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1.
与红外定焦镜头和红外两档变焦镜头相比,红外连续变焦镜头具有连续可变的视场,可对目标进行连续的跟踪,是未来红外成像技术的发展方向.随着光学冷加工、精密机械加工、镀膜技术等工艺水平的不断进步,以及现代科技的发展要求,红外变焦镜头向高变焦比方向发展,同时还须保持良好的成像和消热差性能.概述了国外各种高变焦比中波红外镜头的结构和设计方法,包括20高变焦比中波红外镜头、30高变焦比中波红外镜头、300高变焦比中波红外镜头,总结了一套高变焦比中波红外镜头设计经验,对国内高变焦比中波红外镜头的应用发展研究有借鉴价值.  相似文献   

2.
20×长波红外变焦光学系统设计   总被引:1,自引:1,他引:0  
针对红外目标探测等军事应用的实际需求,为了扩大对目标的搜索范围,设计了8~12μm红外波段的20×连续变焦光学系统。该系统采用320×240非制冷焦平面红外探测器,在15~300 mm范围内实现连续变焦,F数为2。系统结构简单,仅由6片透镜组成,并仅引入1个非球面校正系统像差。在空间频率为16 lp/mm 处,变焦范围内的 MTF 调制传递函数均在0.45以上,接近衍射极限,像质优良,像面稳定,可用于坦克红外观瞄系统。  相似文献   

3.
随着红外热成像系统的不断发展,对红外光学系统也提出了更高的要求。为了满足红外探测器在军事方面的广泛应用,整机系统对高性能、大变倍的红外连续变焦光学系统的需求日益增强。针对高端中波制冷型640512 凝视焦平面探测器,设计了结构紧凑、性能优良的高清晰大变倍比机械补偿连续变焦光学系统。该系统工作波段为3.7耀4.8m,F 数为4,变倍比为35:1,变焦范围为15~550mm。该系统运用平滑换根理论,实现了超大变倍比的连续变焦光学系统设计,并且采用二次成像以及45反射镜对光路进行U 型折叠,在实现了冷屏效率100%的同时有效控制了该系统的横向和径向尺寸。采用光学设计软件CODE V 进行了仿真计算和像质评价,并绘制了该系统的变焦曲线。设计结果表明,该连续变焦光学系统具有分辨率高、变倍比大、结构紧凑、在全焦距范围内成像质量优良并且变焦轨迹平滑等优点,能够与高性能中波红外探测器匹配用于高端红外热成像系统。  相似文献   

4.
针对近年来得到迅速发展的短波红外成像系统,分析了增加激光主动照明的必要性.目前常用的激光照明匀化方案均匀性均不高,达不到照明成像的要求.提出了连续变焦激光照明系统,使用成像镜头把光纤端面的像直接成像在被照明表面,照明光斑均匀.分析了变焦照明系统的设计理论,设计了25倍变焦的短波红外激光照明系统.该照明系统的光学镜头由3组镜片组成,由凸轮结构实现连续变焦.体积小,结构简单,变焦倍数大.最终实现了2~50°的照明角度连续变化.照明光斑均匀度达到92.7%.进行了野外成像实验,对人员识别距离可达1.2 km.设计的连续变焦激光照明系统对提高短波红外成像系统的夜视能力具有较高的意义.  相似文献   

5.
针对近年来得到迅速发展的短波红外成像系统,分析了增加激光主动照明的必要性.目前常用的激光照明匀化方案均匀性均不高,达不到照明成像的要求.提出了连续变焦激光照明系统,使用成像镜头把光纤端面的像直接成像在被照明表面,照明光斑均匀.分析了变焦照明系统的设计理论,设计了25倍变焦的短波红外激光照明系统.该照明系统的光学镜头由3组镜片组成,由凸轮结构实现连续变焦.体积小,结构简单,变焦倍数大.最终实现了2~50°的照明角度连续变化.照明光斑均匀度达到92.7%.进行了野外成像实验,对人员识别距离可达1.2 km.设计的连续变焦激光照明系统对提高短波红外成像系统的夜视能力具有较高的意义.  相似文献   

6.
制冷型中波红外变焦镜头   总被引:3,自引:0,他引:3  
在分析中波红外变焦镜头的基础上,分别就初始结构选取、冷反射、变焦等方面对中波红外变焦镜头的光学设计进行探讨,设计出实用、能够加工生产装调出来、成像质量优异的制冷型凝视中波红外连续变焦镜头.  相似文献   

7.
邹雨  陈圣义  范超然  李周  唐伯浩 《红外》2021,42(8):7-12
在靶场辐射测量中,红外辐射特性数据被广泛应用于目标红外特性识别和隐身特性评估,在安防与军事领域发挥着不可替代的作用。目标红外辐射特性数据获取需基于系统的辐射定标。对于中、长波测量系统来说,红外辐射定标主要针对定焦系统,而对变焦系统的辐射标定较少。建立了连续变焦系统的红外辐射定标模型,并对1000 mm口径的短波连续变焦系统进行了分析。数据分析结果显示,随着F数的增大,系统的辐射响应增益减小。分析了其对辐射测量的影响。可以看出,该研究具有一定的工程意义。  相似文献   

8.
针对凝视型红外成像告警设备中对场景目标进行大视场广域搜索与小视场精确识别一体化的应用需求,设计了一种基于共心球透镜的大视场高分辨率红外变焦成像系统.该系统采用由多层共心球透镜和可连续变焦的独立次级小相机阵列级联而成的二次成像结构,能够有效实现大视场高分辨率无畸变成像.此外,采用全动变焦设计的独立次级小相机阵列在对搜索到的目标进行探测、识别和跟踪的一体化检测的同时保持像面稳定,实现对成像场景的分区域管理.设计结果表明,该红外成像系统在全变焦范围内的调制传递函数(MTF)曲线均接近衍射极限,且变焦曲线平滑,避免了变焦过程中卡滞、冲击等不利现象的产生,能有效实现大视场监测及小视场识别的功能.  相似文献   

9.
基于红外连续变焦光学系统镜片控制精度的需要,本文从实时性、准确性等方面分析和研究了一种红外连续变焦光学系统中步进电机的加减速控制技术和螺母间隙误差补偿技术。实验结果表明,该连续变焦控制技术有效地提高了红外连续变焦光学系统光学变倍的实时性和准确性。  相似文献   

10.
吴海清  王玮超 《红外技术》2021,43(12):1177-1182
为适应机载光电系统对红外热像仪光学系统小型化、轻量化的要求,采用前端无焦扩展倍镜与后端连续变焦光学系统组合的方式,实现了30~660 mm的22倍连续变焦光学系统。该系统的光学总长为244 mm,总长/最大焦距比为0.37,系统具有光学总长小、变倍比大的特点,适用于远距离目标探测的大型机载光电吊舱系统中。将前端无焦扩展倍镜去掉后,后端连续变焦光学系统可以实现15~330 mm的22倍连续变焦光学系统,该系统的光学总长为138 mm,总长/最大焦距比为0.42,可作为独立的连续变焦系统应用于近距离目标探测的中小型机载光电吊舱系统中。设计结果显示,该系统在两种状态下均成像良好,在探测器对应的特征频率33 1p/mm处,中心视场的MTF值均在0.3附近,接近衍射极限,0.7视场的MTF值均在0.2附近,边缘视场的MTF均在0.15附近,能够满足应用需求。  相似文献   

11.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

12.
In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal (200) (2d = 0.4027 nm) is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line(w), the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line(x), the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines(y), the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line(z) in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line(q) in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution(λ/△ 2) is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.  相似文献   

13.
This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.  相似文献   

14.
An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.  相似文献   

15.
The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO>6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.  相似文献   

16.
This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.  相似文献   

17.
We have fabricated the white organic light-emitting devices (WOLEDs) based on 4,4' -bis(2,2 -diphenyl vinyl)-1,1' - biphenyl (DPVBi) and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene (rubrene). The device structure is ITO/2T-NATA (20 nm)/NPBX (20 nm)/CBP: x%Ir(ppy)3:0.5% rubrene (8 nm)/NPBX (5 nm)/DPVBi (30 nm)/Alq(30 nm)/LiF(0.5 nm)/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris (2-phenylpyridine) iridium [Ir(ppy)3], acts as a yellow light-emitting layer, and N,N' -bis- (1-naphthyl)- N,N' -diphenyl -1, 1' -biphenyl-4,4' -diamine (NPBX) acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir (PPY)3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.  相似文献   

18.
To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.  相似文献   

19.
本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。  相似文献   

20.
We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.  相似文献   

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