Laser diode stacks are interesting laser sources for active imaging illuminators. They allow the accumulation of large amounts of energy in multi-pulse mode, which is well suited for long-range image recording. Even when laser diode stacks are equipped with fast-axis collimation (FAC) and slow-axis collimation (SAC) microlenses, their beam parameter product (BPP) are not compatible with a direct use in highly efficient and compact illuminators. This is particularly true when narrow divergences are required such as for long range applications. To overcome these difficulties, we conducted investigations in three different ways. A first near infrared illuminator based on the use of conductively cooled mini-bars was designed, realized and successfully tested during outdoor experimentations. This custom specified stack was then replaced in a second step by an off-the-shelf FAC + SAC micro lensed stack where the brightness was increased by polarization overlapping. The third method still based on a commercial laser diode stack uses a non imaging optical shaping principle resulting in a virtually restacked laser source with enhanced beam parameters. This low cost, efficient and low alignment sensitivity beam shaping method allows obtaining a compact and high performance laser diode illuminator for long range active imaging applications. The three methods are presented and compared in this paper.
{"title":"Comparison of three methods reducing the beam parameter product of a laser diode stack for long range laser illumination applications","authors":"Y. Lutz, J. Poyet, N. Metzger","doi":"10.1117/12.2028635","DOIUrl":"https://doi.org/10.1117/12.2028635","url":null,"abstract":"Laser diode stacks are interesting laser sources for active imaging illuminators. They allow the accumulation of large amounts of energy in multi-pulse mode, which is well suited for long-range image recording. Even when laser diode stacks are equipped with fast-axis collimation (FAC) and slow-axis collimation (SAC) microlenses, their beam parameter product (BPP) are not compatible with a direct use in highly efficient and compact illuminators. This is particularly true when narrow divergences are required such as for long range applications. To overcome these difficulties, we conducted investigations in three different ways. A first near infrared illuminator based on the use of conductively cooled mini-bars was designed, realized and successfully tested during outdoor experimentations. This custom specified stack was then replaced in a second step by an off-the-shelf FAC + SAC micro lensed stack where the brightness was increased by polarization overlapping. The third method still based on a commercial laser diode stack uses a non imaging optical shaping principle resulting in a virtually restacked laser source with enhanced beam parameters. This low cost, efficient and low alignment sensitivity beam shaping method allows obtaining a compact and high performance laser diode illuminator for long range active imaging applications. The three methods are presented and compared in this paper.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130865634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this work, the applicability of charge controlled electrostatically tuneable optical filters is investigated. The filters are based on a Fabry-Pérot architecture, fabricated in a bulk micromachining process. Compared to surface micromachined devices, this design opens a path to higher optical performance due to the high planarity and low roughness of substrates but also introduces the drawback of acceleration sensitivity because of a moving mass. The common way of tuning those electrostatic actuators by applying constant voltages decreases the effective stiffness of the system and thus further increases this sensitivity for large deflections. In addition, the tuning range is limited to one third of the initial electrode spacing due to the pull-in effect. Therefore, designing voltage-controlled electrostatic actuators of such optical filters result in tough tradeoffs between initial electrode spacing, spring stiffness, supply voltage and chip area. In order to overcome the limitation of the tuning range and relax these tradeoffs, controlling the charge instead of voltage by using a switched capacitor amplifier is examined. Experiments have shown that it is possible to obtain a stable relative displacement of up to 60% limited by reflector tipping. Measuring gravity impact confirmed the expected reduced deflection dependency. Thus, it is possible to downsize the initial electrode spacing by 45% and the spring stiffness by 40% while achieving the same optical tuning range and acceleration sensitivity as in voltage mode. However, because of reflector tilting and the associated filter bandwidth degradation, a further tradeoff arises when using relative deflections greater 40 %.
{"title":"Charge control of electrostatically actuated micromechanical infrared Fabry-Pérot filters","authors":"S. Lehmann, M. Ebermann, N. Neumann","doi":"10.1117/12.2029302","DOIUrl":"https://doi.org/10.1117/12.2029302","url":null,"abstract":"In this work, the applicability of charge controlled electrostatically tuneable optical filters is investigated. The filters are based on a Fabry-Pérot architecture, fabricated in a bulk micromachining process. Compared to surface micromachined devices, this design opens a path to higher optical performance due to the high planarity and low roughness of substrates but also introduces the drawback of acceleration sensitivity because of a moving mass. The common way of tuning those electrostatic actuators by applying constant voltages decreases the effective stiffness of the system and thus further increases this sensitivity for large deflections. In addition, the tuning range is limited to one third of the initial electrode spacing due to the pull-in effect. Therefore, designing voltage-controlled electrostatic actuators of such optical filters result in tough tradeoffs between initial electrode spacing, spring stiffness, supply voltage and chip area. In order to overcome the limitation of the tuning range and relax these tradeoffs, controlling the charge instead of voltage by using a switched capacitor amplifier is examined. Experiments have shown that it is possible to obtain a stable relative displacement of up to 60% limited by reflector tipping. Measuring gravity impact confirmed the expected reduced deflection dependency. Thus, it is possible to downsize the initial electrode spacing by 45% and the spring stiffness by 40% while achieving the same optical tuning range and acceleration sensitivity as in voltage mode. However, because of reflector tilting and the associated filter bandwidth degradation, a further tradeoff arises when using relative deflections greater 40 %.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115729860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A reliability-based structural design method for infrared cryostat is put forward to obtain a design result with a quantitative reliability index. In this method, the reliability analysis is performed by integrating the finite element software ANSYS (functioning as the deterministic analyzer) with the probabilistic engineering analysis software NESSUS (functioning as the probabilistic analyzer), in which design parameters are treated as random variables. The probability of failure and probabilistic sensitivity level of design parameters are calculated, which would provide a quantitative judgment about whether there should be a redesign and which parameters should be modified in the redesign. As an example to illustrate this method, the IR focal plane displacement induced by random vibration has been analyzed in this paper. The probability of the focal plane displacement value exceeding a critical value is calculated and the focal plane stability reliability level has been increased from 82% to 99.9999%. The method can be widely applicable in the fields where uncertainty is assumed to have a significant impact on the structural response.
{"title":"Reliability-based structural design for infrared cryostat","authors":"Songlin Yu, Chunsheng Wang","doi":"10.1117/12.2026649","DOIUrl":"https://doi.org/10.1117/12.2026649","url":null,"abstract":"A reliability-based structural design method for infrared cryostat is put forward to obtain a design result with a quantitative reliability index. In this method, the reliability analysis is performed by integrating the finite element software ANSYS (functioning as the deterministic analyzer) with the probabilistic engineering analysis software NESSUS (functioning as the probabilistic analyzer), in which design parameters are treated as random variables. The probability of failure and probabilistic sensitivity level of design parameters are calculated, which would provide a quantitative judgment about whether there should be a redesign and which parameters should be modified in the redesign. As an example to illustrate this method, the IR focal plane displacement induced by random vibration has been analyzed in this paper. The probability of the focal plane displacement value exceeding a critical value is calculated and the focal plane stability reliability level has been increased from 82% to 99.9999%. The method can be widely applicable in the fields where uncertainty is assumed to have a significant impact on the structural response.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"8896 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129668606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ann-Kristin Grosselfinger, David Münch, W. Hübner, Michael Arens
Autonomously operating semi-stationary multi-camera components are the core modules of ad-hoc multi-view methods. On the one hand a situation recognition system needs overview of an entire scene, as given by a wide-angle camera, and on the other hand a close-up view from e.g. an active pan-tilt-zoom (PTZ) camera of interesting agents is required to further increase the information to e.g. identify those agents. To configure such a system we set the field of view (FOV) of the overview-camera in correspondence to the motor configuration of a PTZ camera. Images are captured from a uniformly moving PTZ camera until the entire field of view of the master camera is covered. Along the way, a lookup table (LUT) of motor coordinates of the PTZ camera and image coordinates in the master camera is generated. To match each pair of images, features (SIFT, SURF, ORB, STAR, FAST, MSER, BRISK, FREAK) are detected, selected by nearest neighbor distance ratio (NNDR), and matched. A homography is estimated to transform the PTZ image to the master image. With that information comprehensive LUTs are calculated via barycentric coordinates and stored for every pixel of the master image. In this paper the robustness, accuracy, and runtime are quantitatively evaluated for different features.
{"title":"Feature-based automatic configuration of semi-stationary multi-camera components","authors":"Ann-Kristin Grosselfinger, David Münch, W. Hübner, Michael Arens","doi":"10.1117/12.2027311","DOIUrl":"https://doi.org/10.1117/12.2027311","url":null,"abstract":"Autonomously operating semi-stationary multi-camera components are the core modules of ad-hoc multi-view methods. On the one hand a situation recognition system needs overview of an entire scene, as given by a wide-angle camera, and on the other hand a close-up view from e.g. an active pan-tilt-zoom (PTZ) camera of interesting agents is required to further increase the information to e.g. identify those agents. To configure such a system we set the field of view (FOV) of the overview-camera in correspondence to the motor configuration of a PTZ camera. Images are captured from a uniformly moving PTZ camera until the entire field of view of the master camera is covered. Along the way, a lookup table (LUT) of motor coordinates of the PTZ camera and image coordinates in the master camera is generated. To match each pair of images, features (SIFT, SURF, ORB, STAR, FAST, MSER, BRISK, FREAK) are detected, selected by nearest neighbor distance ratio (NNDR), and matched. A homography is estimated to transform the PTZ image to the master image. With that information comprehensive LUTs are calculated via barycentric coordinates and stored for every pixel of the master image. In this paper the robustness, accuracy, and runtime are quantitatively evaluated for different features.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127641736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Thermal imagers and used therein infrared array sensors are subject to calibration procedure and evaluation of their voltage sensitivity on incident radiation during manufacturing process. The calibration procedure is especially important in so-called radiometric cameras, where accurate radiometric quantities, given in physical units, are of concern. Even though non-radiometric cameras are not expected to stand up to such elevated standards, it is still important, that the image faithfully represents temperature variations across the scene. Detectors used in thermal camera are illuminated by infrared radiation transmitted through an infrared transmitting optical system. Often an optical system, when exposed to uniform Lambertian source forms a non-uniform irradiation distribution in its image plane. In order to be able to carry out an accurate non-uniformity correction it is essential to correctly predict irradiation distribution from a uniform source. In the article a non-uniformity correction method has been presented, that takes into account optical system’s radiometry. Predictions of the irradiation distribution have been confronted with measured irradiance values. Presented radiometric model allows fast and accurate non-uniformity correction to be carried out.
{"title":"Determination of the microbolometric FPA's responsivity with imaging system's radiometric considerations","authors":"S. Gogler, G. Bieszczad, M. Krupiński","doi":"10.1117/12.2028859","DOIUrl":"https://doi.org/10.1117/12.2028859","url":null,"abstract":"Thermal imagers and used therein infrared array sensors are subject to calibration procedure and evaluation of their voltage sensitivity on incident radiation during manufacturing process. The calibration procedure is especially important in so-called radiometric cameras, where accurate radiometric quantities, given in physical units, are of concern. Even though non-radiometric cameras are not expected to stand up to such elevated standards, it is still important, that the image faithfully represents temperature variations across the scene. Detectors used in thermal camera are illuminated by infrared radiation transmitted through an infrared transmitting optical system. Often an optical system, when exposed to uniform Lambertian source forms a non-uniform irradiation distribution in its image plane. In order to be able to carry out an accurate non-uniformity correction it is essential to correctly predict irradiation distribution from a uniform source. In the article a non-uniformity correction method has been presented, that takes into account optical system’s radiometry. Predictions of the irradiation distribution have been confronted with measured irradiance values. Presented radiometric model allows fast and accurate non-uniformity correction to be carried out.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115860126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Materials and Components for Missiles Innovation and Technology Partnership (ITP) is a research programme supporting research for guided weapons at Technology Readiness Levels 1 to 4. The Anglo-French initiative is supported by the DGA and the MoD, with matched funding from industry. A major objective is to foster projects which partner UK and French universities, SMEs and larger companies. The first projects started in January 2008 and the first phase completed in spring 2013. Providing funding is secured, the next phase of the programme is due to start later in 2013. Selex ES leads Domain 3 of the MCM-ITP which develops Electro-Optic sensor technology. In collaboration with DGA, MoD and MBDA, the prime contractor, we identified 4 key objectives for the first ITP phase and focussed resources on achieving these. The objectives were to enable better imagery, address operationally stressing scenarios, provide low overall through life cost and improve active and semi-active sensors Nine normal projects and one ITP innovation fund project have been supported within the domain. The technology providers have included 3 SMEs and 8 research centres from both the United Kingdom and France. Highlights of the projects are included. An outline of the priorities for the domain for the new phase ise provided and we encourage organisations with suitable technology to contact us to get involved.
{"title":"Results from the electro-optic sensors domain of the materials and components for missiles innovation and technology partnership (phase 1)","authors":"M. Bray, Robert A. Shears","doi":"10.1117/12.2028735","DOIUrl":"https://doi.org/10.1117/12.2028735","url":null,"abstract":"The Materials and Components for Missiles Innovation and Technology Partnership (ITP) is a research programme supporting research for guided weapons at Technology Readiness Levels 1 to 4. The Anglo-French initiative is supported by the DGA and the MoD, with matched funding from industry. A major objective is to foster projects which partner UK and French universities, SMEs and larger companies. The first projects started in January 2008 and the first phase completed in spring 2013. Providing funding is secured, the next phase of the programme is due to start later in 2013. Selex ES leads Domain 3 of the MCM-ITP which develops Electro-Optic sensor technology. In collaboration with DGA, MoD and MBDA, the prime contractor, we identified 4 key objectives for the first ITP phase and focussed resources on achieving these. The objectives were to enable better imagery, address operationally stressing scenarios, provide low overall through life cost and improve active and semi-active sensors Nine normal projects and one ITP innovation fund project have been supported within the domain. The technology providers have included 3 SMEs and 8 research centres from both the United Kingdom and France. Highlights of the projects are included. An outline of the priorities for the domain for the new phase ise provided and we encourage organisations with suitable technology to contact us to get involved.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"8896 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130713363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fritjof Büttner, J. Hagemann, Mike Wellhausen, S. Funke, C. Lenth, F. Rotter, Lars Gundrum, U. Plachetka, C. Moormann, M. Strube, A. Walte, H. Wackerbarth
A detector which can detect a broad range of explosives without false alarms is urgently needed. Vibrational spectroscopy provides specific spectral information about molecules enabling the identification of analytes by their “fingerprint” spectra. The low detection limit caused by the inherent weak Raman process can be increased by the Surface Enhanced Raman (SER) effect. This is particularly attractive because it combines low detection limits with high information content for establishing molecular identity. Based on SER spectroscopy we have constructed a modular detection system. Here, we want to show a combination of SER spectroscopy and chemometrics to distinguish between chemically similar substances. Such an approach will finally reduce the false alarm rate. It is still a challenge to determine the limit of detection of the analyte on a SER substrate or its enhancement factor. For physisorbed molecules we have applied a novel approach. By this approach the performance of plasmonic substrates and Surface Enhanced Raman Scattering (SERS) enhancement of explosives can be evaluated. Moreover, novel nanostructured substrates for surface enhanced IR absorption (SEIRA) spectroscopy will be presented. The enhancement factor and a limit of detection are estimated.
{"title":"Surface enhanced vibrational spectroscopy for the detection of explosives","authors":"Fritjof Büttner, J. Hagemann, Mike Wellhausen, S. Funke, C. Lenth, F. Rotter, Lars Gundrum, U. Plachetka, C. Moormann, M. Strube, A. Walte, H. Wackerbarth","doi":"10.1117/12.2028736","DOIUrl":"https://doi.org/10.1117/12.2028736","url":null,"abstract":"A detector which can detect a broad range of explosives without false alarms is urgently needed. Vibrational spectroscopy provides specific spectral information about molecules enabling the identification of analytes by their “fingerprint” spectra. The low detection limit caused by the inherent weak Raman process can be increased by the Surface Enhanced Raman (SER) effect. This is particularly attractive because it combines low detection limits with high information content for establishing molecular identity. Based on SER spectroscopy we have constructed a modular detection system. Here, we want to show a combination of SER spectroscopy and chemometrics to distinguish between chemically similar substances. Such an approach will finally reduce the false alarm rate. It is still a challenge to determine the limit of detection of the analyte on a SER substrate or its enhancement factor. For physisorbed molecules we have applied a novel approach. By this approach the performance of plasmonic substrates and Surface Enhanced Raman Scattering (SERS) enhancement of explosives can be evaluated. Moreover, novel nanostructured substrates for surface enhanced IR absorption (SEIRA) spectroscopy will be presented. The enhancement factor and a limit of detection are estimated.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115164418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yongqian Li, Yongjun Guo, L. Su, Binbin Wang, Zheng Xu, Zili Zhou
Optical antennas hold great promise for increasing the efficiency of photovoltaics, light-emitting devices, and optical sensors1. This paper discusses one strategy to achieve frequency selective detection at mid-infrared region, which utilize the plasmonic absorption nanoantenna. The infrared devices realized by such nanoantenna array have merits such as more flexibility of frequency selectivity, and its highlights of polarization properties, which will develop increased functionality for next generation focal plane arrays2. We investigated one example of such nanoantenna devices to tune its plasmonic resonance for achieving frequency selectivity and polarization properties. We also demonstrated its multiplex band absorption, and one tactics to broaden its absorption spectrum. The broad infrared sensitivity of nanoantenna devices would enable multiplex bands infrared imaging detectors. The optical properties of such examples are simulated and measurement which shows perfect absorption in certainty frequency-band. By exploiting nanoantenna as light-harvesting and carrier generation element, plasmonic absorption nanoantenna devices would realize both polarization- and wavelength-selective detection, which would overcome the band gap limitations of existing semiconducting materials.
{"title":"Plasmonic absorption nanoantenna for frequency selective mid-infrared detection","authors":"Yongqian Li, Yongjun Guo, L. Su, Binbin Wang, Zheng Xu, Zili Zhou","doi":"10.1117/12.2031060","DOIUrl":"https://doi.org/10.1117/12.2031060","url":null,"abstract":"Optical antennas hold great promise for increasing the efficiency of photovoltaics, light-emitting devices, and optical sensors1. This paper discusses one strategy to achieve frequency selective detection at mid-infrared region, which utilize the plasmonic absorption nanoantenna. The infrared devices realized by such nanoantenna array have merits such as more flexibility of frequency selectivity, and its highlights of polarization properties, which will develop increased functionality for next generation focal plane arrays2. We investigated one example of such nanoantenna devices to tune its plasmonic resonance for achieving frequency selectivity and polarization properties. We also demonstrated its multiplex band absorption, and one tactics to broaden its absorption spectrum. The broad infrared sensitivity of nanoantenna devices would enable multiplex bands infrared imaging detectors. The optical properties of such examples are simulated and measurement which shows perfect absorption in certainty frequency-band. By exploiting nanoantenna as light-harvesting and carrier generation element, plasmonic absorption nanoantenna devices would realize both polarization- and wavelength-selective detection, which would overcome the band gap limitations of existing semiconducting materials.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114848705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Optical communications in the blue-green waveband offers the attractive prospect of secure, high-bandwidth communications for a variety of civil and military applications. Recent developments in blue-green lasers, spectral filters, and detection technologies are reviewed and their potential for compact, affordable systems is discussed.
{"title":"Technologies for blue-green underwater optical communications","authors":"R. Hollins, A. Rudge, S. Bennett","doi":"10.1117/12.2034427","DOIUrl":"https://doi.org/10.1117/12.2034427","url":null,"abstract":"Optical communications in the blue-green waveband offers the attractive prospect of secure, high-bandwidth communications for a variety of civil and military applications. Recent developments in blue-green lasers, spectral filters, and detection technologies are reviewed and their potential for compact, affordable systems is discussed.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"295 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122275256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jie Xu, Shanping Jiang, Q. Xiao, Pengsong Zhang, Linhua Yang, Hongsong Li, Y. Xiang
A large-scale in-door illumination simulating system was designed and developed by Beijing Institute of Spacecraft Environment Engineering for solar illumination test requirements of a deep-space sensor. Metallic Halide Lamps and Tungsten Halogen Lamps with good accuracy and small collimating angle lanterns, which are high-power and good-match with sunlight, distribute on the wall of the laboratory in order to make good uniformity in an area of 20m×20m. Design results show that, firstly, total average radiation intensity is 400.4W/m2. Secondly, intensity are 48.5W/m2 in 600nm～700nm and 5.1W/m2 in 965nm～995nm. Thirdly, incident angle of the system range from 15° to 45°. Fourthly, uniformity with 15°, 30° and 45° are ±12.4%, ±8.1% and ±14.9% respectively. Finally, shadow profile in the area is clear. The results of acceptance test match the design results very well and meet the requirements totally. The system has been used in laboratory test of the detector successfully.
{"title":"Optical design of a large-scale in-door illumination simulating system","authors":"Jie Xu, Shanping Jiang, Q. Xiao, Pengsong Zhang, Linhua Yang, Hongsong Li, Y. Xiang","doi":"10.1117/12.2027353","DOIUrl":"https://doi.org/10.1117/12.2027353","url":null,"abstract":"A large-scale in-door illumination simulating system was designed and developed by Beijing Institute of Spacecraft Environment Engineering for solar illumination test requirements of a deep-space sensor. Metallic Halide Lamps and Tungsten Halogen Lamps with good accuracy and small collimating angle lanterns, which are high-power and good-match with sunlight, distribute on the wall of the laboratory in order to make good uniformity in an area of 20m×20m. Design results show that, firstly, total average radiation intensity is 400.4W/m2. Secondly, intensity are 48.5W/m2 in 600nm～700nm and 5.1W/m2 in 965nm～995nm. Thirdly, incident angle of the system range from 15° to 45°. Fourthly, uniformity with 15°, 30° and 45° are ±12.4%, ±8.1% and ±14.9% respectively. Finally, shadow profile in the area is clear. The results of acceptance test match the design results very well and meet the requirements totally. The system has been used in laboratory test of the detector successfully.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":" 360","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113946714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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