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板壳结构的振型测量
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作者 周星德 汪凤泉 《应用科学学报》 CAS CSCD 2001年第2期117-120,共4页
应用 CCD图象传感器的线性积分成象机理 ,将时间平均成象方法与数字图象处理技术相结合提出一种新的动态光测方法 .该法只需被测对象静态参考图象及共振态的时间平均成象即可重建板壳结构的振型信息 ,并具有设备简单。
关键词 光学动测 板壳结构 时间平均成象 振型 工程 线性积分成像机理
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Automatic Recognition Method for Optical Measuring Instruments Based on Machine Vision 被引量:2
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作者 宋乐 林玉池 郝立果 《Transactions of Tianjin University》 EI CAS 2008年第3期202-207,共6页
Based on a comprehensive study of various algorithms, the automatic recognition of traditional ocular optical measuring instruments is realized. Taking a universal tools microscope(UTM) lens view image as an example, ... Based on a comprehensive study of various algorithms, the automatic recognition of traditional ocular optical measuring instruments is realized. Taking a universal tools microscope(UTM) lens view image as an example, a 2-layer automatic recognition model for data reading is established after adopting a series of pre-processing algorithms. This model is an optimal combination of the correlation-based template matching method and a concurrent back propagation(BP) neural network. Multiple complementary feature extraction is used in generating the eigenvectors of the concurrent network. In order to improve fault-tolerance capacity, rotation invariant features based on Zernike moments are extracted from digit characters and a 4-dimensional group of the outline features is also obtained. Moreover, the operating time and reading accuracy can be adjusted dy-namically by setting the threshold value. The experimental result indicates that the newly developed algorithm has optimal recognition precision and working speed. The average reading ratio can achieve 97.23%. The recognition method can automatically obtain the results of optical measuring instruments rapidly and stably without modifying their original structure, which meets the application requirements. 展开更多
关键词 automatic recognition optical measuring instruments template matching neural network
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Surface roughness prediction model in ultrasonic vibration assisted grinding of BK7 optical glass 被引量:9
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作者 ZHAO Pei-yi ZHOU Ming +1 位作者 ZHANG Yuan-jing QIAO Guo-chao 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期277-286,共10页
Pre-knowledge of machined surface roughness is the key to improve whole machining efficiency and meanwhile reduce the expenditure in machining optical glass components.In order to predict the surface roughness in ultr... Pre-knowledge of machined surface roughness is the key to improve whole machining efficiency and meanwhile reduce the expenditure in machining optical glass components.In order to predict the surface roughness in ultrasonic vibration assisted grinding of brittle materials,the surface morphologies of grinding wheel were obtained firstly in the present work,the grinding wheel model was developed and the abrasive trajectories in ultrasonic vibration assisted grinding were also investigated,the theoretical model for surface roughness was developed based on the above analysis.The prediction model was developed by using Gaussian processing regression(GPR)due to the influence of brittle fracture on machined surface roughness.In order to validate both the proposed theoretical and GPR models,32sets of experiments of ultrasonic vibration assisted grinding of BK7optical glass were carried out.Experimental results show that the average relative errors of the theoretical model and GPR prediction model are13.11%and8.12%,respectively.The GPR prediction results can match well with the experimental results. 展开更多
关键词 surface roughness prediction model ultrasonic vibration optical glass GPR regression
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Detection and Ranging System of Flight Aid Lights 被引量:1
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作者 YU Zhi-jing WANG Qiang 《Semiconductor Photonics and Technology》 CAS 2007年第1期20-24,共5页
Dynamic detection based on optics sensors and ranging radars is a new method to detect the luminous intensity of flight aid lights. The optics sensors can get the illumination information of each light, the ranging ra... Dynamic detection based on optics sensors and ranging radars is a new method to detect the luminous intensity of flight aid lights. The optics sensors can get the illumination information of each light, the ranging radar gets the distance information, and then data amalgamation technology is used to compute the luminous intensity of each light. A method to modify the errors of this dynamic detection system is presented. It avoids the accumulation error and measurement carrier’s excursion error by using peak value detection based on optics sensors to estimate the accurate position of each light, then to modify the lights’ lengthways distance information and transverse position information. The performance of the detection and ranging system is validated by some experiments and shown in pictures. 展开更多
关键词 luminous intensity dynamic detection ILLUMINATION optics sensor
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Measurement of Trace Manganese(Ⅱ) by the Catalytic Kinetic Spectrophotometric Method 被引量:2
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作者 JI Hongwei SHA Yuanyuan XIN Huizhen QI Yanxia 《Journal of Ocean University of China》 SCIE CAS 2009年第2期127-132,共6页
A new kinetic spectrophotometric method is developed for the measurement of manganese(Ⅱ) in water. The method is based on the catalytic effect of manganese(Ⅱ) with the oxidation of weak acid brilliant blue dye(RAWL)... A new kinetic spectrophotometric method is developed for the measurement of manganese(Ⅱ) in water. The method is based on the catalytic effect of manganese(Ⅱ) with the oxidation of weak acid brilliant blue dye(RAWL) by KIO4 using the Nitrilo triacetic acid(NTA) as an activation reagent. The optimum conditions obtained are 40 mgL-1 RAWL,1×10-4molL-1 KIO4,2×10-4 molL-1 Nitrilo triacetic acid(NTA),pH = 5.8,the reaction time of 3.00 min and the temperature of 20.0 ℃. Under the optimum conditions,the proposed method allows the measurement of manganese(Ⅱ) in a range of 0-50.0 ng mL-1 and with a detection limit of down to 0.158 ng mL-1. The recovery efficiency in measuring the standard manganese(Ⅱ) solution is in a range of 98.5%-102%,and the RSD is in a range of 0.76%-1.25%. The new method has been successfully applied to the measurement of manganese(Ⅱ) in both fresh water and seawater samples with satisfying results. Moreover,few cations and anions interfere with the measurement of manganese(Ⅱ). Compared with other kinetic catalytic methods and instrumental methods,the proposed method shows fairly good selectivity and sensitivity,low cost,cheapness,low detection limit and rapidity. It can be applied on boats easily. 展开更多
关键词 MANGANESE kinetic-spectrophotometry catalytic effect weak acid brilliant blue dye (RAWL) seawater potassium periodate
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Detection of α_(2u)-globulin in rat pup preputial gland by MALDI-TOF mass spectrometry
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作者 Ponnirul PONMANICKAM Gnanasekaran JEBAMERCY +1 位作者 Govindaraju ARCHUNAN Soundrapandian KANNAN 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第4期296-300,共5页
The α_ 2u-globulin,a soluble protein identified in the urine and preputial gland of adult male rat is reported to be pheromone carrier.The pup preputial gland plays a significant role in chemical communication for mo... The α_ 2u-globulin,a soluble protein identified in the urine and preputial gland of adult male rat is reported to be pheromone carrier.The pup preputial gland plays a significant role in chemical communication for mother-young interaction;however,the presence of a pheromone-carrying protein in the pup preputial gland has not been confirmed.Therefore,the present study was carried out to identify the α_ 2u-globulin in the pup preputial gland by Matrix Assisted Laser Desorption Ionization Time of Flight mass spectrometry(MALDI-TOF).The preputial glands of prepubertal rats were subjected to one-dimensional SDS-PAGE.In-gel trypsin digestion of a 18 kDa band was carried out and analyzed by MALDI-TOF.The results of a MASCOT search showed the presence of α_ 2u-globulin in the 18 kDa band.In contrast to the report of the synthesis of this protein only in adult rats,the identification of this protein in pup preputial gland is significant.The results suggest that synthesis of α_ 2u-globulin in the rat preputial gland starts in the prepubertal stage itself.In prepubertal rats,the preputial gland is a source of pheromone for performing anogenital licking behaviour by the mother rat.Since α_ 2u-globulin belongs to the lipocalin(ligand carrier)family,it might carry the volatile for processing pheromonal communication in mother-pup bonding in rat. 展开更多
关键词 α2u-globulin MALDI-TOF Pheromone carrying protein Pup preputial gland RAT
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Probing Molecular Dynamics with Ultrafast Electron Diffraction
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作者 Zhuo-ran Ma Feng-feng Qi Dao Xiang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第1期15-29,I0011,共16页
Recent progress in ultrafast lasers,ultrafast X-rays and ultrafast electron beams has made it possible to watch the motion of atoms in real time through pumpprobe technique.In this review,we focus on how the molecular... Recent progress in ultrafast lasers,ultrafast X-rays and ultrafast electron beams has made it possible to watch the motion of atoms in real time through pumpprobe technique.In this review,we focus on how the molecular dynamics can be studied with ultrafast electron diffraction where the dynamics is initiated by a pumping laser and then probed by pulsed electron beams.This technique allows one to track the molecular dynamics with femtosecond time resolution and Angstr6m spatial resolution.We present the basic physics and latest development of this technique.Representative applications of ultrafast electron diffraction in studies of laser-induced molecular dynamics are also discussed.This table-top technique is complementary to X-ray free-electron laser and we expect it to have a strong impact in studies of chemical dynamics. 展开更多
关键词 Ultrafast electron diffraction Gas phase PHOTOCHEMISTRY Molecular dynamics PUMP-PROBE
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Application of Tunable Diode Laser Absorption Spectroscopy with Optical Hollow Fiber to Engine Exhaust Gas Measurement
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作者 Akira Adachi Yoshihiro Deguchi Shinichirou Konishi 《Journal of Mechanics Engineering and Automation》 2012年第11期656-662,共7页
In recent years, tighter regulation has been already enforced on harmful substances such as NOx, CO, and particles. Considering the above situation, it is important to monitor controlling factors of engine systems in ... In recent years, tighter regulation has been already enforced on harmful substances such as NOx, CO, and particles. Considering the above situation, it is important to monitor controlling factors of engine systems in order to improve efficiencies of their operations. As to car engines, an increasing concern in environmental issues such as air pollution, global warming and petroleum depletion has helped drive researches into various ways. Laser diagnostics has been applied to measure species concentration in the actual industrial fields. However there are several challenges to proceed in applying laser diagnostics to practical application. Especially stability of the measurement system is one of the most difficult issues. The purpose of this research is the development of a prompt measurement technique which can be applicable to various engine conditions. The Tunable Diode Laser Absorption Spectroscopy (TDLAS) using the hollow fiber has been developed to satisfy above requirements. By using a hollow fiber, misalignment of an optical axis and vulnerability of measurement environment such as vibration can be greatly reduced with sensitive and fast response features. It was demonstrated that this method can be applicable to measure gas compositions in engine exhaust with a range of millisecond response time. A sensitive method using tunable UV diode laser absorption spectroscopy was also discussed to detect NOx in exhausts. 展开更多
关键词 Tunable diode laser absorption spectroscopy optical hollow fiber exhaust gas concentration measurement.
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The Potentially Dangerous Asteroid (99942) Apophis
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作者 Ireneusz Wlodarczyk 《Journal of Earth Science and Engineering》 2014年第6期385-388,共4页
This paper computed the newest impact solutions of the potentially dangerous asteroid (99942) Apophis based on 4,138 optical observations from March 15.10789 UTC (Universal Time Coordinated), 2004 to February 28.0... This paper computed the newest impact solutions of the potentially dangerous asteroid (99942) Apophis based on 4,138 optical observations from March 15.10789 UTC (Universal Time Coordinated), 2004 to February 28.089569 UTC, 2014 and 20 radar observations from January 27, 2005 through March 15, 2013, as of June 20, 2014. Using the freely available the OrbFit software Package, this paper followed its orbit forward in the searching for close approaches with the Earth and possible impacts up to year 2116. With the different A2 non-gravitational parameter in the motion of the asteroid (99942) Apophis, this paper computed possible impact solutions using the JPL DE405 (Jet Propulsion Laboratory Development Ephemeris) and 25 additional massive perturbed asteroids. Additionally, this paper used weighing and selection methods adopted in the OrbFit software as prepared by the NEODyS (Near Earth Objects--Dynamical Side) Team. Moreover, this paper used method of computing the orbit of Apophis taking into account star catalog debiasing and an error model with assumed astrometric errors RMS (root mean square), deduced from the observational material of the given observatories. JPL's Sentry and NEODyS's CLOMMON2, two automatic monitoring systems routinely scanning for possible impacts in the next hundred years. Only for several dangerous asteroids presented results are computed with the non-gravitational parameters. This paper detected possible impacts of the asteroid (99942) Apophis only with the non-gravitational parameter, A2 〉 0. It was appeared that impacts in 2068, 2087, 2105 and in 2111 were possible only when Apophis rotated in prograde direction. 展开更多
关键词 ASTROMETRY minor planets individual asteroids Apophis (99942).
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Study on the Determination of Trace Ni(II) by the Catalytic Kinetic Spectrophotometric Method
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作者 JI Hongwei CAO Hengxia XIN Huizhen LI Shuang 《Journal of Ocean University of China》 SCIE CAS 2010年第1期25-30,共6页
A new kinetic spectrophotometric method has been developed for the determination of trace Ni (Ⅱ in natural water. The method is based on the catalytic effect of Ni (Ⅱ) on the oxidation of weak acid brilliant blue... A new kinetic spectrophotometric method has been developed for the determination of trace Ni (Ⅱ in natural water. The method is based on the catalytic effect of Ni (Ⅱ) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium. The concentration of nickel (Ⅱ) can be determined spectrophotometrically by measuring the decrease of absorbance of RAWL at λ = 626 nm using the fix-time method. The influencing factors are investigated by the orthogonal experimental design. The obtained optimum analytical conditions are: pH = 2.00, CRAWL = 5.00×10^-5 mol·L^-1, c KlO4 = 2.00× 10^-5 mol·L^-1, the reaction time t= 10min and the temperature T = 25 ℃. Under the optimum conditions, the developed method allows the measurement of Ni (Ⅱ) in a range of 0 - 40.0ngmL1. The standard deviation of eleven independent measurements of blank reaction is S = 3.08× 10^-3 and the limit of detection is 2.20ng·mL^-1. The relative standard deviations (RSDs) in six replicate determinations of 5 ngmL-1 and 8 ngmL1 Ni (Ⅱ) are 2.87% and 1.11%, respectively. Moreover, the experiments show few cations and anions can interfere with the measurement of Ni (Ⅱ). The recovery efficiencies of this method are in a range of 97.0%-102.5% in freshwater samples. But there is a decreasing effect, which is about 0.2 times the added Ni (Ⅱ) in seawater medium. After reasonable calibration this processing method is used for the determination of Ni (Ⅱ) in seawater samples successfully. The results show this developed method has high accuracy and precision, high sensitivity, large range of linearity and high speed. The method can, therefore, be employed at room temperature. 展开更多
关键词 Ni(Ⅱ) kinetic-spectrophotometry catalytic effect weak acid brilliant blue dye (RAWL) potassium periodate decreasing effect
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Determination of Trace Vanadium (Ⅴ) in Seawater and Fresh Water by the Catalytic Kinetic Spectrophotometric Method
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作者 JI Hongwei SHA Yuanyuan XIN Huizhen LI Shuang 《Journal of Ocean University of China》 SCIE CAS 2010年第4期343-349,共7页
A new kinetic spectrophotometric method has been developed for the determination of vanadium(V).The method is based on the catalytic effect of vanadium(V)on the oxidation of weak acid brilliant blue dye(RAWL)by ... A new kinetic spectrophotometric method has been developed for the determination of vanadium(V).The method is based on the catalytic effect of vanadium(V)on the oxidation of weak acid brilliant blue dye(RAWL)by KBrO3 using the citric acid as activation reagent.The obtained optimum conditions are:c(RAWL)= 1×10-4 molL-1,c(KBrO3)= 3×10-2 molL-1,c(citric acid)=9×10-3 molL-1,pH = 2.50,the reaction time being 7.0min and the temperature being 25.0℃.Under the optimum conditions,the proposed method allows the determination of vanadium(V)in the range of 0-70.0ng mL-1 and the detection limit is down to 0.407 ng mL-1.For standard vanadium(V)solution determination,the recovery efficiency is in the range of 98.5%-102% and the RSD ranges from 0.76%-1.25%.Moreover,it is demonstrated that most cations and anions do not interfere with the determination of vanadium(V)under the analytical condition.The new method was successfully applied in the determination of vanadium(V)in fresh water and seawater samples with satisfactory results.Vanadium(V)in the seawater samples from Qingdao offshore was determined using the method and the distribution of vanadium(V)was mapped.Compared with other instrumental analytical methods,the proposed method shows good selectivity,sensitivity,simplicity,lower cost and rapidity.It can be employed on shipboard easily. 展开更多
关键词 vanadium(V) kinetic-spectrophotometry catalytic effect seawater
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Lunar project ILOM:application of the analytical theory of Lunar physical libration for the simulation of star observations 被引量:1
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作者 PETROVA Nataliya GUSEV Alexander +4 位作者 PING JinSong IVANOVA Tamara HANADA Hideo KAWANO Nobuyuki SU XiaoLi 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第5期888-891,共4页
This study briefly describes the targets and problems of the future Japanese project In situ Lunar Orientation Measurement(ILOM),which is planned for the year 2017.One of the important parts of the project is to place... This study briefly describes the targets and problems of the future Japanese project In situ Lunar Orientation Measurement(ILOM),which is planned for the year 2017.One of the important parts of the project is to place a small optical telescope on the Lunar surface with the purpose to detect the Lunar physical libration with unprecedented accuracy 0.001 arcsec.At the present stage of research the computer simulation of future observations is going on,aiming to determine the moments of transition of a star through the first meridian and the polar distance of the star.Rotation of the Moon is being calculated under the analytical theory developed in the frame of a theme of the grant.A list of stars brighter than 12 m,whose coordinates are close to the Lunar precession pole motion,was constructed on the basis of several star catalogues.On average,for each moment of observation in the field of view of the telescope(1°) there are approximately 20-25 stars.Analyses of simulated stellar tracks observable from the Lunar surface(in a polar zone) reveal the significant difference from daily parallels of stars in comparison with the Earth.During one Lunar "day" equal 237 terrestrial days,a star moves on a spiral.However,depending on a longitude of a star,these spirals can be untwisted or twisted.In the latter case a star can describe a loop in the sky of the Moon during the period of supervision.Such an unusual astrometric phenomenon combined with the slow rotation of the Moon is compared with the Earth and the fast precession motion of the Lunar pole(in comparison with the precession motion of a terrestrial pole). 展开更多
关键词 ILOM LUNAR physical libration TELESCOPE
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Detecting the intrinsic Baldwin Effect of the optical FeII complex in Luminous Seyfert 1 Galaxy Fairall 9
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作者 HAN XuHui WANG Jing +2 位作者 WEI JianYan YANG DaWei HOU JinLiang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第2期346-354,共9页
We analyze the optical spectra of Fairall 9,a luminous Seyfert 1 galaxy.They are obtained from the AGN Watch program that has monitored this object for 9 months.The flux and variation of the optical FeII complex is me... We analyze the optical spectra of Fairall 9,a luminous Seyfert 1 galaxy.They are obtained from the AGN Watch program that has monitored this object for 9 months.The flux and variation of the optical FeII complex is measured using multi-component profile modeling with FeⅡ templates.A convincing intrinsic Baldwin Effect(BEff) of optical FeⅡ emission blends in Fairall 9 is discovered for the first time.The variation of FeⅡ/Hβ(RFe) in Fairall 9 is obtained.We also detect a marginal anti-correla tion between RFe and the continuum flux in its spectra.This anti-correlation and the relatively broad profile of Hβ in this galaxy support the dichotomy reported by Wang et al.(2005). 展开更多
关键词 active galactic nuclei QUASARS Seyfert galaxies H regions emission lines Fairall 9
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A novel orientation measurement using optical sensor for spherical motor 被引量:10
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作者 XIN JianGuo XIA ChangLiang +1 位作者 LI HongFeng SHI TingNa 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第6期1330-1339,共10页
The measurement of spherical rotor orientation is crucial to the close-loop control of spherical motors. This paper presents a novel method for the measuring of three-degree-of-freedom (DOF) rotor orientation of spher... The measurement of spherical rotor orientation is crucial to the close-loop control of spherical motors. This paper presents a novel method for the measuring of three-degree-of-freedom (DOF) rotor orientation of spherical motors using optical sensors. The spatial orientation of spherical rotor is output in the form of ZXZ Euler angles. Firstly, the structure of the measuring system composed of optical sensors and the patterns on the rotor surface are presented, and the operational principle of recognizing intersection points between the optical ring detectors and the latitude/longitude on the rotor surface is illustrated. The analytical model of input-output characteristic is established for the measuring system of three-DOF rotor orientation. Afterwards, the effect of parameters of the optical ring detectors on the linearity, sensitivity, resolving power and measuring range of the measuring system is analyzed using the analytical model. Finally, the feasibility of the measurement is validated through experiments of prototype measuring system. The analysis is expected to be a basis for the design parameter optimization of the orientation measuring system of a PM spherical motor. 展开更多
关键词 Euler angles optical sensor orientation measurement spherical motor three-DOF
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Adjustable contrast optical target device for test of acquisition of photoelectric theodolite
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作者 SUN XiaoXin SHEN XiangHeng +1 位作者 WANG SuHua YE Lu 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第8期2052-2058,共7页
A new device used to detect the low contrast target acquisition of photoelectric theodolite is designed and its reliability is experimentally demonstrated.The adjustable contrast optical target device,which can simula... A new device used to detect the low contrast target acquisition of photoelectric theodolite is designed and its reliability is experimentally demonstrated.The adjustable contrast optical target device,which can simulate the sky background luminance and a low contrast target,is established.It utilizes a big integrating sphere and a small one to simulate the luminance of the background and target respectively.Importantly,by controlling the luminous flux of the two integrating spheres,the targets and background radiance can be continuously adjustable under the condition of constant color temperature.Thus,the contrast can be controlled continuously in the range of 0%-90% and its stability is better than 1%.The biggest background luminance exceeds 60 W m-2str-1 in the spectral range of 400-800 nm. 展开更多
关键词 photoelectric theodolite adjustable contrast integration sphere collimating lens
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