supported by grants from the Key Strategic Science and Technology Cooperation Project of the Ministry of Science and Technology of China(2023YFE0206800)the National Natural Science Foundation of China(81625006,31820103005,32200620,32170976,81971874)+1 种基金Zhejiang Province Natural Science Foundation of China(LZ24C090003 and LY21C090003)the Peak Discipline Cultivation Program of Zhejiang University School of Basic Medicine.
文摘Dear Editor,It is now well established that optogenetic stimulation can achieve precise intervention and modulate the activity of local neurons or neural circuits in the brain.Although this technique holds promise for clinical therapy for neurological and psychiatric disorders,it requires the expression of lightsensitive proteins(such as channel rhodopsin)or photoactivatable chemicals(such as caged neurotransmitters)in the targeted brain regions[1].
基金supported by the National Key Research and Development Program of China (Grant No. 2024YFB3211701)the National Natural Science Foundation of China (Grant Nos. T2222011, 62174026, and 12274234)+1 种基金the National Key Research and Development Program of China (Grant Nos. 2023YFB3611400 and 2019YFA0308000)the Fundamental Research Funds for the Central Universities (Grant No. 242023k30027)。
文摘The weak interlayer van der Waals(vdW) interactions in two-dimensional(2D) vdW materials enable sliding ferroelectricity as an effective strategy for modulating their intrinsic properties. In this work, we systematically investigate the influence of interlayer sliding on the electronic behavior of PtSe_(2) using density functional theory(DFT) calculations. Our results demonstrate that interlayer sliding induces a pronounced photocurrent spanning the short-wavelength infrared to visible spectral ranges. Remarkably, under an applied gate voltage, the sliding ferroelectric PtSe_(2) exhibits anomalously enhanced photovoltaic performance and an ultrahigh extinction ratio.Transmission spectral analysis reveals that this phenomenon originates from band structure modifications driven by energy-level transitions. Furthermore, the observed photocurrent enhancement via sliding ferroelectricity demonstrates universality across diverse platinum-based optoelectronic devices. This study introduces a novel paradigm for tailoring the intrinsic characteristics of 2D vdW semiconductors, expanding the design space for next-generation ferroelectric materials in advanced optoelectronic applications.
基金co-supported by China Postdoctoral Science Foundation (20090461314)
文摘Dynamic infrared scene simulation is for discovering and solving the problems encountered in designing, developing and manufacturing infrared imaging guidance weapons. The infrared scene simulation is explored by using the digital grayscale modulation method. The infrared image modulation model of a digital micro-mirror device (DMD) is established and then the infrared scene simulator prototype which is based on DMD grayscale modulation is developed. To evaluate its main parameters such as resolution, contrast, minimum temperature difference, gray scale, various DMD subsystems such as signal decoding, image normalization, synchronization drive, pulse width modulation (PWM) and DMD chips are designed. The infrared scene simulator is tested on a certain infrared missile seeker. The test results show preliminarily that the infrared scene simulator has high gray scale, small geometrical distortion and highly resolvable imaging resolution and contrast and yields high-fidelity images, thus being able to meet the requirements for the infrared scene simulation inside a laboratory.
基金Supported by the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDA17040401)
文摘The multiple input multiple output(MIMO) systems using serial infrared(SIR),return to zero-inverted(RZI) and on off keying(OOK) modulation were studied. Also, by analyzing experimental results, curve fitting models were established. Three infrared MIMO systems with 2X2, 2X4 and 4X4 MIMO channels using RZI and OOK modulation were designed and tested. Based on the experimental results, evaluations between BER, distance and displacement were discussed.
基金Project supported by the National Key Scientific Instrument and Equipment Development,China(Grant No.2014YQ060537)the National Key Research and Development Program,China(Grant No.2016YFC0201103)
文摘A compact prototype based on mid-infrared wavelength modulation spectroscopy(WMS)is developed for the simul-taneous monitoring of NO,NO2,and NH3 in the urban area.Three quantum cascade lasers(QCLs)with central frequencies around 1900.0 cm^-1,1600.0 cm^-1,and 1103.4 cm^-1are used for NO,NO2,and NH3detections,respectively,by timedivision multiplex.An open-path multi-pass cell of 60-m optical path length is applied to the instrument for high sensitivity and reducing the response time to less than 1 s.The prototype achieves a sub-ppb detection limit for all the three target gases with an average time of about 100 s.The instrument is installed in the Jiangsu environmental monitoring center to conduct performance tests on ambient air.Continuous 24-hour measurements show good agreement with the results of a reference instrument based on the chemiluminescence technique.
基金Project(50977064) supported by the National Natural Science Foundation of China
文摘A 3D temperature field distribution of biological tissue for superficial hyperthermia using a pulse modulated microwave (PMMW) was presented. A 3D sliced homogeneous phantom was radiated by the PMMW and an infrared thermal imager was applied to image temperature distribution throughout the phantom. The period of the PMMW is 3 s and the output power is 35 W. The temperature rises by at least 3 ℃ in the phantom when the duty cycle varies from 1/3, 1/2, 2/3 to 1 (denoted by scenarios 1-4). Both the accumulative temperature-volume histogram and the relative depth-area ratio histogram show that the maximum temperature rise (MTR) is 6.6 and 8 ℃ in scenarios 2 and 3, and they are superior to scenarios 1 and 4. Furthermore, the PMMW can control temperature field distribution of biological tissue. It provides both preliminary basis for thermal volume control and new technology for temperature control and monitor in superficial hyperthermia.
基金supported by The Natural Science Foundation of the Jiangsu Higher Education Institutions of China(Grants No.19JKB520031).
文摘Infrared target detection models are more required than ever before to be deployed on embedded platforms,which requires models with less memory consumption and better real-time performance while considering accuracy.To address the above challenges,we propose a modified You Only Look Once(YOLO)algorithm PF-YOLOv4-Tiny.The algorithm incorpo-rates spatial pyramidal pooling(SPP)and squeeze-and-excitation(SE)visual attention modules to enhance the target localization capability.The PANet-based-feature pyramid networks(P-FPN)are proposed to transfer semantic information and location information simultaneously to ameliorate detection accuracy.To lighten the network,the standard convolutions other than the backbone network are replaced with depthwise separable convolutions.In post-processing the images,the soft-non-maximum suppression(soft-NMS)algorithm is employed to subside the missed and false detection problems caused by the occlusion between targets.The accuracy of our model can finally reach 61.75%,while the total Params is only 9.3 M and GFLOPs is 11.At the same time,the inference speed reaches 87 FPS on NVIDIA GeForce GTX 1650 Ti,which can meet the requirements of the infrared target detection algorithm for the embedded deployments.
基金the National Postdoctoral Program for Innovative Talents of China(No.BX20220206)。
文摘High-power intense optical sources in the mid-to-long wavelength infrared region are very attractive for a wide range of fields from fundamental research to materials science and biology applications.However,there are still significant challenges in extending long-wavelength infrared pulses into the relativistic regime using conventional optical techniques.Here,based upon a new type of plasma-based optical method,we present an efficient scheme capable of combining several high-power long-wavelength infrared laser pulses into one single,more intense pulse,thus bringing the intensity of the output pulse to the relativistic regime.Such intense infrared pulses will open up new possibilities for strong-field physics and ultrafast applications.Furthermore,this is beneficial to understand the underlying physics and nonlinear processes of modulation,propagation and energy transfer of high-power intense laser pulses in plasmas.
文摘In this paper, The principle, structure and practical application of a novel multiple component gas infrared ray sensor are discussed. The optical gas sensor, which has infrared radiation impulses input and electric single output, is composed of narrow band light filter, optical taper and pyroelectric detector array. An infrared gas analyzer with multiple component gas tested synchronously consists of the sensor, single middle infrared source, single gas cell and computer data acquire system. As compared with sensor in other infrared gas analyzer, it has many merits such as novel structure, strong anti\|oscillate performance and low cost. Different gas in different measurement area can be analyzed quantitatively by replacing optical filter module easily.
文摘We propose a new optical probe for near-infrared (NIR) fluorescence signal detection with high optical performance and thermal stability. The optical probe is composed of an optical source part for efficient excitation of NIR fluorescence signal, a heat dissipation part for stable operation of the NIR fluorescence probe, and an optical detection part for efficient detection of NIR fluorescence signal. From a simulation by use of an optical simulation tool, Light ToolsTM, we could confirm that the optical probe has optical propagation efficiency of 79.6% in case of using a circular detector with 20 cm in diameter located at 20 cm in distance from the optical source. From a measurement of temperature variation of the optical probe, we could also confirm that the optical probe has thermal stability with a standard deviation of 2.19°C under room temperature condition. Finally, from an evaluation of fluorescence image quality, we could confirm that an optical noise which can bring on by overlapped band between optical spectrum of the optical source for fluorescence excitation and optical spectrum of the emitted fluorescence signal decreased effectively in the optical probe.
文摘调制传递函数是红外遥感卫星像质评价的核心参数,但其在轨检测面临靶标温差稳定性不足与数据处理复杂两大挑战。提出一种基于三线靶标与温阶靶标协同的在轨调制传递函数(modulation transfer function,MTF)直接检测方法,通过靶标设计与模糊PID(proportional-integralderivative)温控算法,实现靶标温度均匀性(<0.5℃)、稳定性(±0.6℃)与重复性(>99%)的良好表现。基于傅里叶光学理论与辐射传输模型,结合“物方-像方调制度分离”计算原理,从遥感影像中直接提取奈奎斯特频率处MTF值,避免了传统方法中大气因素、数值微分以及参数拟合误差等对MTF检测的影响,为高分辨率红外卫星定量化应用提供了高精度技术支撑。