Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,...Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,a femtosecond laser Bessel beam is proposed to process micro-FZP,which is modulated from a Gaussian beam to a Bessel annular beam.The processing time for FZP with an outer diameter of 60μm is reduced from 30 min to 1.5 min on an important semiconductor material gallium arsenide(GaAs),which significantly improves the processing efficiency.In the modulation process,a central ablation hole that has an adverse effect on the diffraction performance is produced,and the adverse effect is eliminated by superimposing the blazed grating hologram.Meanwhile,the FZP machined by spatial light modulator(SLM)has good morphology and higher diffraction efficiency,which provides a strong guarantee for the application of micro-FZP in computed tomography and solar photovoltaic cells.展开更多
The liquid crystal spatial light modulator （LC SLM） is very suitable for wavefront correction and optical testing and can produce a wavefront with large phase change and high accuracy. The LC SLM is composed of thou...The liquid crystal spatial light modulator （LC SLM） is very suitable for wavefront correction and optical testing and can produce a wavefront with large phase change and high accuracy. The LC SLM is composed of thousands of pixels and the pixel size and shape have effects on the diffractive characteristics of the LC SLM. This paper investigates the pixel effect on the phase of the wavefront with the scalar diffractive theory. The results show that the maximum optical path difference modulation is 41μm to produce the paraboloid wavefront with the peak to valley accuracy better than λ/10. Effects of the mismatch between the pixel and the period, and black matrix on the diffraction efficiency of the LC SLM are also analysed with the Fresnel phase lens model. The ability of the LC SLM is discussed for optical testing and wavefront correction based on the calculated results. It shows that the LC SLM can be used as a wavefront corrector and a compensator.展开更多
Spatial light modulators,as dynamic flat-panel optical devices,have witnessed rapid development over the past two decades,concomitant with the advancements in micro-and opto-electronic integration technology.In partic...Spatial light modulators,as dynamic flat-panel optical devices,have witnessed rapid development over the past two decades,concomitant with the advancements in micro-and opto-electronic integration technology.In particular,liquid-crystal spatial light modulator(LC-SLM)technologies have been regarded as versatile tools for generating arbitrary optical fields and tailoring all degrees of freedom beyond just phase and amplitude.These devices have gained significant interest in the nascent field of structured light in space and time,facilitated by their ease of use and real-time light manipulation,fueling both fundamental research and practical applications.Here we provide an overview of the key working principles of LC-SLMs and review the significant progress made to date in their deployment for various applications,covering topics as diverse as beam shaping and steering,holography,optical trapping and tweezers,measurement,wavefront coding,optical vortex,and quantum optics.Finally,we conclude with an outlook on the potential opportunities and technical challenges in this rapidly developing field.展开更多
We report three-dimensional fluorescence emission difference(3D-FED)microscopy using a spatial light modulator(SLM).Zero phase,0–2vortex phase and binary 0-pi phase are loaded on the SLM to generate the correspondin...We report three-dimensional fluorescence emission difference(3D-FED)microscopy using a spatial light modulator(SLM).Zero phase,0–2vortex phase and binary 0-pi phase are loaded on the SLM to generate the corresponding solid,doughnut and z-axis hollow excitation spot,respectively.Our technique achieves super-resolved image by subtracting three di®erently acquired images with proper subtractive factors.Detailed theoretical analysis and simulation tests are proceeded to testify the performance of 3D-FED.Also,the improvement of lateral and axial resolution is demonstrated by imaging 100 nm°uorescent beads.The experiment yields lateral resolution of 140 nm and axial resolution of approximate 380 nm.展开更多
Liquid crystal spatial light modulator （LCSLM） realizing equal-intensity multiple beams often has some features, i.e., phase valley between two adjacent pixels, flybaek region when phase decreases immediately from 2...Liquid crystal spatial light modulator （LCSLM） realizing equal-intensity multiple beams often has some features, i.e., phase valley between two adjacent pixels, flybaek region when phase decreases immediately from 2~r to 0, and inevitable backplane curvature, which are different from those of most conventional diffractive optical elements （DOEs）, such as static DOEs. For optimal intensity uniformity, equal-intensity multi-beam generation must be considered for these artifacts. We present a tunable-grating method in which the intensity uniformity can be improved by considering the LCSLM artifacts. For instance, tuning phase modulation depth of the grating, called isosceles triangle multilevel phase grating （ITMPG）, can be used not only to improve the intensity uniformity, but also to fast steer four beams with narrow beamwidths, determined by the same effective aperture of ITMPG. Improved intensity uniformity and high relative diffraction efficiency are demonstrated through experiments with phase-only LCSLM.展开更多
The extinction ratio and insertion loss of spatial light modulator are subject to the material problem, thus limiting its applications. One reflection-type silicon-based spatial light modulator with high reflective ma...The extinction ratio and insertion loss of spatial light modulator are subject to the material problem, thus limiting its applications. One reflection-type silicon-based spatial light modulator with high reflective materials outside the Fabry-Perot cavity is demonstrated in this paper. The reflectivity values of the outside-cavity materials with different film layer numbers are simulated. The reflectivity values of 6-pair Ta2O5/SiO2 films at 1550 nm are experimentally verified to be as high as 99.9%. The surfaces of 6-pair Ta2O5/SiO2 films are smooth: their root-mean-square roughness values are as small as 0.53 nm. The insertion loss of the device at 1550 nm is only 1.2 dB. The high extinction ratio of the device at 1550 nm and 11 V is achieved to be 29.7 dB. The spatial light modulator has a high extinction ratio and low insertion loss for applications.展开更多
Plasmonic modes within metal nanostructures play a pivotal role in various nanophotonic applications.However,a significant challenge arises from the fixed shapes of nanostructures post-fabrication,resulting in limited...Plasmonic modes within metal nanostructures play a pivotal role in various nanophotonic applications.However,a significant challenge arises from the fixed shapes of nanostructures post-fabrication,resulting in limited modes under ordinary illumination.A promising solution lies in far-field control facilitated by spatial light modulators(SLMs),which enable on-site,real-time,and non-destructive manipulation of plasmon excitation.Through the robust modulation of the incident light using SLMs,this approach enables the generation,optimization,and dynamic control of surface plasmon polariton(SPP)and localized surface plasmon(LSP)modes.The versatility of this technique introduces a rich array of tunable degrees of freedom to plasmon-enhanced spectroscopy,offering novel approaches for signal optimization and functional expansion in this field.This paper provides a comprehensive review of the generation and modulation of SPP and LSP modes through far-field control with SLMs and highlights the diverse applications of this optical technology in plasmon-enhanced spectroscopy.展开更多
The combined use of the photoelectric and electro-optic properties of BSO crystal (Bi 12 SiO 20 ) leads to realize spatial light modulation.Under some condition,BSO crystal can become birefringent depending on...The combined use of the photoelectric and electro-optic properties of BSO crystal (Bi 12 SiO 20 ) leads to realize spatial light modulation.Under some condition,BSO crystal can become birefringent depending on a local illuminance.The relationship between the distributions of an illuminance and a birefringence will be discussed.This spatial light modulator can work in real-time. The experiment shows,in order to increase the sensitivity of BSO crystal,an electric field of 6 kV/cm at an atmosphere pressure of 15×10 5 Pa should be applied to BSO crystal.With BSO we have measured 3-dimensional deformation by means of real-time holography.展开更多
The primary mirrors of current and future large telescopes always employ a segmented mirror configuration.The small but non-negligible gaps between neighboring segments cause additional diffraction,which restricts the...The primary mirrors of current and future large telescopes always employ a segmented mirror configuration.The small but non-negligible gaps between neighboring segments cause additional diffraction,which restricts the performance of high-contrast coronagraph.To solve this problem,we propose a coronagraph system based on a single liquid crystal spatial light modulator(SLM).This spatial light modulator is used for amplitude apodization,and its feasibility and potential performance are demonstrated using a laboratory setup using the stochastic parallel gradient descent(SPGD)algorithm to control the spatial light modulator,which is based on point spread function(PSF)sensing and evaluation and optimized for maximum contrast in the discovery working area as a merit function.The system delivers a contrast in the order of 10−6,and shows excellent potential to be used in current and future large aperture telescopes,both on the ground and in space.展开更多
This paper investigates the bit-interleaved coded generalized spatial modulation(BICGSM) with iterative decoding(BICGSM-ID) for multiple-input multiple-output(MIMO) visible light communications(VLC). In the BICGSM-ID ...This paper investigates the bit-interleaved coded generalized spatial modulation(BICGSM) with iterative decoding(BICGSM-ID) for multiple-input multiple-output(MIMO) visible light communications(VLC). In the BICGSM-ID scheme, the information bits conveyed by the signal-domain(SiD) symbols and the spatial-domain(SpD) light emitting diode(LED)-index patterns are coded by a protograph low-density parity-check(P-LDPC) code. Specifically, we propose a signal-domain symbol expanding and re-allocating(SSER) method for constructing a type of novel generalized spatial modulation(GSM) constellations, referred to as SSERGSM constellations, so as to boost the performance of the BICGSM-ID MIMO-VLC systems.Moreover, by applying a modified PEXIT(MPEXIT) algorithm, we further design a family of rate-compatible P-LDPC codes, referred to as enhanced accumulate-repeat-accumulate(EARA) codes,which possess both excellent decoding thresholds and linear-minimum-distance-growth property. Both analysis and simulation results illustrate that the proposed SSERGSM constellations and P-LDPC codes can remarkably improve the convergence and decoding performance of MIMO-VLC systems. Therefore, the proposed P-LDPC-coded SSERGSM-mapped BICGSMID configuration is envisioned as a promising transmission solution to satisfy the high-throughput requirement of MIMO-VLC applications.展开更多
A new scheme of super-resolution optical fluctuation imaging(SOFI)is proposed to broaden its application in the high-order cumulant reconstruction by optimizing blinking characteristics,eliminating noise in raw data a...A new scheme of super-resolution optical fluctuation imaging(SOFI)is proposed to broaden its application in the high-order cumulant reconstruction by optimizing blinking characteristics,eliminating noise in raw data and applying multi-resolution analysis in cumulant reconstruction.A motor-driven rotating mask optical modulation system is designed to adjust the excitation lightfield and allows for fast deployment.Active-modulated fluorescence fluctuation superresolution microscopy with multi-resolution analysis(AMF-MRA-SOFI)demonstrates enhanced resolution ability and reconstruction quality in experiments performed on sample of conventional dyes,achieving a resolution of 100 nm in the fourth order compared to conventional SOFI reconstruction.Furthermore,our approach combining expansion super-resolution achieved a resolution at-57 nm.展开更多
This review examines the state-of-the-art in spatial manipulation of ultrafast laser processing using dynamic light modulators,with a particular focus on liquid crystal-based systems.We discuss phase modulation strate...This review examines the state-of-the-art in spatial manipulation of ultrafast laser processing using dynamic light modulators,with a particular focus on liquid crystal-based systems.We discuss phase modulation strategies and highlight the current limitations and challenges in surface and bulk processing.Specifically,we emphasize the delicate balance between high-fidelity beam shaping and energy efficiency,both critical for surface and bulk processing applications.Given the inherent physical limitations of spatial light modulators such as spatial resolution,fill factor,and phase modulation range.We explore techniques developed to bridge the gap between desired intensity distributions and actual experimental beam profiles.We present various laser light modulation technologies and the main algorithmic strategies for obtaining modulation patterns.The paper includes application examples across a wide range of fields,from surgery to surface structuring,cutting,bulk photo-inscription of optical functions,and additive manufacturing,highlighting the significant enhancements in processing speed and precision due to spatial beam shaping.The diverse applications and the technological limitations underscore the need for adapted modulation pattern calculation methods.We discuss several advancements addressing these challenges,involving both experimental and algorithmic developments,including the recent incorporation of artificial intelligence.Additionally,we cover recent progress in phase and pulse front control based on spatial modulators,which introduces an extra control parameter for light excitation with high potential for achieving more controlled processing outcomes.展开更多
Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom a...Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom arrays,scalability is primarily constrained by the capacity to generate large numbers of optical tweezers,and conventional techniques using acousto-optic deflectors or spatial light modulators struggle to produce arrays much beyond∼10,000 tweezers.Moreover,these methods require additional microscope objectives to focus the light into micrometer-sized spots,which further complicates system integration and scalability.Here,we demonstrate the experimental generation of an optical tweezer array containing 280×280 spots using a metasurface,nearly an order of magnitude more than most existing systems.The metasurface leverages a large number of subwavelength phase-control pixels to engineer the wavefront of the incident light,enabling both large-scale tweezer generation and direct focusing into micron-scale spots without the need for a microscope.This result shifts the scalability bottleneck for atom arrays from the tweezer generation hardware to the available laser power.Furthermore,the array shows excellent intensity uniformity exceeding 90%,making it suitable for homogeneous single-atom loading and paving the way for trapping arrays of more than 10,000 atoms in the near future.展开更多
Spatial light modulators(SLM),capable of dynamically and spatially manipulating electromagnetic waves,have reshaped modern life in projection display and remote sensing.The progress of SLM will expedite next-generatio...Spatial light modulators(SLM),capable of dynamically and spatially manipulating electromagnetic waves,have reshaped modern life in projection display and remote sensing.The progress of SLM will expedite next-generation communication and biomedical imaging in the terahertz(THz)range.However,most current THz SLMs are adapted from optical alternatives that still need improvement in terms of uniformity,speed,and bandwidth.Here,we designed,fabricated,and characterized an 8×8THz SLM based on tunable liquid crystal metamaterial absorbers for THz single-pixel compressive imaging.We demonstrated dual-color compressive sensing(CS)imaging for dispersive objects utilizing the large frequency shift controlled by an external electric field.We developed auto-calibrated compressive sensing(ACS)algorithm to mitigate the impact of the spatially nonuniform THz incident beam and pixel modulation,which significantly improves the fidelity of reconstructed images.Furthermore,the complementary modulation at two absorption frequencies enables Hadamard masks with negative element values to be realized by frequency-switching,thereby halving the imaging time.The demonstrated imaging system paves a new route for THz single-pixel multispectral imaging with high reliability and low cost.展开更多
The resolution of the spatial light modulator(SLM)screen and the encoding algorithm of the computer-generated hologram are the primary limiting factors in the generation of large topological charge vortex beams.This p...The resolution of the spatial light modulator(SLM)screen and the encoding algorithm of the computer-generated hologram are the primary limiting factors in the generation of large topological charge vortex beams.This paper attempts to solve these problems by improving both the hardware and the algorithm.Theoretically,to overcome the limitations of beam waist radius,the amplitude profile function of large topological charge Laguerre–Gaussian(LG)beam is properly improved.Then,an experimental system employing a 4K phase-only SLM is set up,and the LG beams with topological charge up to 1200 are successfully generated.Furthermore,we discuss the effect of different beam waist radii on the generation of LG beams.Additionally,the function of the LG beam is further improved to generate an LG beam with a topological charge as high as1400.Our results set a new benchmark for generating large topological charge vortex beams,which can be widely used in precise measurement,sensing,and communication.展开更多
An integrated method based on optical and digital image processing is presented to suppress speckle in digital holography. A spatial light modulator is adopted to introduce random phases to the illuminating beam. Mult...An integrated method based on optical and digital image processing is presented to suppress speckle in digital holography. A spatial light modulator is adopted to introduce random phases to the illuminating beam. Multiple holograms are reconstructed and superimposed, and the intensity is averaged to smooth the noise. The adaptive algorithm based on the nonlocal means is designed to further suppress the speckle. The presented method is compared with other methods reduction is improved, and the proposed method is effective The experimental results show that speckle and feasible.展开更多
By using an amplitude-type spatial light modulator to load angular spectrum of Mathieu function distribution along a narrow annular pupils, the Durnin’s experimental setup is extended to generate various types of Mat...By using an amplitude-type spatial light modulator to load angular spectrum of Mathieu function distribution along a narrow annular pupils, the Durnin’s experimental setup is extended to generate various types of Mathieu beams. As a special type of Mathieu beams, Bessel beams are also generated using this optical setup. Furthermore, the optical morphology of the Mathieu beams family are also presented and analyzed.展开更多
A universal programmable multi-quantum-well（MQW） spatial light modulator（SLM） driving circuit is developed.With a twice scanning, it can generate programmable signals to drive a non-linear MQW SLM by using a softw...A universal programmable multi-quantum-well（MQW） spatial light modulator（SLM） driving circuit is developed.With a twice scanning, it can generate programmable signals to drive a non-linear MQW SLM by using a software preprocessing unit.By adjusting the switching network of the driving circuit, this circuit can reduce the switching noise and improve the output precision.The chip test results show that the driving voltage can swing from 0 to VDD, and its resolution could be close to 256 with a pixel area of only 65 × 65 μm2.展开更多
基金Projects(51875584,51875585,51975590)supported by the National Natural Science Foundation of China。
文摘Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,a femtosecond laser Bessel beam is proposed to process micro-FZP,which is modulated from a Gaussian beam to a Bessel annular beam.The processing time for FZP with an outer diameter of 60μm is reduced from 30 min to 1.5 min on an important semiconductor material gallium arsenide(GaAs),which significantly improves the processing efficiency.In the modulation process,a central ablation hole that has an adverse effect on the diffraction performance is produced,and the adverse effect is eliminated by superimposing the blazed grating hologram.Meanwhile,the FZP machined by spatial light modulator(SLM)has good morphology and higher diffraction efficiency,which provides a strong guarantee for the application of micro-FZP in computed tomography and solar photovoltaic cells.
基金Project supported by the National Natural Science Foundation of China （Nos 60578035, 50473040） and the Science Foundation of Jilin Province （Nos 20050520, 20050321-2）.
文摘The liquid crystal spatial light modulator （LC SLM） is very suitable for wavefront correction and optical testing and can produce a wavefront with large phase change and high accuracy. The LC SLM is composed of thousands of pixels and the pixel size and shape have effects on the diffractive characteristics of the LC SLM. This paper investigates the pixel effect on the phase of the wavefront with the scalar diffractive theory. The results show that the maximum optical path difference modulation is 41μm to produce the paraboloid wavefront with the peak to valley accuracy better than λ/10. Effects of the mismatch between the pixel and the period, and black matrix on the diffraction efficiency of the LC SLM are also analysed with the Fresnel phase lens model. The ability of the LC SLM is discussed for optical testing and wavefront correction based on the calculated results. It shows that the LC SLM can be used as a wavefront corrector and a compensator.
基金supports from National Natural Science Foundation of China (No.62235009).
文摘Spatial light modulators,as dynamic flat-panel optical devices,have witnessed rapid development over the past two decades,concomitant with the advancements in micro-and opto-electronic integration technology.In particular,liquid-crystal spatial light modulator(LC-SLM)technologies have been regarded as versatile tools for generating arbitrary optical fields and tailoring all degrees of freedom beyond just phase and amplitude.These devices have gained significant interest in the nascent field of structured light in space and time,facilitated by their ease of use and real-time light manipulation,fueling both fundamental research and practical applications.Here we provide an overview of the key working principles of LC-SLMs and review the significant progress made to date in their deployment for various applications,covering topics as diverse as beam shaping and steering,holography,optical trapping and tweezers,measurement,wavefront coding,optical vortex,and quantum optics.Finally,we conclude with an outlook on the potential opportunities and technical challenges in this rapidly developing field.
基金This work was financially supported by grants from the National Basic Research Program of China (973 Program)(No.2015CB352003)the National Natural Science Foundation of China (Nos.61377013,61335003,61378051,and 61427818)+1 种基金NSFC of Zhejiang province LR16F050001,Innovation Joint Research Center for iCPS (2015XZZX005-01)Open Foundation of the State Key Laboratory of Modern Optical Instrumentation.
文摘We report three-dimensional fluorescence emission difference(3D-FED)microscopy using a spatial light modulator(SLM).Zero phase,0–2vortex phase and binary 0-pi phase are loaded on the SLM to generate the corresponding solid,doughnut and z-axis hollow excitation spot,respectively.Our technique achieves super-resolved image by subtracting three di®erently acquired images with proper subtractive factors.Detailed theoretical analysis and simulation tests are proceeded to testify the performance of 3D-FED.Also,the improvement of lateral and axial resolution is demonstrated by imaging 100 nm°uorescent beads.The experiment yields lateral resolution of 140 nm and axial resolution of approximate 380 nm.
基金supported by the National Natural Science Foundation of China (Grant No. 60878048)the China Postdoctoral Science Foundation (Grant No. 20080440898)
文摘Liquid crystal spatial light modulator （LCSLM） realizing equal-intensity multiple beams often has some features, i.e., phase valley between two adjacent pixels, flybaek region when phase decreases immediately from 2~r to 0, and inevitable backplane curvature, which are different from those of most conventional diffractive optical elements （DOEs）, such as static DOEs. For optimal intensity uniformity, equal-intensity multi-beam generation must be considered for these artifacts. We present a tunable-grating method in which the intensity uniformity can be improved by considering the LCSLM artifacts. For instance, tuning phase modulation depth of the grating, called isosceles triangle multilevel phase grating （ITMPG）, can be used not only to improve the intensity uniformity, but also to fast steer four beams with narrow beamwidths, determined by the same effective aperture of ITMPG. Improved intensity uniformity and high relative diffraction efficiency are demonstrated through experiments with phase-only LCSLM.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61575076 and 61804148)the National Key Research and Development Plan of China(Grant No.2016YFB0402502)
文摘The extinction ratio and insertion loss of spatial light modulator are subject to the material problem, thus limiting its applications. One reflection-type silicon-based spatial light modulator with high reflective materials outside the Fabry-Perot cavity is demonstrated in this paper. The reflectivity values of the outside-cavity materials with different film layer numbers are simulated. The reflectivity values of 6-pair Ta2O5/SiO2 films at 1550 nm are experimentally verified to be as high as 99.9%. The surfaces of 6-pair Ta2O5/SiO2 films are smooth: their root-mean-square roughness values are as small as 0.53 nm. The insertion loss of the device at 1550 nm is only 1.2 dB. The high extinction ratio of the device at 1550 nm and 11 V is achieved to be 29.7 dB. The spatial light modulator has a high extinction ratio and low insertion loss for applications.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(Grant No.2020B0301030009)the National Key Research and Development Program of China(Grant No.2022YFA1604304)the National Natural Science Foundation of China(Grant No.92250305).
文摘Plasmonic modes within metal nanostructures play a pivotal role in various nanophotonic applications.However,a significant challenge arises from the fixed shapes of nanostructures post-fabrication,resulting in limited modes under ordinary illumination.A promising solution lies in far-field control facilitated by spatial light modulators(SLMs),which enable on-site,real-time,and non-destructive manipulation of plasmon excitation.Through the robust modulation of the incident light using SLMs,this approach enables the generation,optimization,and dynamic control of surface plasmon polariton(SPP)and localized surface plasmon(LSP)modes.The versatility of this technique introduces a rich array of tunable degrees of freedom to plasmon-enhanced spectroscopy,offering novel approaches for signal optimization and functional expansion in this field.This paper provides a comprehensive review of the generation and modulation of SPP and LSP modes through far-field control with SLMs and highlights the diverse applications of this optical technology in plasmon-enhanced spectroscopy.
文摘The combined use of the photoelectric and electro-optic properties of BSO crystal (Bi 12 SiO 20 ) leads to realize spatial light modulation.Under some condition,BSO crystal can become birefringent depending on a local illuminance.The relationship between the distributions of an illuminance and a birefringence will be discussed.This spatial light modulator can work in real-time. The experiment shows,in order to increase the sensitivity of BSO crystal,an electric field of 6 kV/cm at an atmosphere pressure of 15×10 5 Pa should be applied to BSO crystal.With BSO we have measured 3-dimensional deformation by means of real-time holography.
文摘The liquid crystal television spatial light modulator (LCTVSLM) characterized is usable in optical processing applications,e.g.,optical pattern recognition,associative memory, optical computing,correlation detection and optical data processing systems.The array performance and real-time optical correlation applications are reviewed.
基金supported by the National Natural Science Foundation of China (U2031210 and 11827804)Science Research from the China Manned Space Project (CMS-CSST-2021-A11 and CMS-CSST-2021-B04).
文摘The primary mirrors of current and future large telescopes always employ a segmented mirror configuration.The small but non-negligible gaps between neighboring segments cause additional diffraction,which restricts the performance of high-contrast coronagraph.To solve this problem,we propose a coronagraph system based on a single liquid crystal spatial light modulator(SLM).This spatial light modulator is used for amplitude apodization,and its feasibility and potential performance are demonstrated using a laboratory setup using the stochastic parallel gradient descent(SPGD)algorithm to control the spatial light modulator,which is based on point spread function(PSF)sensing and evaluation and optimized for maximum contrast in the discovery working area as a merit function.The system delivers a contrast in the order of 10−6,and shows excellent potential to be used in current and future large aperture telescopes,both on the ground and in space.
基金supported in part by the NSF of China under Grant 62322106,62071131the Guangdong Basic and Applied Basic Research Foundation under Grant 2022B1515020086+2 种基金the International Collaborative Research Program of Guangdong Science and Technology Department under Grant 2022A0505050070in part by the Open Research Fund of the State Key Laboratory of Integrated Services Networks under Grant ISN22-23the National Research Foundation,Singapore University of Technology Design under its Future Communications Research&Development Programme“Advanced Error Control Coding for 6G URLLC and mMTC”Grant No.FCP-NTU-RG-2022-020.
文摘This paper investigates the bit-interleaved coded generalized spatial modulation(BICGSM) with iterative decoding(BICGSM-ID) for multiple-input multiple-output(MIMO) visible light communications(VLC). In the BICGSM-ID scheme, the information bits conveyed by the signal-domain(SiD) symbols and the spatial-domain(SpD) light emitting diode(LED)-index patterns are coded by a protograph low-density parity-check(P-LDPC) code. Specifically, we propose a signal-domain symbol expanding and re-allocating(SSER) method for constructing a type of novel generalized spatial modulation(GSM) constellations, referred to as SSERGSM constellations, so as to boost the performance of the BICGSM-ID MIMO-VLC systems.Moreover, by applying a modified PEXIT(MPEXIT) algorithm, we further design a family of rate-compatible P-LDPC codes, referred to as enhanced accumulate-repeat-accumulate(EARA) codes,which possess both excellent decoding thresholds and linear-minimum-distance-growth property. Both analysis and simulation results illustrate that the proposed SSERGSM constellations and P-LDPC codes can remarkably improve the convergence and decoding performance of MIMO-VLC systems. Therefore, the proposed P-LDPC-coded SSERGSM-mapped BICGSMID configuration is envisioned as a promising transmission solution to satisfy the high-throughput requirement of MIMO-VLC applications.
基金supported by the National Natural Science Foundation of China(62175034,62175036,32271510)the National Key R&D Program of China(2021YFF0502900)+2 种基金the Science and Technology Research Program of Shanghai(Grant No.19DZ2282100)the Shanghai Key Laboratory of Metasurfaces for Light Manipulation(23dz2260100)the Shanghai Engineering Technology Research Center of Hair Medicine(19DZ2250500).
文摘A new scheme of super-resolution optical fluctuation imaging(SOFI)is proposed to broaden its application in the high-order cumulant reconstruction by optimizing blinking characteristics,eliminating noise in raw data and applying multi-resolution analysis in cumulant reconstruction.A motor-driven rotating mask optical modulation system is designed to adjust the excitation lightfield and allows for fast deployment.Active-modulated fluorescence fluctuation superresolution microscopy with multi-resolution analysis(AMF-MRA-SOFI)demonstrates enhanced resolution ability and reconstruction quality in experiments performed on sample of conventional dyes,achieving a resolution of 100 nm in the fourth order compared to conventional SOFI reconstruction.Furthermore,our approach combining expansion super-resolution achieved a resolution at-57 nm.
基金supported by the French ANRT agence nationale de la recherche technologique under the CIFRE conventions industrielles de formation par la recherche framework.
文摘This review examines the state-of-the-art in spatial manipulation of ultrafast laser processing using dynamic light modulators,with a particular focus on liquid crystal-based systems.We discuss phase modulation strategies and highlight the current limitations and challenges in surface and bulk processing.Specifically,we emphasize the delicate balance between high-fidelity beam shaping and energy efficiency,both critical for surface and bulk processing applications.Given the inherent physical limitations of spatial light modulators such as spatial resolution,fill factor,and phase modulation range.We explore techniques developed to bridge the gap between desired intensity distributions and actual experimental beam profiles.We present various laser light modulation technologies and the main algorithmic strategies for obtaining modulation patterns.The paper includes application examples across a wide range of fields,from surgery to surface structuring,cutting,bulk photo-inscription of optical functions,and additive manufacturing,highlighting the significant enhancements in processing speed and precision due to spatial beam shaping.The diverse applications and the technological limitations underscore the need for adapted modulation pattern calculation methods.We discuss several advancements addressing these challenges,involving both experimental and algorithmic developments,including the recent incorporation of artificial intelligence.Additionally,we cover recent progress in phase and pulse front control based on spatial modulators,which introduces an extra control parameter for light excitation with high potential for achieving more controlled processing outcomes.
基金supported by the National Natural Science Foundation of China (Grant No.92576208)Tsinghua University Initiative Scientific Research Program+1 种基金Beijing Science and Technology Planning ProjectTsinghua University Dushi Program。
文摘Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom arrays,scalability is primarily constrained by the capacity to generate large numbers of optical tweezers,and conventional techniques using acousto-optic deflectors or spatial light modulators struggle to produce arrays much beyond∼10,000 tweezers.Moreover,these methods require additional microscope objectives to focus the light into micrometer-sized spots,which further complicates system integration and scalability.Here,we demonstrate the experimental generation of an optical tweezer array containing 280×280 spots using a metasurface,nearly an order of magnitude more than most existing systems.The metasurface leverages a large number of subwavelength phase-control pixels to engineer the wavefront of the incident light,enabling both large-scale tweezer generation and direct focusing into micron-scale spots without the need for a microscope.This result shifts the scalability bottleneck for atom arrays from the tweezer generation hardware to the available laser power.Furthermore,the array shows excellent intensity uniformity exceeding 90%,making it suitable for homogeneous single-atom loading and paving the way for trapping arrays of more than 10,000 atoms in the near future.
基金supported by the National Key Research and Development Program of China(2017YFA0700202,2021YFB2800701)National Nature Science Foundation of China(61731010,62071217,61971465,62027807,61871212,62025108,62035014)Fundamental Research Funds for the Central Universities,and Research Fund for Jiangsu Key Laboratory of Advanced Techniques for Manipulatinp Electromagnetic Waves.
文摘Spatial light modulators(SLM),capable of dynamically and spatially manipulating electromagnetic waves,have reshaped modern life in projection display and remote sensing.The progress of SLM will expedite next-generation communication and biomedical imaging in the terahertz(THz)range.However,most current THz SLMs are adapted from optical alternatives that still need improvement in terms of uniformity,speed,and bandwidth.Here,we designed,fabricated,and characterized an 8×8THz SLM based on tunable liquid crystal metamaterial absorbers for THz single-pixel compressive imaging.We demonstrated dual-color compressive sensing(CS)imaging for dispersive objects utilizing the large frequency shift controlled by an external electric field.We developed auto-calibrated compressive sensing(ACS)algorithm to mitigate the impact of the spatially nonuniform THz incident beam and pixel modulation,which significantly improves the fidelity of reconstructed images.Furthermore,the complementary modulation at two absorption frequencies enables Hadamard masks with negative element values to be realized by frequency-switching,thereby halving the imaging time.The demonstrated imaging system paves a new route for THz single-pixel multispectral imaging with high reliability and low cost.
基金supported by the National Natural Science Foundation of China(Nos.62173342 and 61805283)the Key Research Projects of Foundation Strengthening Program(No.2019-JCJQ-ZD)。
文摘The resolution of the spatial light modulator(SLM)screen and the encoding algorithm of the computer-generated hologram are the primary limiting factors in the generation of large topological charge vortex beams.This paper attempts to solve these problems by improving both the hardware and the algorithm.Theoretically,to overcome the limitations of beam waist radius,the amplitude profile function of large topological charge Laguerre–Gaussian(LG)beam is properly improved.Then,an experimental system employing a 4K phase-only SLM is set up,and the LG beams with topological charge up to 1200 are successfully generated.Furthermore,we discuss the effect of different beam waist radii on the generation of LG beams.Additionally,the function of the LG beam is further improved to generate an LG beam with a topological charge as high as1400.Our results set a new benchmark for generating large topological charge vortex beams,which can be widely used in precise measurement,sensing,and communication.
基金supported by the National Natural Science Foundation of China(No.61177018)the Program for New Century Excellent Talents in University(No.NECT-11-0596)+1 种基金the Key Program of Beijing Sci-ence and Technology Plan(No.D121100004812001)Beijing Nova Program(No.2011066)
文摘An integrated method based on optical and digital image processing is presented to suppress speckle in digital holography. A spatial light modulator is adopted to introduce random phases to the illuminating beam. Multiple holograms are reconstructed and superimposed, and the intensity is averaged to smooth the noise. The adaptive algorithm based on the nonlocal means is designed to further suppress the speckle. The presented method is compared with other methods reduction is improved, and the proposed method is effective The experimental results show that speckle and feasible.
基金Project supported by the National Natural Science Foundation of China(Grant No.11674288)
文摘By using an amplitude-type spatial light modulator to load angular spectrum of Mathieu function distribution along a narrow annular pupils, the Durnin’s experimental setup is extended to generate various types of Mathieu beams. As a special type of Mathieu beams, Bessel beams are also generated using this optical setup. Furthermore, the optical morphology of the Mathieu beams family are also presented and analyzed.
基金supported by the International Collaboration Plan for Science and Technology of the Chinese Ministry of Science and Technolog(No. 2008DFB10040)
文摘A universal programmable multi-quantum-well（MQW） spatial light modulator（SLM） driving circuit is developed.With a twice scanning, it can generate programmable signals to drive a non-linear MQW SLM by using a software preprocessing unit.By adjusting the switching network of the driving circuit, this circuit can reduce the switching noise and improve the output precision.The chip test results show that the driving voltage can swing from 0 to VDD, and its resolution could be close to 256 with a pixel area of only 65 × 65 μm2.
