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1.
提出用微透镜阵列把半导体激光器阵列光束进行准直的方案.采用单正透镜对圆高斯光束的变换理论研究了微透镜的F数,得出了F数以及最小远场发散角半角值的表达式,对微透镜准直器的设计与制备具有指导意义  相似文献   

2.
设计了一种具有自主知识产权的,实现小光斑、大范围、高速度的激光打标机。采用三维动态聚焦技术,通过计算不同平面,以及不同平面上X、Y方向激光的光程变化,运用计算机对伺服电机的控制,使得伺服电机带动扩束透镜调整扩束透镜和聚集镜头之间的距离,实现聚焦补偿,达到三维动态聚焦校正效果。重点介绍了激光打标机的系统构成,以及基于三维动态聚焦技术的激光打标机的系统设计研究。  相似文献   

3.
Beebe DJ  Moore JS  Bauer JM  Yu Q  Liu RH  Devadoss C  Jo BH 《Nature》2000,404(6778):588-590
Hydrogels have been developed to respond to a wide variety of stimuli, but their use in macroscopic systems has been hindered by slow response times (diffusion being the rate-limiting factor governing the swelling process). However, there are many natural examples of chemically driven actuation that rely on short diffusion paths to produce a rapid response. It is therefore expected that scaling down hydrogel objects to the micrometre scale should greatly improve response times. At these scales, stimuli-responsive hydrogels could enhance the capabilities of microfluidic systems by allowing self-regulated flow control. Here we report the fabrication of active hydrogel components inside microchannels via direct photopatterning of a liquid phase. Our approach greatly simplifies system construction and assembly as the functional components are fabricated in situ, and the stimuli-responsive hydrogel components perform both sensing and actuation functions. We demonstrate significantly improved response times (less than 10 seconds) in hydrogel valves capable of autonomous control of local flow.  相似文献   

4.
双液体变焦透镜受电润湿效应驱动,其焦距的变化完全取决于两种液体之间接触面的变化.通过Yang方程推导得到描述接触面的微分方程并以此分析双液体变焦透镜内导电液体、绝缘液体、容器内壁三者间的物理化学性质对初始接触面形貌及初始特性的影响.利用Matlab结合龙格库塔法以数值解描述双液体变焦透镜的接触面特性,并且结合具体试剂的物理性质在ZEMAX中模拟单透镜成像.最后在实验中对比验证得到,存在密度差的双液体变焦透镜接触面的面型为非球面,且经过接触面形貌调制的双液体变焦透镜拥有更好的边缘成像质量,使得双液体变焦透镜在小型化成像系统中有着巨大的应用前景.  相似文献   

5.
Calcitic microlenses as part of the photoreceptor system in brittlestars   总被引:12,自引:0,他引:12  
Aizenberg J  Tkachenko A  Weiner S  Addadi L  Hendler G 《Nature》2001,412(6849):819-822
Photosensitivity in most echinoderms has been attributed to 'diffuse' dermal receptors. Here we report that certain single calcite crystals used by brittlestars for skeletal construction are also a component of specialized photosensory organs, conceivably with the function of a compound eye. The analysis of arm ossicles in Ophiocoma showed that in light-sensitive species, the periphery of the labyrinthic calcitic skeleton extends into a regular array of spherical microstructures that have a characteristic double-lens design. These structures are absent in light-indifferent species. Photolithographic experiments in which a photoresist film was illuminated through the lens array showed selective exposure of the photoresist under the lens centres. These results provide experimental evidence that the microlenses are optical elements that guide and focus the light inside the tissue. The estimated focal distance (4-7 micrometer below the lenses) coincides with the location of nerve bundles-the presumed primary photoreceptors. The lens array is designed to minimize spherical aberration and birefringence and to detect light from a particular direction. The optical performance is further optimized by phototropic chromatophores that regulate the dose of illumination reaching the receptors. These structures represent an example of a multifunctional biomaterial that fulfills both mechanical and optical functions.  相似文献   

6.
As an important optical constant of optical properties for spectacle lens,the refractive index measurement is studied using V prism refractometer. In the experiment,according to various factors inducing measurement error,the experimental results are analyzed,which include right angle deviation,contact liquid,curvature,and focusing accuracy. The study results show that focusing accuracy is the most important factor of influence for measurement,consists of contact liquid wettability,sample shape,and effective width of light transmission. In addition,the refractive index measurement is less affected by angle deviation of sample and the refractive index deviation of contact liquid. On the basis of the experimental data analysis,it is possible to relax the deviation of right angle of the sample to 1' or 2'.  相似文献   

7.
分析了遥感卫星多镜头多光谱相机中影响光学配准的主要因素,进行了配准误差的分配与设计,并针对配准中的两个关键因素——焦距一致性和结构稳定性进行了分析,采用像高测量法调整焦距的一致性,通过增加系统刚度、改进系统的连接方式以及采取热控措施等解决结构稳定性问题.试验表明:所采取的措施有效地保证了多镜头相机的光学配准,确保了遥感相机的实际应用。  相似文献   

8.
紫外衍射微透镜阵列的设计与制备   总被引:1,自引:0,他引:1  
通过研究互相关联的光学和工艺参数,用标量衍射理论设计了用于128×1日盲型紫外探测器的衍射微透镜阵列,其工作中心波长为400 nm,单元透镜F数为.f/5,f为焦距.采用组合多层镀膜和剥离的工艺方法制备微透镜阵列,对工艺流程和制备误差进行了分析,对制备出的128×1的衍射微透镜阵列的光学性能进行测量和分析.实验结果表明,衍射微透镜阵列的衍射效率为87%.制备误差主要来自对准误差和线宽误差.紫外衍射微透镜阵列的整体性能满足了微透镜阵列与紫外焦平面阵列的单片集成要求.  相似文献   

9.
应用CCD和液晶图形发生器的光学多参数综合测试技术研究   总被引:2,自引:0,他引:2  
研究CCD摄像器件和图像处理技术在光电自动化测试中的应用.在采用CCD摄像机、LCD图形发生器和数字图像处理技术的基础上,讨论光学多参数测量新方法及其测量系统,实现了焦距、视放大率、调制传递函数以及视差等参数的测量,并着重论述了光电自动定焦在光学参数测量中的应用.实验证实,该类光学参数测量方法比传统人工目视测量更客观、更准确,测量效率更高,可逐渐取代部分传统目视测量方法.  相似文献   

10.
分析了基于4F光学系统的透镜FT、IFT变换光学的数学表述,指出其参数所表征的物理意义;据此提出利用若干等焦距透镜建立变换光学频谱特征分析实验的构思,利用CCD件和计算机进行采样、分析,阐述d0试件几何孔径等因素对其变换光学频谱特征的影响.  相似文献   

11.
大口径长焦距光学元件的测量一直没有好的解决办法,现利用激光共焦组合焦距测量原理对光学元件进行测量。由于焦点之间的间距值误差传递系数最高,所以要对定焦间距进行准确定焦。对包括被测超长焦距的透镜和未包括超长焦距透镜的激光共焦系统进行两次精确定焦,通过测量两定焦焦点位置之间的距离来获得定焦间距;并在不同的环境下反复测量,以观察环境对于测量精度的影响。通过测量结果可以知道,利用有机玻璃框隔离时测量精度更高,标准差可以达到0.005 4。  相似文献   

12.
为了研究旋转抛物面薄透镜组的光心,首先讨论了单个抛物面薄透镜的光心,在此基础上,根据等效光学系统理论,对旋转抛物面薄透镜组的光心定义、性质和位置进行了详细的探讨和研究,发现旋转抛物面薄透镜组的光心位置取决于两抛物面薄透镜的间距、抛物面的形状、两透镜材料及其周围介质的折射率,最后讨论了空气中旋转抛物面薄透镜组在几种特殊情况下的光心位置.  相似文献   

13.
聚合物微透镜阵列的光学性能测试   总被引:1,自引:0,他引:1  
本文测试了用按需滴定技术制备的聚合物折射微透镜阵列的焦距、透光性、表面粗糙度、波象差、阵列均匀性等参数,并分析了折射型微透镜阵列的光学特性。测试结果表明,用这种方法制备的微透镜阵列具有很好的光学性能和几何形状,焦距在8~10范围内。  相似文献   

14.
Loudet JC  Barois P  Poulin P 《Nature》2000,407(6804):611-613
Some binary mixtures exist as a single phase at high temperatures and as two phases at lower temperatures; rapid cooling therefore induces phase separation that proceeds through the initial formation of small particles and subsequent growth and coarsening. In solid and liquid media, this process leads to growing particles with a range of sizes, which eventually separate to form a macroscopically distinct phase. Such behaviour is of particular interest in systems composed of an isotropic fluid and a liquid crystal, where the random distribution of liquid-crystal droplets in an isotropic polymer matrix may give rise to interesting electro-optical properties. Here we report that a binary mixture consisting of an isotropic fluid and a liquid crystal forming the continuous phase does not fully separate into two phases, but self-organizes into highly ordered arrays of monodisperse colloidal droplet chains. We find that the size and spatial organization of the droplets are controlled by the orientational elasticity of the liquid-crystal phase and the defects caused by droplets exceeding a critical size. We expect that our approach to forming monodisperse, spatially ordered droplets in liquid crystals will allow the controlled design of ordered composites that may have useful rheological and optical properties.  相似文献   

15.
许巧平 《河南科学》2013,(11):1860-1862
基于薄透镜焦平面和副光轴的性质,提供了一种用平行光测量透镜焦距的新方法。该方法中的入射光平行于待测透镜的副光轴而非主光轴。该方法的利用可以加深对薄透镜主光轴、副光轴、焦平面等光学概念的理解和应用,进一步理解近轴成像的含义。  相似文献   

16.
热透镜效应是影响激光焊接质量的重要因素之一。本文描述了激光焊接的模式转变规律,实验测定了透镜焦距变化量与激光功率、激光作用时间的关系,研究了热透镜效应对焊接过程及焊缝成形的影响。结果发现,大功率激光焊接时,热透镜效应使聚焦透镜的焦距缩短并可能使焊接过程逐渐偏离预先设计的稳定焊接模式,从而导致焊接过程的不稳定和熔深的剧烈波动。并通过分析热透镜效应引起焊接模式转变的机理,提出了防止这种因热透镜效应引起的不稳定现象的措施。  相似文献   

17.
Containerless treatment of Bi-58.5at%Ga hypermonotecUc alloy is successfully performed with acoustic levitation technique. Under acoustic levitation condition, the second phase (Ga) distributes almost homogeneously in solidification sample, opposite to macrosegregation in solidification sample under conventional condition. Stokes motion of the second liquid droplet (Ga) is significantly restrained under acoustic levitation condition. The analyses indicate that the melt vibration in the gravity direction forced by acoustic field can induce steady flow around the second liquid droplet, which influences droplet shape during its moving upward and consequently restrains Stokes motion velocity of the second liquid droplet.  相似文献   

18.
利用液滴自身的带电来测量液滴粒度分布的测量系统-电荷探针法测量系统已初步研制成功,并在大型搅拌装置上进行了实际测量及其分析。  相似文献   

19.
采用COMSOL Multiphysics 5.5软件构建的模型研究了透镜焦距变化与激光功率变化的关系,利用理论分析设计实验方案并确定热透镜焦距计算公式.通过实验探究了低功率激光作用下的热透镜效应,实现了低功率激光作用下热透镜效应的可视化,测得酱油透镜为热凹透镜;使用刀口法测量激光半径,得到热凹透镜的焦距,实验相对误差为3.6%;以焦距为热透镜效应的强度参照量,得到热透镜效应的强度与光功率呈正相关关系.  相似文献   

20.
对于菲涅尔透镜作为主要聚光器件的高倍聚光光伏模组,应用中通常把多结电池放置于透镜焦平面处,然而光学系统非理想性造成焦平面处的光照非均匀性,会影响三结电池及模组整体的输出特性。本文通过光线追踪模拟和三维三结电池网络模型,分析沿光轴方向不同位置,菲涅尔透镜聚光光照非均匀性的变化,以及对高倍聚光光伏模组的影响机理和优化。结果表明沿光轴填充因子与光照非均匀性有密切关系,沿光轴不同程度的光照非均匀性导致不同程度的横向电流,填充因子随之发生变化,在远离焦平面的位置存在更优的填充因子,提升最大输出功率。实验结果也很好地验证了模拟的结果,本文结论对实际应用中高倍聚光光伏模组的结构优化有参考意义。  相似文献   

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