To reduce the computing time of composite computer-generated holograms （CGHs） gen- eration based upon the angular projection algorithm for holographic three-dimensional （3D） display, a grid-based holographic displ...To reduce the computing time of composite computer-generated holograms （CGHs） gen- eration based upon the angular projection algorithm for holographic three-dimensional （3D） display, a grid-based holographic display （ GHD ） scheme was designed. The grid computing technology was applied to numerically process the different angular projections of an object in distributed-parallel manner to create the corresponding CGHs. The whole treatment of a projection was regarded as a job executed on the grid node machine. The number of jobs which were submitted to grid nodes, therefore, was equal to that of the projections of the object. A Condor-based grid testbed was constructed to verify the feasibility of the GHD scheme, and a graphical user interface （GUI） program and several service modules were developed for it. A 3D terrain model as an example was processed on the testbed. The result showed that the scheme was feasible and able to improve the execution elficiency greatly.展开更多
An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, clo...An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable.展开更多
The airborne systems complied with the ARINC661 standard are called the A661 member system. The software for the system is referred to the A661 airborne software in the research. Theoretically,some critical technology...The airborne systems complied with the ARINC661 standard are called the A661 member system. The software for the system is referred to the A661 airborne software in the research. Theoretically,some critical technology of the A661 airborne software are analyzed in this paper and the research results have been utilized for the advanced civil aircraft in practice.展开更多
A switchable autostereoscopic 3-dimensional(3D) display device with wide color gamut is introduced in this paper. In conjunction with a novel directional quantum-dot(QD) backlight, the precise scanning control strateg...A switchable autostereoscopic 3-dimensional(3D) display device with wide color gamut is introduced in this paper. In conjunction with a novel directional quantum-dot(QD) backlight, the precise scanning control strategy, and the eye-tracking system, this spatial-sequential solution enables our autostereoscopic display to combine all the advantages of full resolution,wide color gamut, low crosstalk, and switchable 2D/3D. And also, we fabricated an autostereoscopic display prototype and demonstrated its performances effectively. The results indicate that our system can both break the limitation of viewing position and provide high-quality 3D images. We present two working modes in this system. In the spatial-sequential mode,the crosstalk is about 6%. In the time-multiplexed mode, the viewer should wear auxiliary and the crosstalk is about 1%,just next to that of a commercial 3D display(BENQ XL2707-B and View Sonic VX2268 WM). Additionally, our system is also completely compatible with active shutter glasses and its 3D resolution is same as its 2D resolution. Because of the excellent properties of the QD material, the color gamut can be widely extended to 77.98% according to the ITU-R recommendation BT.2020(Rec.2020).展开更多
In this review we will focus on recent progress in the field of two-dimensional（2D） and three-dimensional（3D）display technologies.We present the current display materials and their applications,including organic l...In this review we will focus on recent progress in the field of two-dimensional（2D） and three-dimensional（3D）display technologies.We present the current display materials and their applications,including organic light-emitting diodes（OLEDs）,flexible OLEDs quantum dot light emitting diodes（QLEDs）,active-matrix organic light emitting diodes（AMOLEDs）,electronic paper（E-paper）,curved displays,stereoscopic 3D displays,volumetric 3D displays,light field3 D displays,and holographic 3D displays.Conventional 2D display devices,such as liquid crystal devices（LCDs） often result in ambiguity in high-dimensional data images because of lacking true depth information.This review thus provides a detailed description of 3D display technologies.展开更多
In order to achieve a clear and steady swept-volume display,the method of swept-volume display based on cylindrical space projection was presented. One projector generated the image volume in π× 70 mm × 70 ...In order to achieve a clear and steady swept-volume display,the method of swept-volume display based on cylindrical space projection was presented. One projector generated the image volume in π× 70 mm × 70 mm × 150 mm space. Experimentally,the resolution of images was 800 pixel × 600 pixel × 360 pixel,which resulted in almost 345 million voxels. In order to achieve space voxels with uniform brightness, curved reflectors were also designed. In addition,the match conditions between triangles and the scanning planes in the volume space were classified and a sweptvolume graphics engine based on embedded platform was designed.The image rendering the hardware foundation for three-dimensional( 3D) dynamic images generation was achieved. Demonstrated in the experiments,light source utilization of the second-generation system based on curved mirror is about three times brighter than the firstgeneration 3D minitor based on flat mirror,and this system is able to display color,clear and well-proportioned 3D images in brighter room light.展开更多
We propose a cross-talk-free integral imaging 3D display based on a pyramid pinhole array. The pyramid pinhole array is used to provide a point light source array. Since the generated point light source array is behin...We propose a cross-talk-free integral imaging 3D display based on a pyramid pinhole array. The pyramid pinhole array is used to provide a point light source array. Since the generated point light source array is behind a transmission-type display panel that displays an elemental image array, the pseudoscopic problem can be resolved. By setting the appropriate parameters for the pyramid pinhole array, the cross talk can be eliminated.We experimentally verify the reconstruction of the orthoscopic and cross-talk-free 3D images using the proposed 3D display.展开更多
Multiple three-dimensional （3D） display technologies are reviewed. The display mechanisms discussed in this paper are classified into two categories： holographic display in wave optics and light field display in ra...Multiple three-dimensional （3D） display technologies are reviewed. The display mechanisms discussed in this paper are classified into two categories： holographic display in wave optics and light field display in ray optics, which present the 3D optical wave field in two different ways. Key technical characteristics of the optical systems and the depth cues of human visual system are analyzed. It is to be expected that these 3D display technologies will achieve practical applications with the increase of the optical system bandwidth.展开更多
In the late 1980s the first laparoscopic cholecystectomies were performed prompting a sudden rise in technological innovations as the benefits and feasibility of minimal access surgery became recognised.Monocular lapa...In the late 1980s the first laparoscopic cholecystectomies were performed prompting a sudden rise in technological innovations as the benefits and feasibility of minimal access surgery became recognised.Monocular laparoscopes provided only two-dimensional(2D) viewing with reduced depth perception and contributed to an extended learning curve.Attention turned to producing a usable three-dimensional(3D) endoscopic view for surgeons;utilising different technologies for image capture and image projection.These evolving visual systems have been assessed in various research environments with conflicting outcomes of success and usability,and no overall consensus to their benefit.This review article aims to provide an explanation of the different types of technologies,summarise the published literature evaluating 3D vs 2D laparoscopy,to explain the conflicting outcomes,and discuss the current consensus view.展开更多
The red, green, and blue upconversion properties of Er^3＋/Tm^3＋/Yb^3＋-codoped oxyhalide tellurite glasses were studied under 980 nm LD excitation. The intense red （657 nm）, green （530 and 545 nm）, and blue （47...The red, green, and blue upconversion properties of Er^3＋/Tm^3＋/Yb^3＋-codoped oxyhalide tellurite glasses were studied under 980 nm LD excitation. The intense red （657 nm）, green （530 and 545 nm）, and blue （476 nm） emissions were simultaneously observed at room temperature. The results showed that the mixed halide modified tellurite glass （TZFCB） had strong upconversion emissions. The effect of halide on upconversion intensity was observed and discussed, and possible upconversion mechanisms were evaluated. The intense red, green, and blue upconversion luminescence of Er^3＋/Tm^3＋/Yb^3＋-codoped oxyhalide tellurite glasses might be a potentially useful material for developing three-dimensional displays applications.展开更多
A near infrared to visible blue, green, and red upconversion luminescence in a Tb^3＋-doped CaO-Al2O3-SiO2 glass was studied, which was excited using 800 nm femtosecond laser irradiation. The upconversion luminescence...A near infrared to visible blue, green, and red upconversion luminescence in a Tb^3＋-doped CaO-Al2O3-SiO2 glass was studied, which was excited using 800 nm femtosecond laser irradiation. The upconversion luminescence was attributed to ^5D3→^7F5, ^5D3→^7F4, ^5D3→^7F3, ^5D4→^7F6, ^5D4→^7F5, ^5D4→^7F4, and ^5D4→^7F3 transitions of Tb^3＋. The relationship between upconversion luminescence intensity and the pump power indicated that a three-photon simultaneous absorption process was dominant in this upconversion luminescence. The intense red, green, and blue upconversion luminescence of Tb^3＋-doped CaO-Al2O3-SiO2 glass may be potentially useful in developing three-dimensional display applications.展开更多
In capsule endoscopy(CE), there is research to develop hardware that enables ‘‘real'' three-dimensional(3-D) video. However, it should not be forgotten that ‘‘true'' 3-D requires dual video images....In capsule endoscopy(CE), there is research to develop hardware that enables ‘‘real'' three-dimensional(3-D) video. However, it should not be forgotten that ‘‘true'' 3-D requires dual video images. Inclusion of two cameras within the shell of a capsule endoscope though might be unwieldy at present. Therefore, in an attempt to approximate a 3-D reconstruction of the digestive tract surface, a software that recovers information-using gradual variation of shading-from monocular two-dimensional CE images has been proposed. Light reflections on the surface of the digestive tract are still a significant problem. Therefore, a phantom model and simulator has been constructed in an attempt to check the validity of a highlight suppression algorithm. Our results confirm that 3-D representation software performs better with simultaneous application of a highlight reduction algorithm. Furthermore, 3-D representation follows a good approximation of the real distance to the lumen surface.展开更多
This paper analyzes the technical characteristic of three-dimensional display technology （3DTV） system and some core technologies yet to be solved. It points out the ways to solve these problems and presents an effe...This paper analyzes the technical characteristic of three-dimensional display technology （3DTV） system and some core technologies yet to be solved. It points out the ways to solve these problems and presents an effective solution for thediscomfort of watching the three-dimensional TV.展开更多
This thesis paper is a brief summary of user centered design, (particularly in the situation of under the battlefield), which incorporates the related information after reviewing many other papers. A display screen us...This thesis paper is a brief summary of user centered design, (particularly in the situation of under the battlefield), which incorporates the related information after reviewing many other papers. A display screen user requires an ability to provide proper information while considering a variety of information in a short period. While operating the display screen, the user is heavily pressed for time as the missions are allocated through many different steps of orders. In addition, since a failure would cause fatal damage or cause further defeat, this increases the pressure of time. The right environment for operating a display screen is most useful when the user is in the most vulnerable time period or long-term continuous operation of the display screen. In that kind of sterile environment, the operating display screen is there to help the user’s decisions for the matter at hand, in this it should follow the user centered design and improve the user’s handiness and use. Furthermore, the information should be provided in accordance with the user's informational and perceptional process, and the capacity of the information process should be improved with the movement through each process and step. This thesis paper can be used as a reference material when designing the display screen in order to apply a user’s experiences.展开更多
Conventional stereoscopic three-dimensional displays suffer from vergenceaccommodation conflict because the stimulus to accommodation is fixed by the display panel and viewing optics,but that to vergence changes with ...Conventional stereoscopic three-dimensional displays suffer from vergenceaccommodation conflict because the stimulus to accommodation is fixed by the display panel and viewing optics,but that to vergence changes with image contents.With the recent rapid development of head-mounted displays,several methods have been proposed to offer the accommodation cues,among which multifocal display technology is an effective and practical solution.The first two decades of this century has witnessed the fast growth of multifocal displays from basic concept to mature implementations.This review systematically presents the state-of-the-art multifocal display design and development.Firstly,a comprehensive classification of numerous potential optical architectures to provide the multiplanar functionality is introduced,based on how the information is multiplexed and how the focal planes are generated.Next,the strengths and obstacles of reported or potential designs in each category are analyzed and compared with each other.In addition to enabling optics,the image rendering approaches for the multifocal planes are also described.This review presents a sufficient collection of past designs and is expected to offer a roadmap for future research and development of multifocal displays.展开更多
The excited state absorption upconversion of Pr(0.5)Yb(3):ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was fo...The excited state absorption upconversion of Pr(0.5)Yb(3):ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 631.8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3+)→1I6(Pr3+) and 1G4(Pr3+)→3P1(Pr3+)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3+)→3P2(Pr3+), and the 803.7 nm upconversion excitation transition 3H6(Pr3+)→1D2(Pr3+). The upconversion excitation transition 1G4(Pr3+)→1I6(Pr3+) is strong because its oscillator strength f = 23.040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3):ZBLAN induced by one laser and one continuous normal light simultaneously.展开更多
In the face of the energy revolution and industrial change in the new era,intelligent coal mining is the only way to achieve high-quality development of the coal industry.Intelligent coal mining has endowed the coal m...In the face of the energy revolution and industrial change in the new era,intelligent coal mining is the only way to achieve high-quality development of the coal industry.Intelligent coal mining has endowed the coal mine geological guarantee system with new connotations and promoted the higher-level development of coal mine geological guarantee technology.The significance of the geological guarantee system in the entire process of coal mining is systematically analyzed.The research and application status of surface,borehole,and“four-while”detection technology is reviewed in detail.The key technologies and development progress of intelligent geological assurance are introduced,and the future development direction of intelligent geological guarantee systems in China is comprehensively considered.High-precision detection results are the basis of geological guarantee.Based on conventional three-dimensional(3D)seismic exploration technology,3D seismic high-precision imaging methods,intelligent identification methods of geological structures,intelligent inversion of stratum parameters,joint interpretation of reflected and diffracted waves for small-scale geological anomalies,and key technologies of underground exploration,which provide high-precision detection results for geological guarantee,are investigated.In terms of the construction of dynamic geological models,the dynamic detection technology of coal-rock interface with mining based on air-coupled radar has been proposed,and the significance of an online monitoring system is discussed.Based on the large amount of exploration data,the real-time data processing and visualization software and dynamic update method of the 3D geological model are established.This study systematically classified the key technologies of coal mine geological guarantee,specified the future direction of intelligent geological guarantee,and provided a reference for the development of intelligent mining geological assurance systems in coal mines.展开更多
文摘To reduce the computing time of composite computer-generated holograms （CGHs） gen- eration based upon the angular projection algorithm for holographic three-dimensional （3D） display, a grid-based holographic display （ GHD ） scheme was designed. The grid computing technology was applied to numerically process the different angular projections of an object in distributed-parallel manner to create the corresponding CGHs. The whole treatment of a projection was regarded as a job executed on the grid node machine. The number of jobs which were submitted to grid nodes, therefore, was equal to that of the projections of the object. A Condor-based grid testbed was constructed to verify the feasibility of the GHD scheme, and a graphical user interface （GUI） program and several service modules were developed for it. A 3D terrain model as an example was processed on the testbed. The result showed that the scheme was feasible and able to improve the execution elficiency greatly.
基金Project(51274250)supported by the National Natural Science Foundation of ChinaProject(2012BAK09B02-05)supported by the National Key Technology R&D Program during the 12th Five-year Plan of China
文摘An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable.
文摘The airborne systems complied with the ARINC661 standard are called the A661 member system. The software for the system is referred to the A661 airborne software in the research. Theoretically,some critical technology of the A661 airborne software are analyzed in this paper and the research results have been utilized for the advanced civil aircraft in practice.
基金Project supported by the National Key R&D Program of China(Grant No.2016YFB0401503)the R&D Plan of Jiangsu Science and Technology Department,China(Grant No.BE2016173)
文摘A switchable autostereoscopic 3-dimensional(3D) display device with wide color gamut is introduced in this paper. In conjunction with a novel directional quantum-dot(QD) backlight, the precise scanning control strategy, and the eye-tracking system, this spatial-sequential solution enables our autostereoscopic display to combine all the advantages of full resolution,wide color gamut, low crosstalk, and switchable 2D/3D. And also, we fabricated an autostereoscopic display prototype and demonstrated its performances effectively. The results indicate that our system can both break the limitation of viewing position and provide high-quality 3D images. We present two working modes in this system. In the spatial-sequential mode,the crosstalk is about 6%. In the time-multiplexed mode, the viewer should wear auxiliary and the crosstalk is about 1%,just next to that of a commercial 3D display(BENQ XL2707-B and View Sonic VX2268 WM). Additionally, our system is also completely compatible with active shutter glasses and its 3D resolution is same as its 2D resolution. Because of the excellent properties of the QD material, the color gamut can be widely extended to 77.98% according to the ITU-R recommendation BT.2020(Rec.2020).
文摘In this review we will focus on recent progress in the field of two-dimensional（2D） and three-dimensional（3D）display technologies.We present the current display materials and their applications,including organic light-emitting diodes（OLEDs）,flexible OLEDs quantum dot light emitting diodes（QLEDs）,active-matrix organic light emitting diodes（AMOLEDs）,electronic paper（E-paper）,curved displays,stereoscopic 3D displays,volumetric 3D displays,light field3 D displays,and holographic 3D displays.Conventional 2D display devices,such as liquid crystal devices（LCDs） often result in ambiguity in high-dimensional data images because of lacking true depth information.This review thus provides a detailed description of 3D display technologies.
基金Shanghai Committee of Science and Technology,China(No.14511108200)
文摘In order to achieve a clear and steady swept-volume display,the method of swept-volume display based on cylindrical space projection was presented. One projector generated the image volume in π× 70 mm × 70 mm × 150 mm space. Experimentally,the resolution of images was 800 pixel × 600 pixel × 360 pixel,which resulted in almost 345 million voxels. In order to achieve space voxels with uniform brightness, curved reflectors were also designed. In addition,the match conditions between triangles and the scanning planes in the volume space were classified and a sweptvolume graphics engine based on embedded platform was designed.The image rendering the hardware foundation for three-dimensional( 3D) dynamic images generation was achieved. Demonstrated in the experiments,light source utilization of the second-generation system based on curved mirror is about three times brighter than the firstgeneration 3D minitor based on flat mirror,and this system is able to display color,clear and well-proportioned 3D images in brighter room light.
基金supported by the “973” Program under Grant No. 2013CB328802the NSFC under Grant Nos. 61320106015, 61405129, and 61377018the “863” Program under Grant No. 2012AA011901
文摘We propose a cross-talk-free integral imaging 3D display based on a pyramid pinhole array. The pyramid pinhole array is used to provide a point light source array. Since the generated point light source array is behind a transmission-type display panel that displays an elemental image array, the pseudoscopic problem can be resolved. By setting the appropriate parameters for the pyramid pinhole array, the cross talk can be eliminated.We experimentally verify the reconstruction of the orthoscopic and cross-talk-free 3D images using the proposed 3D display.
基金supported by the National Basic Research Program of China(No.2013CB328801)the National Natural Science Foundation of China(No.61205013)
文摘Multiple three-dimensional （3D） display technologies are reviewed. The display mechanisms discussed in this paper are classified into two categories： holographic display in wave optics and light field display in ray optics, which present the 3D optical wave field in two different ways. Key technical characteristics of the optical systems and the depth cues of human visual system are analyzed. It is to be expected that these 3D display technologies will achieve practical applications with the increase of the optical system bandwidth.
文摘In the late 1980s the first laparoscopic cholecystectomies were performed prompting a sudden rise in technological innovations as the benefits and feasibility of minimal access surgery became recognised.Monocular laparoscopes provided only two-dimensional(2D) viewing with reduced depth perception and contributed to an extended learning curve.Attention turned to producing a usable three-dimensional(3D) endoscopic view for surgeons;utilising different technologies for image capture and image projection.These evolving visual systems have been assessed in various research environments with conflicting outcomes of success and usability,and no overall consensus to their benefit.This review article aims to provide an explanation of the different types of technologies,summarise the published literature evaluating 3D vs 2D laparoscopy,to explain the conflicting outcomes,and discuss the current consensus view.
基金supported by the National Natural Science Foundation of China (60508014 and 50772102)Program for New Century Excellent Talents in University (NCET-07-0786)the Natural Science Foundation of Zhejiang Province (R406007)
文摘The red, green, and blue upconversion properties of Er^3＋/Tm^3＋/Yb^3＋-codoped oxyhalide tellurite glasses were studied under 980 nm LD excitation. The intense red （657 nm）, green （530 and 545 nm）, and blue （476 nm） emissions were simultaneously observed at room temperature. The results showed that the mixed halide modified tellurite glass （TZFCB） had strong upconversion emissions. The effect of halide on upconversion intensity was observed and discussed, and possible upconversion mechanisms were evaluated. The intense red, green, and blue upconversion luminescence of Er^3＋/Tm^3＋/Yb^3＋-codoped oxyhalide tellurite glasses might be a potentially useful material for developing three-dimensional displays applications.
基金supported by the Education Department of Zhejiang Province (20050359)
文摘A near infrared to visible blue, green, and red upconversion luminescence in a Tb^3＋-doped CaO-Al2O3-SiO2 glass was studied, which was excited using 800 nm femtosecond laser irradiation. The upconversion luminescence was attributed to ^5D3→^7F5, ^5D3→^7F4, ^5D3→^7F3, ^5D4→^7F6, ^5D4→^7F5, ^5D4→^7F4, and ^5D4→^7F3 transitions of Tb^3＋. The relationship between upconversion luminescence intensity and the pump power indicated that a three-photon simultaneous absorption process was dominant in this upconversion luminescence. The intense red, green, and blue upconversion luminescence of Tb^3＋-doped CaO-Al2O3-SiO2 glass may be potentially useful in developing three-dimensional display applications.
文摘In capsule endoscopy(CE), there is research to develop hardware that enables ‘‘real'' three-dimensional(3-D) video. However, it should not be forgotten that ‘‘true'' 3-D requires dual video images. Inclusion of two cameras within the shell of a capsule endoscope though might be unwieldy at present. Therefore, in an attempt to approximate a 3-D reconstruction of the digestive tract surface, a software that recovers information-using gradual variation of shading-from monocular two-dimensional CE images has been proposed. Light reflections on the surface of the digestive tract are still a significant problem. Therefore, a phantom model and simulator has been constructed in an attempt to check the validity of a highlight suppression algorithm. Our results confirm that 3-D representation software performs better with simultaneous application of a highlight reduction algorithm. Furthermore, 3-D representation follows a good approximation of the real distance to the lumen surface.
基金supported by the National Natural Science Foundation of China(Grant No.60832003)the Science and Technology Commission of Shanghai Municipality(Grant No.10510500500)the Key Laboratory of Advanced Display and System Applications(Shanghai University),Ministry of Education,China(Grant No.P200801)
文摘This paper analyzes the technical characteristic of three-dimensional display technology （3DTV） system and some core technologies yet to be solved. It points out the ways to solve these problems and presents an effective solution for thediscomfort of watching the three-dimensional TV.
文摘This thesis paper is a brief summary of user centered design, (particularly in the situation of under the battlefield), which incorporates the related information after reviewing many other papers. A display screen user requires an ability to provide proper information while considering a variety of information in a short period. While operating the display screen, the user is heavily pressed for time as the missions are allocated through many different steps of orders. In addition, since a failure would cause fatal damage or cause further defeat, this increases the pressure of time. The right environment for operating a display screen is most useful when the user is in the most vulnerable time period or long-term continuous operation of the display screen. In that kind of sterile environment, the operating display screen is there to help the user’s decisions for the matter at hand, in this it should follow the user centered design and improve the user’s handiness and use. Furthermore, the information should be provided in accordance with the user's informational and perceptional process, and the capacity of the information process should be improved with the movement through each process and step. This thesis paper can be used as a reference material when designing the display screen in order to apply a user’s experiences.
文摘Conventional stereoscopic three-dimensional displays suffer from vergenceaccommodation conflict because the stimulus to accommodation is fixed by the display panel and viewing optics,but that to vergence changes with image contents.With the recent rapid development of head-mounted displays,several methods have been proposed to offer the accommodation cues,among which multifocal display technology is an effective and practical solution.The first two decades of this century has witnessed the fast growth of multifocal displays from basic concept to mature implementations.This review systematically presents the state-of-the-art multifocal display design and development.Firstly,a comprehensive classification of numerous potential optical architectures to provide the multiplanar functionality is introduced,based on how the information is multiplexed and how the focal planes are generated.Next,the strengths and obstacles of reported or potential designs in each category are analyzed and compared with each other.In addition to enabling optics,the image rendering approaches for the multifocal planes are also described.This review presents a sufficient collection of past designs and is expected to offer a roadmap for future research and development of multifocal displays.
基金the National Natural Science Foundation of China (Grant Nos. 19874033 , 10174008) the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry.
文摘The excited state absorption upconversion of Pr(0.5)Yb(3):ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 631.8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3+)→1I6(Pr3+) and 1G4(Pr3+)→3P1(Pr3+)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3+)→3P2(Pr3+), and the 803.7 nm upconversion excitation transition 3H6(Pr3+)→1D2(Pr3+). The upconversion excitation transition 1G4(Pr3+)→1I6(Pr3+) is strong because its oscillator strength f = 23.040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3):ZBLAN induced by one laser and one continuous normal light simultaneously.
基金National Natural Science Foundation of China(No.42204142)Major Program of the National Natural Science Foundation of China(No.52394192)+1 种基金Fundamental Research Funds for the Central Universities,China(No.00007809)Interdisciplinary Research Project for Young Teachers of USTB(Fundamental Research Funds for the Central Universities,No.FRF-IDRY-23-016).
文摘In the face of the energy revolution and industrial change in the new era,intelligent coal mining is the only way to achieve high-quality development of the coal industry.Intelligent coal mining has endowed the coal mine geological guarantee system with new connotations and promoted the higher-level development of coal mine geological guarantee technology.The significance of the geological guarantee system in the entire process of coal mining is systematically analyzed.The research and application status of surface,borehole,and“four-while”detection technology is reviewed in detail.The key technologies and development progress of intelligent geological assurance are introduced,and the future development direction of intelligent geological guarantee systems in China is comprehensively considered.High-precision detection results are the basis of geological guarantee.Based on conventional three-dimensional(3D)seismic exploration technology,3D seismic high-precision imaging methods,intelligent identification methods of geological structures,intelligent inversion of stratum parameters,joint interpretation of reflected and diffracted waves for small-scale geological anomalies,and key technologies of underground exploration,which provide high-precision detection results for geological guarantee,are investigated.In terms of the construction of dynamic geological models,the dynamic detection technology of coal-rock interface with mining based on air-coupled radar has been proposed,and the significance of an online monitoring system is discussed.Based on the large amount of exploration data,the real-time data processing and visualization software and dynamic update method of the 3D geological model are established.This study systematically classified the key technologies of coal mine geological guarantee,specified the future direction of intelligent geological guarantee,and provided a reference for the development of intelligent mining geological assurance systems in coal mines.
