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Stray Light Analysis and Control of Grating Multistage Diffraction in HRS 期刊论文
Guangxue Xuebao/Acta Optica Sinica, 2019, 卷号: 39, 期号: 6
作者: Y.Li; C.Yang; C.Xue; X.Li; Z.Ma

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Stray light,Diffraction,Diffraction gratings,Heterodyning,Light transmission,Quality control,Spectrometers,Spectroscopy

Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Gu S.; Yan Y.; Xu K.; Jin G.

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Fabrication of high-efficiency ultraviolet blazed gratings by use of direct Ar2-CHF3 ion-beam etching through a rectangular photoresist mask (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2011: Sensor and Micromachined Optical Device Technologies, May 24, 2011 - May 26, 2011, Beijing, China
Tan X.

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In ultraviolet spectroscopy groove irregularity and surface roughness of nanometer magnitude can cause a significant loss of diffraction efficiency. Therefore there is a constant need to improve the diffraction efficiency. A blazed grating can concentrate most of the light intensity into a desired diffraction order it is important to control the groove shape precisely so it is the optimum choice among gratings of different kinds of profile. As the operating wavelength of most UV spectral applications is less than 200 nm especially the blaze angle and the apical angle. We have presented a direct shaping method to fabricate EUV blazed gratings by using an ion-beam mixture of Ar+ and CHF2 +to etch K9 glass with a rectangular photoresist mask. With this method the required blaze angle is small we have succeeded in fabricating well-shaped UV blazed gratings with a 1200 line/mm groove density and 8.54 blaze angles and 1200 line/mm groove density and 11.68 blaze angles and the metrical efficiency is about 81% and 78%. The good performance of the gratings was verified by diffraction efficiency measurements. When one uses the etching model the conditions on the ion-beam grazing incident angle and the CHF3partial pressure should be noted. Besides since the etched groove shape depends on the aspect ratio of the photoresist mask ridge if we wish to fabricate larger gratings with this method we must improve the uniformity of the photoresist mask before ion-beam etching. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

Design of programmable near infrared cold light source (EI CONFERENCE) 会议论文
2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China
Wang R.; Fu Q.; Suo H.; Zhao C.; Wang B.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

In the near infrared spectroscopy detector of Charge-coupled Device requires very high stability for light source. We design the cold light source in the measurement of near infrared spectroscopy. Cold light source consists of high-power op amp OPA549 high current constant current source and proportion integral differential (PID) control algorithm. As is shown in the experimental results the method is better the overshoot is very small the stability is excellent in the process of soft-start. While light intensity was able to meet the requirements of near-infrared instruments to measure. 2011 IEEE.

Research on automatic Hartmann test of membrane mirror (EI CONFERENCE) 会议论文
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
Zhong X.; Jin G.; Liu C.; Zhang P.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

Electrostatic membrane mirror is ultra-lightweight and easy to acquire a large diameter comparing with traditional optical elements so its development and usage is the trend of future large mirrors. In order to research the control method of the static stretching membrane mirror the surface configuration must be tested. However membrane mirror's shape is always changed by variable voltages on the electrodes and the optical properties of membrane materials using in our experiment are poor so it is difficult to test membrane mirror by interferometer and null compensator method. To solve this problem an automatic optical test procedure for membrane mirror is designed based on Hartmann screen method. The optical path includes point light source CCD camera splitter and diffuse transmittance screen. The spots' positions on the diffuse transmittance screen are pictured by CCD camera connected with computer and image segmentation and centroid solving is auto processed. The CCD camera's lens distortion is measured and fixing coefficients are given to eliminate the spots' positions recording error caused by lens distortion. To process the low sampling Hartmann test results Zernike polynomial fitting method is applied to smooth the wave front. So low frequency error of the membrane mirror can be measured then. Errors affecting the test accuracy are also analyzed in this paper. The method proposed in this paper provides a reference for surface shape detection in membrane mirror research. 2010 Copyright SPIE - The International Society for Optical Engineering.

Linearity measurement for image-intensified CCD (EI CONFERENCE) 会议论文
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
Zhao Y.; Zhang L.; Yan F.; Gu Y.; Wan L.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

To the characteristic of the ultraviolet CCD (UV ICCD) technique of the linearity measurement of the UV ICCD camera is studied based on the theory of radiometry. Approach of linearity measurement is discussed and a kind of measurement system of the UV ICCD has been developed based on the method of neutral density filter. It is very important that the transmittance of the filter is independent of the wavelength in the method of neutral density filter. Black metal screen mesh with different transmittance is used in our system and calibration of the filters' transmittance in different working positions has been done. Meanwhile to assure the uniform of the received radiation on the target of the detector at any test points an integrating sphere is placed behind the neutral filter to balance light. The whole measurement system mainly consists of a deuterium lamp with high stabilization the attenuation film with transmission integrating sphere optical guide and electro-shift platform. Auto control is realized via special software during the test. With this instrument the linearity of the UV ICCD was measured. Experimental results show that the nonlinearity of the UV ICCD under fixed-gain is less than 2% and the uncertainty of measurement system is less than 4%. 2010 Copyright SPIE - The International Society for Optical Engineering.

New phase measurement method for laser rangefinder (EI CONFERENCE) 会议论文
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
Sun W.-J.; Sun J.-N.; Bu W.-B.; Meng Z.

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A new phase measurement method is designed and presented by using the technique of signal shifting phase and the technique of signal multiplication for laser rangefinder. The intensity of laser light is modulated by cosine circuit signal at the same time the cosine circuit signal is thansformed sine signal by the shifting phase technique. Two signals mentioned above are multiplied by received signal from the target respectively then being transmitted into signal processor after passing through low band filter respectively. The result of phase-shift between the received signal and sent signal is calculated by means of signal processor and time-counter with double frequency of modulation signal. The proposed system is composed of four units such as control and count unit emitting and receiving unit of laser light signal processing unit and result display unit. The two most advantages of proposed system over others are its ability of proper isolation which reduces crosstalk and its independency thermal drift. Theoretical calculations and experimental results have shown the accuracy better than 2 mm. 2010 Copyright SPIE - The International Society for Optical Engineering.

Carbon content detection methods' research in the AOD furnace (EI CONFERENCE) 会议论文
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Hui M.; Yuguo T.; Fangxiao C.

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In the process of smelting of iron alloy the carbon content has been a most important reference to the control of refining end. This article describes the commonly used off-line detection methods about carbon content of hot metal smelting furnace including chemical analysis and spectrometry and introduces the on-line measurement principle measuring devices and modeling based on the light's intensity value. 2010 IEEE.

The calibration of faint simulation star magnitude based on single photon count technique (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Imaging Detectors and Applications, June 17, 2009 - June 19, 2009, Beijing, China
Gan X.-J.; Guo J.; Xu S.-Y.

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A calibration method of faint star magnitude of the star scene simulation device is proposed in this paper. In the research of simulation star magnitude luminometers and CCD devices are the general calibration devices which are used to measure the illumination intensity and calibrate its magnitude. But if the simulation magnitude is only sixth magnitude its illumination intensity is only 1.010-8 Lux. This illumination intensity level is the lowest illumination intensity that the commercial luminometer can detect. Hence the simulation star magnitude lower than six magnitude cannot be calibrated by luminoters. Likewise CCD devices also need an additive cooler in this case. When the single photon characteristic is presented due to the low luminosity of simulating light sources the simulation star magnitude can be calibrated by detecting its photon flux of radiation with the method of single photon count. In this paper the detection principle of single photon based on a compact designed PMT detecting of the radiation level of simulation star magnitude is advanced. Especially a spectrum match method is proved theoretically to be an effective means for selecting PMT photosensitive type. In the case of the detection object of the simulation star in visible wavelength a analysis indicates that the material of tri-alkali cathode materials its best choice after being compared the Signal-to-Noise of photon detector of several PMT photosensitive materials based on the different spectrum match ratio of different object light sources and different cathode materials. An experiment is employed to show the relationship of control voltage of PMT and its dark counter the relationship of the environment temperature of PMT and its dark counter which proves its only decades of CPS at room temperature. The so low dark counter avoids a bulky cooler and is convenient for installing it on the star scene simulation equipment. Finally in the experiment of calibrating the simulation star magnitudes the ability of its calibration is confirmed to reaches up to 12m meanwhile its calibration error is within 0.2m. 2009 SPIE.

The design of composite optical encoder (EI CONFERENCE) 会议论文
9th International Conference on Electronic Measurement and Instruments, ICEMI 2009, August 16, 2009 - August 19, 2009, Beijing, China
Liang L.; Wan Q.; Qi L.; He J.; Du Y.; Lu X.

收藏 | 浏览/下载：11/0 | 提交时间：2013/03/25

In order to improve minimize volume lighten the weight of Measurement and Control Equipment ??the design of a composite optical encoder is put forward in this paper. The composite encoder can achieve the angle measurement as the absolute encoder and the servocontrol as the increment encoder. Base on the requirement of the Measurement and Control Equipment the Composite code disc and the slot is designed then the precision test is implemented on the composite optical encoder. The experimental result shows that the composite optical encoder not only output the measurement of the angle but also provides speed feedback control signal. It has advantages of small volume light weight which can meet the requirements of Measurement and Control Equipment. 2009 IEEE.

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