Opto-Electronic Engineering
Co-Editors-in-Chief
Xiangang Luo
2017
Volume: 44 Issue 5
33 Article(s)

Dec. 04, 2017
  • Vol. 44 Issue 5 1 (2017)
  • [in Chinese]

    Dec. 04, 2017
  • Vol. 44 Issue 5 473 (2017)
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    Dec. 04, 2017
  • Vol. 44 Issue 5 474 (2017)
  • [in Chinese]

    Dec. 04, 2017
  • Vol. 44 Issue 5 474 (2017)
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    Dec. 04, 2017
  • Vol. 44 Issue 5 474 (2017)
  • [in Chinese]

    Dec. 04, 2017
  • Vol. 44 Issue 5 474 (2017)
  • Wei Yang, Shibin Wu, Lihua Wang, Bin Fan, Xiangang Luo, and Hu Yang

    Microstructure membrane optics using surface microstructure on flat thin film to modulate wave can break through these limitations and become an advanced space optical imaging technology. Through the research and analysis of related technologies at home and abroad, this paper reviewed the advances of the membrane tele-scopes and focused on membrane material, microstructure type and optical system design. The implementation of membrane telescopes involves many interdisciplinary disciplines such as materials, space environment en-gineering, nanofabrication technology, precision machinery binary optics and so on.

    Dec. 04, 2017
  • Vol. 44 Issue 5 475 (2017)
  • Wenli Zhang, Fengchun Tian, Zhenzhen Zhao, Li Zhang, Simon X. Yang, and An Song

    Spatial heterodyne spectroscopy (SHS) has been rapidly developed and widely used in recent years as a new type of super-spectral resolution of spectrum analysis technology. According to the structure and principles of SHS, various kinds of interference and distortion of SHS application system which influence the interferogram are analyzed in this paper and a correction scheme of SHS interferogram for the suppression of the interference is proposed. Experimental results show that the proposed method can correct the interferogram effectively, and make the recovered spectrum reflect the input spectral information well and improve the inversion accuracy of the SHS.

    Dec. 04, 2017
  • Vol. 44 Issue 5 488 (2017)
  • Ping Liao, Cheng Ren, and Xiaoyu Yang

    In order to achieve the high-precision non-contact measurement for tiny displacement, a high-precision dis-placement sensor front-end module is designed based on linear array CCD. An optical lens is designed using the principle of laser triangulation, and the system uses the FPGA to generate the drive timing required for the linear array CCD. The one-dimensional video signal output by CCD is handled to obtain a stable analog signal through the front circuit, and the signal is available for digital circuitry. The system has the characteristics of simple struc-ture, small volume, stable output signal, high resolution and high precision. Experimental tests show that the sensor front-end module outputs are stable with small interference analog signal after calculation, the maximum range is ±15 mm, and the accuracy can reach 20 μm. The system can be widely used in the precise measure-ment of tiny displacement.

    Dec. 04, 2017
  • Vol. 44 Issue 5 498 (2017)
  • Xiaobo Yuan, and Chao Zhang

    Focused on the on-orbit calibration problem of the wide field of view star sensor, a novel calibration model based on vector observations is proposed. The model uses 3 Rodrigues parameters, instead of Euler angles, as the ex-terior parameters to simplify the calculation, and complete the joint solution with intrinsic parameters and third order distortion parameters. Simulation shows that it has a higher accuracy than the traditional model with Euler angles. In case of a standard deviation of 0.05 pixels star point error, the model can still accurately calculate the camera parameters and the angle error after calibration is 0.483 arcsecond, and the mean residual errors are 0.019 pixels in x direction and 0.016 pixels in y direction. Furthermore, the initial parameters are simpler and there is no need to set initial values. Its accuracy is further verified by actual star maps of ZY-3 satellite, and result shows that it can improve the calibration accuracy largely. To further improve the calibration accuracy, higher pre-cision centroid algorithm is recommended in actual applications.

    Dec. 04, 2017
  • Vol. 44 Issue 5 505 (2017)
  • Xingguo Zhang, Tao Han, and Jing Li

    The warship is generally equipped with photoelectric theodolite in carrier-borne aircraft flying test. Due to the low frequency of guidance source signal and disturbance from environment, the performance of the system is re-stricted. We proposed an extrapolation-interpolation method and a three points cut-off method to solve the prob-lem, respectively. To smooth the switch of different guidance sources, we also recommended a gradually track-ing algorithm. All the methods above resolve data filter, interpolation and multi-source problem effectively, which are usually encountered in the guiding photoelectric theodolite on the shipboard. At last, the guidance formulae of moving platform are established based on GPS/INS navigation information.

    Dec. 04, 2017
  • Vol. 44 Issue 5 511 (2017)
  • Hasirden, Zhige Zeng, Haitao Liu, and Hongshen Zhao

    The high flexibility optical processing system based on the industrial robot can process large or complex work-pieces. But the positioning error characteristics of the industrial robot will cause the decrease of positioning ac-curacy during grinding, which leads to a lower processing efficiency and processing precision. This paper studies the method of decreasing positioning error, which is verified by simulation and optical processing experiments: Firstly, the positioning error of the polishing tool that fixed at the end of robot in the working area is measured in real-time by using an API T3 laser tracker, and the errors of dwell points are compensated. The measurement experimental results show that the positioning accuracy of the polishing tool meets the high-precision optical processing requirements with the compensation. The dwell time error and the removal error caused by the posi-tioning error before and after compensation are simulated, and the results show that after compensation, the removal error on 80% full aperture is reduced from 3.68% to 0.90%. At last, through the method of the position error compensation to replan the trajectory, the improvement of the processing efficiency and the accurate con-trol on grinding are verified by polishing experiments.

    Dec. 04, 2017
  • Vol. 44 Issue 5 516 (2017)
  • Tianyang Cao, Haoyuan Cai, Dongming Fang, and Chang Liu

    In order to take advantage of global navigation map for robot self-localization and solve kidnap problem, a robot vision localization system is presented based on graphic content matching. It can make good use of the different objects and their layout in different rooms or corridors to fix robot position, which cannot be disturbed by similar objects. This vision localization system is composed of frames overlap region extraction and overlap region re-building through sub-blocks matching, and the interference caused by points on the wall and mismatching sub-blocks can be deleted. The image distortion can be adjusted to the same before matching. In the experiment, this graphic matching method can match the real-time robot vision with keyframes global map effectively, and find out the most similar keyframe for each vision image and fix robot position exactly. More than 95% robot vi-sion can be matched and position RMSE<0.5 m. Robot can also localize itself effectively when it is kidnapped.rebuilding

    Dec. 04, 2017
  • Vol. 44 Issue 5 523 (2017)
  • Tao Zhou, and Lei Wang

    A novel switching function which replaces the sign function is presented in order to reduce high frequency chat-tering of the sliding model control. The dynamics model of multi-DOF serial robot manipulators is studied. A slid-ing control law with this novel switching function is designed and the asymptotic stability of the sliding model control of robot manipulators is proved. The simulation experiments of the sliding model control of 2-DOF robot manipulators illustrate that two links have higher angular position tracking accuracy and speed tracking accuracy. Moreover, its dynamic response is faster. The sliding model control system with the novel switching function re-duces high frequency chattering effectively compared with the sliding model control system with the sign function. This novel switching function can be used on other sliding model control systems, for instance, the airborne elec-tro-optical stabilized platform and missile guidance.

    Dec. 04, 2017
  • Vol. 44 Issue 5 534 (2017)
  • Lipan Gao, and Baozhen Ge

    The hairline is an important feature of human head. Hairline extraction has great research significance and ap-plication value in face perception systems, ergonomics, plastic surgery, etc. A direct hairline extraction method, which uses 3D head color point cloud, is proposed. First, the point cloud is transformed to a face coordinate sys-tem based on human facial features. Second, extract the boundary points of the dark parts through layering and sorting on the basis of the rgb values’ mutation near the hairline. Last, filter out noise points among the boundary points according to prior knowledge about human face, and fit the hairline with de-noised boundary points. Actual 3D head color point clouds are used to prove the effectiveness of proposed method.

    Dec. 04, 2017
  • Vol. 44 Issue 5 539 (2017)
  • [in Chinese]

    Dec. 04, 2017
  • Vol. 44 Issue 5 548 (2017)
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    Dec. 04, 2017
  • Vol. 44 Issue 5 551 (2017)
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    Dec. 04, 2017
  • Vol. 44 Issue 5 553 (2017)
  • [in Chinese]

    Dec. 04, 2017
  • Vol. 44 Issue 5 554 (2017)
  • Lipan Gao, and Baozhen Ge

    As the hairline is an important feature of human head, hairline extraction has great research significance and wide applications, such as face perception systems, plastic surgery, 3D film and television, facelift game, hair set custom-ization. With the development of 3D point cloud model acquirement technology, the study on the three-dimensional (3D) hairline extraction, which can be used to analyze the characteristics of hairline qualitatively and quantitatively, turns into a research hot gradually. Based on the 3D color point cloud of human head, a direct 3D hairline extraction method is proposed. Firstly, the point cloud is transformed into the face coordinate system which is built on the basis of human facial features. Secondly, the head dark parts, including eyeballs, eyebrows and hair, were extracted based on gray threshold T1which can separate hair color from skin color and was calculated using the Otsu algorithm. Thirdly, the boundary points of the dark parts were picked out. The dark parts were layered based on the Y value and the points in every same layer were sorted in accordance with the X value. For each layer, the difference dj, j+1of X coordinate component between consecutive points pjand pj+1for arbitrary index j was calculated and the two points were selected out if the difference between them was higher than a certain threshold T2. In this way, all layers were visited and the boundary points were obtained. Fourthly, the 3D hairline points were acquired by filtering noise points out. According to the prior knowledge of human face that the locations of the eyeballs and eyebrows are on the front of hairline at the same height of face, the boundary points of eyeballs and eyebrows were deleted and the remaining points were 3D hairline points. Finally, the 3D hairline points were fitted to obtain 3D hairline curve. In order to speed up the fitting procedure, the hairline points were simplified using the method of bounding box which can keep the hairline character mostly, and then 3D points were fitted with the algorithm of three B-spline curve fitting. Some ac-tual 3D color point clouds of human head were used to extract the 3D hairlines. The experimental results show that the method proposed here is proven a feasible and effective method. What’s more, compared with the 2D hairline extraction algorithm, it can get more information of hairline.

    Dec. 04, 2017
  • Vol. 44 Issue 5 555 (2017)
  • Tao Zhou, and Lei Wang

    The high frequency chattering of the sliding model control system affects the control accuracy and increases energy consumption. It perhaps stimulates the uncertainty dynamics with the high frequency and causes the system insta-bility. The control input discontinuity caused by the sign function is the main reason for the high frequency chattering in the sliding model control system. A novel switching function which replaces the sign function is presented in order to reduce high frequency chattering of the sliding model control. It is a special continuous power function in the neighborhood of the origin, which refrains from the high frequency chattering phenomena of the control input. When the absolute value of the error is smaller, the gain in the function is greater. When the absolute value of the error is greater, the gain in the function is smaller. Firstly, the dynamics mathematics model of multi-DOF serial robot manip-ulators with the parameters uncertainties and external disturbance is studied. Secondly, a multi-order sliding control law for robot manipulators with the novel switching function is constructed, and the asymptotic stability of the slid-ing model control system of robot manipulators is proved by using the Lyapunov function. Finally, the sine signal tracking simulation experiments of the sliding model control of 2-DOF robot manipulators with the novel switching function are conducted, which are compared with those of the sliding model control with the sign function. The de-sired angular position signal of link 1 and link 2 is q1d=cos(2Πt) and q2d=sin(2Πt) respectively. The maximum angular position tracking error of link 1 is 0.013° and that of link 2 is 0.0065° besides the original values. The maximum an-gular speed tracking error of link 1 is 0.46 °/s and that of link 2 is 0.45 °/s besides the original values. The experiment results illustrate that two links of robot manipulators obtain higher angular position tracking accuracy and speed tracking accuracy. Moreover, dynamic response of the control system is faster. The sliding model control system with the novel switching function reduces high frequency chattering effectively compared with the sliding model control system with the sign function. So the angular speed of two links has much less high frequency chattering. The novel switching function can reduce high frequency chattering phenomena of the sliding model control system which achieves better tracking performances. This switching function can be used on other sliding model control systems, for instance, the airborne electro-optical stabilized platform, numerical control machine and missile guidance, etc.

    Dec. 04, 2017
  • Vol. 44 Issue 5 556 (2017)
  • Tianyang Cao, Haoyuan Cai, Dongming Fang, and Chang Liu

    Self-localization and mapping is an important and difficult problem for mobile robot. Reliable and low cost solution for this issue would promote the development of robotics industry. A robot vision localization system is presented in this paper, which can take advantage of global keyframes navigation map for robot self-localization. And two common problems for robot self-localization, including solve kidnap problem and similar objects interference, can be solved through this localization system, which could fix robot position by matching with global map according to the graphic content in the robot vision. The core of this system is graphic content matching, and composed by two parts: image overlap region extraction and overlap region rebuilding through sub-blocks matching. This method could match image content effectively. If two frames take some same objects, there would be some overlap regions between them. And the overlap regions between two frames can be obtained by translating and rotating these frames according to their matched feature points on the ceiling firstly. And a special designed ceiling feature point extraction and matching method is presented, and the interference caused by points on the wall and mismatching sub-blocks can be deleted according to the features of ceiling structure. After overlap region extraction, the graphic content matching can be processed in these regions. Through image matching, this localization system can make good use of the different objects and their layout in different rooms or corridors as landmarks. These landmarks can be used to fix robot global position precisely in the large indoor space, which is composed of multi-rooms and corridors. By taking advantage of image content, this vision system could make good use of the different objects in different rooms and cannot be disturbed by similar objects, which is common interference for global indoor environment lo-calization. However, there would be some new interference for graphic content matching. The main interference is image distortion, which is caused by camera angle and robot movement. In order to revise image distortion and lo-calize robot exactly, a graphic content matching method is presented. According to the features of image distortion, this matching method is designed through sub-blocks matching in the overlap regions between two frames. It could calculate the images similarity by adjusting the images to the same distortion. In the experiment, this graphic matching method can match the real-time robot vision with global keyframes map effectively, and find out the most similar keyframe for each vision image and fix robot position exactly. More than 95% robot vision can be matched and position RMSE<0.5 m. Robot can also localize itself effectively when it is kidnapped.

    Dec. 04, 2017
  • Vol. 44 Issue 5 557 (2017)
  • Hasirden, Zhige Zeng, Haitao Liu, and Hongshen Zhao

    With the wide applications of optical systems, the demand for optical components is increasing. In order to meet the requirements of large quantity and low cost production of optical components, the optical manufacturing industry must find out a high-efficient, high-accuracy, economical and practical processing method. After years of develop-ment, many new technologies, such as ion beam, magneto-rheological fluid and air bag, have been produced in op-tical manufacturing. However, these processing equipments are often expensive, and some of these processing equipment cannot process large or complex workpieces because of space limitation. The high flexibility optical pro-cessing system based on the industrial robot, which combined industrial robot technology and computer numerical control technology, can process special optical components. Since the arm-rigid of now available robot is low, the defect of high positioning error in optical process leads to a lower processing efficiency and processing precision. This paper set the optical processing robot as the study object, and the following research works were carried out:1) The positioning error of the polishing tool that fixed at the end of robot in circular flat area of Φ500 mm was measured in real-time by using an API Tracker 3 laser tracker. The spatial positions of dwell points were remeasured after the positioning error compensation. The measurement experimental results show that the positioning error of dwell points was reduced from 1158.3052 μm to 227.8408 μm.2) According to above measurement of the positioning error before and after compensation, the dwell time error and the removal rate error caused by each group were calculated in optical processing simulation. The results show that after compensation, the removal rate error on 80% aperture was reduced from 3.68% to 0.90%.3) A K9 material flat mirror of Φ130 mm was polished uniformly in the polishing experiment. The actual removal rate was obtained by subtracting surface data before and after processing. Based on the above measurements, the position error of dwell points was compensated. After replanning the processing trajectory, the removal rate error was reduced from 53.38 nm to 26.64 nm. The processing accuracy was improved by compensating the positioning error.

    Dec. 04, 2017
  • Vol. 44 Issue 5 558 (2017)
  • Xingguo Zhang, Tao Han, and Jing Li

    In order to accurately measure the trajectory and characteristic points of the carrier borne aircraft during the flight test, the shipborne photoelectric theodolite is adopted. According to the target position information and the video image information measured by the observation system, the solution is obtained in the deck coordinate system for the accurate trajectory of the target. However, due to the influence of the weather, the distance is short and the field of view is small. When the aircraft enters its working area, it is often too late to be tracked. Related research report is relatively small. In order to solve this problem, according to the ship and aircraft equipped with infrared guide, mutu-al guide and guide work, when a target signal appears, primary mirror of theodolite is guided to aim target direction. Once the target runs into the test area, it will be timely captured. The warship is generally equipped with photoelectric theodolite in shipboard plane flying test. Flight test equipment configuration of the aircraft is equipped with a re-al-time GPS system, and the ship is equipped with telemetry system, and therefore the project uses an external guide work.According to the environment caused by theodolite data source interference and low data sending rate, the guid-ance algorithm of moving optoelectronic target under complex environment is proposed to solve the problem of photoelectric theodolite stability guidance. The GPS with three organic loading error cutoff methods is adjusted by extrapolation prediction data interpolation method, incremental tracking algorithm source guide smooth switching and coordinate transformation algorithm. Several algorithms are successfully applied to the project, and achieve good results.In flight test, there are two sources of guidance: airborne GPS data and telemetry data sent by the network. Air-borne GPS positioning system through the wireless data chain under the plane cause the ship affected by the elec-tromagnetic environment and the plane distance. Pose variation and occlusion of wireless data link bandwidth and limited data issued by the noise pollution and low frequency eliminate the coordinate transmission conversion error after using three points method of gross error on the received data of coordinate conversion for the first time. The remote sensing system sends the guide data. The frequency is high, and the data is stable. The threshold method is used to remove the outliers and then participates in the guidance calculation. Aiming at the problem of guidance source signal low frequency and interference, thesis puts forward an extrapolation-interpolation method and a three points cut-off method, respectively. Thesis also puts forward gradually tracking algorithm for the smooth transition of guidance sources. The methods all above resolve effectively data filter, interpolation and multi-source problem which are encountered in the guiding photoelectric theodolite on the shipboard. The last moving base photoelectric equipment guidance formulae are educed based on GPS/INS integrated navigation information.

    Dec. 04, 2017
  • Vol. 44 Issue 5 559 (2017)
  • Xiaobo Yuan, and Chao Zhang

    It is urgent to develop high precision calibration model for wide field of view star sensor. It is hard to calculate the camera parameters precisely by using the traditional methods because of large optical aberration. Focused on the on-orbit calibration problem of the wide field of view star sensor, a novel calibration model based on vector observa-tions is proposed. Rodriguez matrix is introduced into the model, and 3 Rodrigues parameters instead of Euler angles, are represented as the exterior parameters to simplify the calculation. The distortion parameters are extended to third order in order to describe the distortion more precisely. Then a joint calculation of intrinsic parameters, exterior pa-rameters and distortion parameters are completed by the model. The performance of the model is analyzed by sim-ulation star map, and result shows that the model has a higher accuracy than the traditional model with Euler angles. In case of a standard deviation of 0.05 pixels star point error, the model can still accurately calculate the camera parameters, and the angle error after calibration is 0.483 arcsecond, and the mean residual errors are 0.019 pixels in x direction and 0.016 pixels in y direction, respectively. Furthermore, the initial parameters are simpler and there is no need to set initial value, and no precise prior attitude information is needed in the calibration process, which will be of great convenience for the practical applications. Its accuracy is further verified by actual star maps of ZY-3 satellite, and result shows that the statistical deviation of star angle after the calibration is 2.376 arcsecond, and the mean residual errors are 0.257 pixels in x direction and 0.151 pixels in y direction respectively, which improve the calibra-tion accuracy largely. Further research on precision analysis is conducted as well. The main procedure is as bellow: Firstly, the Gaussian white noise with the standard deviation of 0 to 1 pixel by steps of 0.01 pixels is added to the star point position, and then the mean value of precision indexes of 100 experiments is calculated. The result shows that the star extraction precision of actual star map is about 0.20 pixels to 0.33 pixels, and to further improve the calibra-tion accuracy, higher precision centroid algorithm is recommended in actual applications.

    Dec. 04, 2017
  • Vol. 44 Issue 5 560 (2017)
  • Ping Liao, Cheng Ren, and Xiaoyu Yang

    The laser displacement measurement system has great demand in the field of measurement in China, but the do-mestic measurement of displacement equipment are different from foreign products in the miniaturization and per-formance, existing large volume, low accuracy, limit of application environment and other issues. Moreover, the re-search on displacement measurement system based on CCD still remains in the laboratory stage and cannot be manufactured. In order to achieve the high-precision non-contact measurement for tiny displacement, a high-precision displacement sensor front-end module is designed based on linear array CCD. The laser is used as a displacement signal transmission medium. The principles of laser triangulation and "Scheimpflug" theorem are used to design an optical lens. The light spot reflected by the measured surface is focused on the photoelectric sensor. Ac-cording to the structure of linear array CCD and drive timing analyses, the system uses the FPGA to generate the drive pulse timing required for the linear array CCD, and the inverter to improve the driving ability to drive linear ar-ray CCD normally. The CCD pixel outputs the one-dimensional video signal and compensation signal after the spot is illuminated. Differential amplifier circuit and low-pass filter circuit are applied to eliminate the reset pulse crosstalk and high frequency noise interference, and a stable analog signal is output, which is available for digital circuits for high frequency sampling to obtain digital signals. Thereby the size and position of the spot center are obtained through the image processing algorithm. When the measured surface moves, the position of the spot center on the CCD also moves. According to the laser triangulation principle, we can calculate the displacement of the measured surface in the direction of the optical axis. The system has the characteristics of simple structure and small volume. The design of integrated circuit meets the measurement requirements, such as stable output signal, high resolution and high precision. Moreover, the designed optical structure meets the requirements, and linear array CCD driving circuit is simple and applicable, aiming at the front-end acquisition and amplification. Experimental tests show that the sensor front-end module outputs are stable with small interference analog signal after calculation. The maximum range is ±15 mm, and the accuracy can reach 20 μm after image processing. The system can be widely used in the precise measurement of tiny displacement, and has a strong practicality and guidance for engineering design. In the future, the system should be further designed and improved in terms of analog signal acquisition, A/D conversion, digital signal processing and image processing. So that it can make a complete and accurate measurement of the displacement and be suitable for practical applications and the need for production.

    Dec. 04, 2017
  • Vol. 44 Issue 5 561 (2017)
  • Wenli Zhang, Fengchun Tian, Zhenzhen Zhao, Li Zhang, Simon X. Yang, and An Song

    Spatial heterodyne spectroscopy (SHS) is a new spectral analysis technique for super-spectral resolution which is developed rapidly and used widely. At present, common applications include atmospheric microelement detection, atmospheric water vapor detection, laboratory astrophysics observation and other weak target identification. How-ever, in practical applications, there are distortions of the collected interferogram which affect the detection accuracy of the system because of bad splitting effect of beam splitter, contaminated grating surface, unbalanced interferom-eter arms, uneven detector response spectrum, electronic circuit error, the dust in the test environment, test platform instability and other factors. Therefore, the noise removal and interference suppression of the interferogram gener-ated by spatial heterodyne spectroscopy are one of the hot issues in the current academic research. Basic structure and principle of SHS were analyzed in detail and the interference and distortion of SHS application system which could influence the interferogram were analyzed and a correction scheme of SHS interferogram with strong robust-ness was proposed according to the existing interferogram processing scheme. The correction scheme includes noise suppression, baseline removal, flatness correction, apodization, phase correction and so on. Then, the SHS experi-mental platform was constructed by using helium-neon laser and sodium lamp respectively and the collected inter-ferogram was analyzed by the scheme mentioned above. Finally, compared the two restoration spectrums got by the original interferogram and the correction interferogram respectively, it is found that the proposed scheme can not only effectively eliminate the interference information in the interferogram, but also reflect the input spectral infor-mation well and improve the inversion accuracy of the SHS system (The resolution limit error of the experimental platform 1 is 0.0004 mm-1and the resolution limit error of the experimental platform 2 is 0.016 mm-1, indicating that the actual resolution of the platform has good agreement with the theoretical resolution). The effectiveness and su-periority of the scheme are verified. In addition, the proposed correction scheme for interferogram does not impose additional requirements on the application environment and equipment of the system so the scheme has high uni-versality and provides some support for SHS research.

    Dec. 04, 2017
  • Vol. 44 Issue 5 562 (2017)
  • Xiaoguang Li, Haoyu Yu, Yuenkeong Yew, Hongzhong Liu, and Minghui Hong

    Fluorescence has a wide variety of applications, including gemology, mineralogy, medicine, chemical sensing, printing dye, and biological labellings. Detection methods based on spectral analysis techniques are an interesting alternative for performing sensitive, selective and reliable measurements. The application of fluorescence in spectral analysis techniques is fluorescence spectrometry which has been successfully utilized as a basic measurement method to ob-tain the characterization of chemical constituents for food classification, water pollution, bacterial pathogens detec-tion and plant species characterization with minimal sample preparation and relatively low-cost instrumentation. Much effort has been done to improve the performance of the fluorescence spectral analysis devices to increase the precision and speed. Although various methods have been explored to improve the instruments’ design and manu-facture, the portability remains a huge challenge.This paper provides the details regarding the fundamental of a portable optical sensing system to fast detect the fluorescence spectra of the samples. A compact configuration is achieved by integrating a small spectrometer as an optical sensor, a microcontroller for issuing commands, a USB Host Shield for internal communication, a network module for external communication, and a web server for storing database and distributing results. The system can offer real-time detection capability, and the test results can be revealed in a short time and downloaded by users to their laptops, tablets or cellphones anytime and anywhere.The main components of the system include a spectrometer (Ocean Optics), a Microcontroller Board (Arduino), a USB Host Shield (Arduino), a 3G+GPS Shield (3E Gadgets) and a Webserver (Amazon). In working condition, the Arduino microcontroller first initializes the USB650 Spectrometer, through the Arduino USB Host shield. Then it sends commands to the spectrometer to acquire spectra of the sample taken. Through the GPS system, the micro-controller acquires the location of the sample and capture an image of the collected sample using Hayes command sets (AT command). Next, together with the spectra data, the microcontroller sends this information up to the web server through the 3G network using 3G + GPS shield for Arduino. In the final step, the web server categories them and processes the spectra data by linking it to the database. The analyzed results are returned to the web server for users to view from any mobile devices that have web browsers, by logging into the web server.In the experiment, three water samples were analyzed, firstly tea water, secondly sea water from West Coast Park of Singapore, and thirdly laboratory tap water. It is concluded that the tea water emits the strongest fluorescence, followed by sea water, while laboratory tap water has no fluorescence emitted. The fluorescence spectra of three water samples have been detected using our system within a short time, thus validating the system’s effectiveness.

    Dec. 04, 2017
  • Vol. 44 Issue 5 563 (2017)
  • Wei Yang, Shibin Wu, Lihua Wang, Bin Fan, Xiangang Luo, and Hu Yang

    Since optical images can intuitively describe the details of objects and get the rich level information of the scene, the optical imaging system has become one of the key earth observing systems. The higher the resolution of the space optical telescope system is, the more information can be got from ground object and the greater the value of the system is. The system resolution depends mainly on the aperture of the telescopes according to the Rayleigh criterion. While for the traditional refraction and reflection optical systems, increasing the aperture encountered several tech-nical bottlenecks such as the rapidly increasing weight, tight optical tolerances, limits packaging and deploying. Un-der the existing carrying capacities, it is more difficult to launch large reflection telescope than 10 meters even with the best current lightweight mirror designs. To solve these problems, a new lightweight microstructure membrane im-aging technology was proposed. This technology uses surface microstructure on flat thin film to modulate light waves subverted the traditional imaging methods based on Snell principle. The figure tolerance on the thin film with uniform thickness can be greatly reduced than the mirror and the weight could be very light. So the membrane lenses are easy to be packed and deployed. Meanwhile, the microstructure can be quickly manufactured by the nano pro-cessing technology, reducing the manufacturing time and costs. In summary, membrane telescope has the highly potentials to achieve large diameter space-based telescope more than 20 meters. At present, the team of the Mem-brane Optical Imager Real-time Exploitation (MOIRE) program supported by the US Defense Advanced Research Project Agency (DARPA) is the leader at this field. They have got stage results in acquisition of large aperture and homogeneous space optical film materials, fabrication of 5 meters membrane optical elements, development and experimental verification of ground prototype, etc.Through the research and analysis of related technologies at home and abroad, this paper reviewed the advances of the membrane telescopes and focused on membrane material, microstructure type and optical system design. The implementation of membrane telescopes involves many interdisciplinary disciplines such as materials, space envi-ronment engineering, nanofabrication technology, precision machinery, binary optics, and so on. As can be expected, with the research of membrane imaging technology in depth, many new key technologies and difficulties will gush out. Therefore, microstructure membrane telescope has a wide application prospects, at the same time meets new theoretical and technical challenges.

    Dec. 04, 2017
  • Vol. 44 Issue 5 564 (2017)
  • [in Chinese]

    The latest progresses about optical quantum computer were announced by Prof. Pan Jianwei team at University of Science and Technology of China. They have achieved ten photon entanglement, and built a quantum simulator for high-efficiency multiphoton boson sam-pling.Bose sampling can be used for demonstrating quan-tum supremacy. The researchers have developed 9×9 mode multiphoton interferometers with 99% transmis-sion rate and actively demultiplexed single-photon sources based on a quantum dot–micropillar with sim-ultaneously high efficiency, purity and indistinguishabil-ity. The three-photon, four-photon and five-photon Bose samples were tested and verified. The sampling rates were 4.96 kHz, 151 Hz and 4 Hz, respectively, which are over 24000 times faster than previous experiments.This is the first single photon-based quantum photonic machines which are provably faster for the bos-on-sampling task than the early classical computer, lay-ing a foundation for the "quantum supremacy ".

    Dec. 04, 2017
  • Vol. 44 Issue 5 565 (2017)
  • [in Chinese]

    Matesurface has added another dimension to diffractive optics. In 2016, the Capasso team at Harvard University successfully developed a flat lens worked in visible spec-trum based on metasurface, which was named among Science Magazine's top discoveries of 2016. But the matelens could only focus one color at a time.The team reported an achromatic metalens (AML) operating over a continuous bandwidth in the visible in January 2017. The AML requires only a one-step lithog-raphy process with NA = 0.2 and a constant focal length over a continuous range of wavelengths 490 nm~550 nm.The building block of the AML consists of a titanium dioxide nanopillar with a square cross-section tiled on a silicon dioxide thin layer above a metallic mirror. With this approach, the researchers also designed a metalens with reverse chromatic dispersion, where the focal length increases as the wavelength increases.This method can effectively develop new components with desired dispersion in these applications such as im-aging under LED illumination, fluorescence.

    Dec. 04, 2017
  • Vol. 44 Issue 5 565 (2017)
  • [in Chinese]

    Traditional strategies for coloration based on selectively absorbing materials like pigment and dye cannot meet the high-resolution display and imaging requirements. With the recent advances in nanotechnology and nano- optics, tailoring the structure parameters of artificially fabricated nanostructures (such as metamaterials and metasurfaces), renders significant benefits for achieving tunable colorations. Compared with other color genera-tion mechanisms, those structural colors are bright and immune to bleach.Recently, an actively tunable structural color rendering with tensile substrate has been reported in Advanced Optical Materials. In this work, the tensile substrate (e.g., polydimethylsiloxane, PDMS) has been introduced into the conventional plasmonic structures to demonstrate the dynamic tunable structural colors. The proposed structure fabricated via interference on PDMS has been experimentally realized, and it shows that resonance-in-duced colors in the Al-PDMS composite structures can be dynamically tuned from green to fuchsia by stretching the tensile substrate in the macroscopic measurements. Moreover, the further theoretical analysis of the physical mechanism in the proposed structure has been investi-gated. This devised method has potential applications in anticounterfeiting, biometric sensors and mechanics measurement.

    Dec. 04, 2017
  • Vol. 44 Issue 5 565 (2017)
  • [in Chinese]

    Optical add-drop multiplexer (OADM) is a device to add and drop the branch signals in the optical domain , as the core equipment of all optical network.Researchers at the University of Shiraz, Iran, designed a new a two-channel OADM consisting of an self-rolled- up microtube (SRM) that has a parabolic lobe-like pat-tern along the tube’s axial direction, as well as straight silicon waveguides and a 180° waveguide bend. The SRM includes one free-standing part and two legs. The straight waveguides, which are placed close to the SRM along the axial direction, are introduced as the in-put-through and add-drop ports, and the free-standing part of SRM acts as a resonator. The vertical configura-tion of the SRM and waveguides was analyzed for an optimum gap. The OADM has the best performance with the channel spacing of 1.6 nm and the minimum insertion loss value of 1.94 dB.The new OADM is small in size, low in insertion loss, and suitable for integrated circuits, which can be used for chip-level interconnect technologies for optical networks.

    Dec. 04, 2017
  • Vol. 44 Issue 5 565 (2017)
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