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1.
An analytical model has been developed and applied to explore the limits in the design of a highly miniaturized planar optical microspectrometer based on an imaging diffraction grating. This design tool has been validated as providing the smallest possible dimensions while maintaining acceptable spectral resolution. The resulting planar spectrometer is composed of two parallel glass plates, which contain all components of the device, including a reflective slit and an imaging diffraction grating. Fabrication is based on microelectromechanical system technology and starts with a single glass wafer; IC-compatible deposition and lithography are applied to realize the parts in aluminum, which makes the microspectrometer highly tolerant for component mismatch. The fabricated spectrometer was mounted directly on top of an image sensor and takes up a volume of only 50 mm(3). The measured spectral resolution of 6 nm (FWHM) in the 100 nm operating wavelength range (600-700 nm) is in agreement with a model calculation. 相似文献
2.
Source-based radiometry requires reliable transfer standards which are easy to handle. For low irradiances in the UV spectral
range, 30 W deuterium lamps are commonly used. However, for the growing field of high UV irradiance applications, new high
power standards are required. Here we report on a Xe-Hg lamp system which has been characterised and improved to match the
high requirements of a working standard. For this purpose, several parameters of the system such as lamp stability, re-ignition
reproducibility, irradiance uniformity and usability have been investigated. Components for the customised light guide-based
output optics have been selected with the help of extensive characterisations. The resulting lamp system can be used for a
high-grade instrument calibration at high UV irradiance levels. 相似文献
3.
TDI CCD相机实验室辐射定标的研究 总被引:2,自引:0,他引:2
TDI CCD相机辐射定标的目的是建立输入辐亮度和探测器数字化输出之间的关系,为相机提供调光参数.本文推导了辐射定标的原理,并针对特定的TDI CCD相机在应用光学国家重点实验室里使用积分球对其进行了基于光谱辐照度灯的辐射定标,标定了TID CCD相机响应的线性度、TDI CCD相机响应分别与增益和级数的关系,根据实验结果我们得到了在不同的辐亮度值下的增益和级数参考值,从而确定了TDI CCD相机的调光参数,并给出了标定的误差和各项误差源的影响. 相似文献
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We present the working characteristics of a continuous UV lamp emitting at λ=206 nm, pumped by a longitudinal glow discharge. The pressure of the working Xe-I2 gas-vapor mixture was within 0.1–10 kPa. The power deposited in the discharge was varied within 10–130 W. The current-voltage characteristics, the emission spectra in a 200–600 nm wavelength range, the line emission intensity as a function of the power deposited in the discharge plasma, and the partial pressure of xenon in the lamp were studied. It is established that the lamp operates in the range of 206–342 nm on a resonance line of iodine at 206 nm and on the bands at 253 nm [XeI(B-X)] and 342 nm [I2(B-X)]. Not less than half of the output UV emission power is concentrated in the bactericidal spectral interval (around λ=206 nm). The total UV emission power of the lamp reaches 6–7 W at an efficiency of ≤5%. 相似文献
6.
紫外辐射计的波长定标及不确定度分析 总被引:3,自引:1,他引:2
限于常规汞灯谱线法波长定标的局限性,构建了紫外辐射计波长定标装置,研究了紫外辐射计波长定标的物理过程和测量链,并对紫外辐射计中臭氧十二个吸收波长进行了光谱定标,通过对定标影响量的分析和计算,得到定标影响量的测量不确定度和波长定标合成标准不确定度,其中波长定标合成标准不确定度为0.026nm,同时通过光学CAD分析和实验验证紫外辐射计的光谱带宽可以达到1.0nm.应用自行构建的紫外波长定标装置较好地完成了紫外辐射计臭氧吸收谱线的定标工作,满足了臭氧反演所需的波长精度要求和光谱带宽要求. 相似文献
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A high-power stationary helium cascade arc has been developed as a standard source for continuum radiation in the VUV spectral range from 65 to 125 nm. The calibration of the VUV system response was based on the calculated and measured continuum radiation of a 2-mmphi pure He arc. Diagnostics of the arc plasma in partial thermal equilibrium yielded the electron density and the temperature that were inserted in the calculations of the continuous radiation. The results were compared with the helium, argon, and krypton radiation lines of a high-current hollow cathode lamp. This lamp was built according to the construction drawings of a hollow cathode, which was calibrated by means of the electron synchrotron radiation at the Physikalisch Technische Bundesanstalt Berlin. 相似文献
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We present the working characteristics of a high-power UV-VUV electric-discharge lamp filled with a working mixture of helium
and iodine vapor (He-I2) at a low pressure (0.1–1.5 kPa) and pumped by a dc glow discharge at a power of 15–200 W. The power of the total output
UV radiation and the main emission peak at λ = 206.2 nm were studied as dependent on the electric power supplied to the glow
discharge and on the partial pressure of helium in the He-I2 mixture. The emission characteristics of the glow discharge plasma were studied in the spectral range from 200 to 350 nm.
In this range, the lamp is operating predominantly on a resonance emission line of excited iodine atoms (λ = 206.2 nm, FWHM
= 0.10–0.12 nm) and on a system of electronic-vibrational bands of excited iodine molecules with the main peak at λ = 342
nm. The contribution of the resonance emission due to excited iodine atoms to the total UV emission from the glow discharge
plasma does not exceed 50%. The optimum partial pressure of helium is within 400–800 Pa. The total UV radiation power of the
lamp operating in the optimum regime reaches 25 W at an efficiency of η ≤15%. 相似文献
11.
A. K. Shuaibov A. I. Dashchenko I. V. Shevera A. A. General 《Technical Physics Letters》2003,29(12):1009-1010
We report on the optimized characteristics of a small-size bactericidal lamp pumped by transverse RF (f=1.76 MHz) discharge, operating on a system of the molecular emission bands of chlorine in a wavelength range of 195–310 nm.
The spectral characteristics of the plasma emission were measured and the intensity of chlorine emission bands were studied
as functions of the total pressure and partial composition of a helium-chlorine mixture. Oscillograms of the pumping current
and output radiation intensity were measured and the total output radiation power was determined. It is established that the
lamp radiates predominantly in a bactericidal wavelength interval on an electron-vibrational transition at 200 nm in Cl2** molecules. The optimum partial pressures of helium and chlorine are 100–300 and 90–120 Pa, respectively. The maximum output
power of UV emission from the side cylindrical surface of the lamp reached 10 W. The lamp can be used in photochemistry, ecology,
genetics, and medicine. 相似文献
12.
Calibrating the wavelength scale of an array spectrometer typically involves measurements of lines at well-known wavelengths from a calibration lamp such as a mercury-argon source. This process is relatively straightforward when the lines are well separated, relative to the bandwidth of the spectrometer. When the spectrometer's bandwidth is large, compared with the distance between calibration wavelengths, it becomes increasingly difficult to accurately locate lines in the calibration spectrum. Even calibrations for instruments with a modest bandwidth of 12 nm can be difficult. Here we present results from a simple approach to improve the accuracy of wavelength calibration for an instrument with a large bandwidth (12 nm, center-to-center pixel spacing 3.3 nm). A monochromator has been used to filter the source so that each calibration line can be measured separately. For ten spectrometers, we were able to achieve accuracy better than 0.12 nm, or 0.09 nm on average; this is less than 3% of the pixel spacing. We anticipate this approach will be useful for improving the accuracy of measurements on array spectrometers and particularly in transferring multivariate calibrations between instruments. 相似文献
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We present a new polarimetric imaging system based on liquid-crystal modulators, a spectrally filtered white-light source, and a CCD camera. The whole Mueller matrix image of the sample is measured in approximately 5 s in the transmission mode. The instrument design, together with an original and easy-to-operate calibration procedure, provides high accuracy over a wide spectral range (500-700 nm). This accuracy has been assessed by measurement of a linear polarizer at different orientations and a thick wedged quartz plate as an example of a partially depolarized retarder. Polarimetric images of a stained hepatic biopsy with significant fibrosis have been taken at several wavelengths. The optical properties of Picrosirius Red stained collagen (diattenuation, retardance, and polarizance) have been measured independently from each other between 500 and 700 nm. 相似文献
15.
Shaw PS Lykke KR Gupta R O'Brian TR Arp U White HH Lucatorto TB Dehmer JL Parr AC 《Applied optics》1999,38(1):18-28
The combination of a cryogenic radiometer and synchrotron radiation enables detector scale realization in spectral regions that are otherwise difficult to access. Cryogenic radiometry is the most accurate primary detector-based standard available to date, and synchrotron radiation gives a unique broadband and continuous spectrum that extends from x ray to far IR. We describe a new cryogenic radiometer-based UV radiometry facility at the Synchrotron Ultraviolet Radiation Facility II at the National Institute of Standards and Technology. The facility is designed to perform a variety of detector and optical materials characterizations. The facility combines a high-throughput, normal incidence monochromator with an absolute cryogenic radiometer optimized for UV measurements to provide absolute radiometric measurements in the spectral range from 125 nm to approximately 320 nm. We discuss results on photodetector characterizations, including absolute spectroradiometric calibration, spatial responsivity mapping, spectroreflectance, and internal quantum efficiency. In addition, such characterizations are used to study UV radiation damage in photodetectors that can shed light on the mechanism of the damage process. Examples are also given for UV optical materials characterization. 相似文献
16.
We describe the concept of a super compact diffractive imaging spectrometer, with optical components a few millimeters across in all dimensions, capable of detecting optical fluorescence spectra within the entire visible spectral range from 400 nm to 700 nm with resolution of the order of 2 nm. In addition, the proposed spectrometer is capable of working simultaneously with multiple, up to 35, independent input optical channels. A specially designed diffractive optical element integrated with a planar optical waveguide is the key component of the proposed device. In the preliminary experimental tests, a uniform waveguide grating with a microlens was used to mimic operation of the diffractive optical element. A microspectrometer with optical components measured below 1 cm in all dimensions covers the spectral range from 450 nm to 650 nm and shows a spectral resolution of 0.5 nm at wavelengths close to 514 nm and 633 nm. 相似文献
17.
Fujikake H Yonai J Sato H Kikuchi H Iino Y Kawakita M Tsuchiya Y Iwashita K Umeda S 《Applied optics》2001,40(14):2275-2281
A color-temperature compensating system with an electrically controllable liquid-crystal filter and a color sensor mounted on a video camera has been developed for color image sensing. The filter contains two guest-host liquid-crystal devices with dichroic dyes that have strong light absorption for shorter-wavelength light; two devices are necessary because of the spectral difference between the sun and an incandescent lamp as light sources. The filter's absorption is continuously controlled by the voltage applied to the filter. Because the filter is driven according to spectral information about the illumination detected by the color sensor, the color balance of the video image to be sensed can be compensated automatically and rapidly. This is especially useful for video image shooting in which a video camera experiences changes in illumination color temperatures. 相似文献
18.
Correia J.H. de Graaf G. Bartek M. Wolffenbuttel R.F. 《IEEE transactions on instrumentation and measurement》2001,50(6):1530-1537
A single-chip CMOS optical microspectrometer containing an array of 16 addressable Fabry-Perot (F-P) etalons (each one with different resonance cavity length), photodetectors, and circuits for readout, multiplexing, and driving a serial bus interface has been fabricated in a standard 1.6-μm CMOS technology (chip area 3.9 × 4.2 mm2 ). The result is a chip that can operate using only four external connections (including Vdd and Vss) covering the optical range of 380-500 nm with FNVHM = 18 nm. Frequency output and serial bus interface allow easy multisensor, multichip interfacing using a microcontroller or a personal computer. Also, stray-light compensation techniques are implemented. Power consumption is 1250 μW at a clock frequency of 1 MHz 相似文献
19.
V. S. Skakun M. I. Lomaev V. F. Tarasenko D. V. Shitts 《Technical Physics Letters》2002,28(11):899-901
A high-power multisection cylindrical exciplex lamp pumped by a glow discharge is created. The energy, temporal, and spectral characteristics of the emission from KrCl* (λ~-222 nm) and XeCl* (λ~308 nm) molecules are studied. The average output UV radiation power is 1.6 kW (for 222 nm) and 1.1 kW (for 308 nm) at a power pumping efficiency of up to 14%. 相似文献
20.
We have studied the performance of polytetrafluoroethylene integrating spheres in the ultraviolet (UV) region with wavelengths as short as 200 nm. Two techniques were used for this study; first, the spectral throughput of an integrating sphere irradiated by a deuterium lamp was analyzed by a monochromator. Second, a UV laser beam was directed into an integrating sphere, and spectrally dispersed laser induced fluorescence was studied. Significant absorption and fluorescence features were observed in the UV region and attributed to the contamination in the integrating sphere. We demonstrate that integrating spheres are easily contaminated by environmental pollutants such as polycyclic aromatic hydrocarbons emitted from engine exhaust. Baking of the contaminated integrating sphere can reverse some but not all of the effects caused by contaminants. The implications for using integrating spheres for UV measurement are discussed. 相似文献