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1.
LED功率的不断增大使其逐渐替代传统光源,并广泛用于各种照明光源。在某些室内照明以及道路照明设计中,通常需要借助LED透镜产生矩形光斑从而充分利用光能避免浪费。利用Light Tools软件设计了一种全内反射(total internal reflection,TIR)透镜与特定微型透镜阵列的组合透镜,设置TIR准直透镜透射曲面和全反射曲面为二次曲面,并对其进行准直优化。然后建立单个微型透镜,设置单个矩形微透镜长宽比分别为1∶1、3∶2和4∶3,并将其阵列化。通过改变微型透镜的尺寸以及球面曲率半径进行进一步优化,最后生成与微型透镜长宽比对应的均匀矩形光斑,从而满足不同矩形照明区域的照明需求。  相似文献   

2.
薄壁LED照明依赖丝网印刷的微阵列导光板,但其表面油墨点阵易老化,且微结构很难优化。因此,在导光板表面设计出高斯分布的空间微槽透镜阵列,并采用数控微磨削技术对其进行加工,替代市面丝网印刷的2D微圆阵列。首先,用微光学原理模拟导光板导光效率和出光均匀度,优化微透镜阵列的形状、尺寸和分布。利用金刚石砂轮微尖端在PMMA导光板表面精密磨削出微透镜阵列,检测其导光效率及均匀性。最后,利用微磨削加工的微阵列成型钢模芯开发微透镜阵列的快速热压微成型工艺。微光学分析表明,微槽透镜阵列比微方形透镜阵列和微半球透镜阵列分别提高导光效率6%和15%。而且,微槽透镜阵列变间距高斯分布比等间距分布提高导光效率32%,提高出光均匀度73%。试验结果显示,微磨削可以控制微槽透镜阵列加工的表面质量和形状精度,应用于LED导光板后比丝网印刷的导光板提高导光效率7%和出光均匀度9%。此外,开发3 s的快速热压微成型工艺,可以加工出变间距和变深度的微槽透镜阵列,比丝网印刷的微圆阵列提高照度26%和出光均匀度49%。因此,微空间结构优化的微槽透镜阵列比丝网印刷的2D微圆阵列可附加出更高的微光学应用价值。  相似文献   

3.
LED阵列式紫外固化光源光学系统设计   总被引:7,自引:3,他引:4  
设计了一种新型的LED阵列式紫外固化光源系统,该系统主要包括多路可控恒流源,紫外LED空间阵列及光学系统等,其中紫外LED空间阵列结构提高了光源的辐照度和均匀性。在分析光源结构的基础上,对其光学系统进行了设计,给出了LED空间阵列光学系统的设计方法和设计实例,并利用Light Tools光学仿真软件对其进行了模拟。结果表明:采用该光学设计方法得到的空间阵列辐照系统,其紫外辐照度可达200 mW/cm2,辐照面上光强分布均匀稳定,能够满足紫外光固化过程对光源的指标要求。  相似文献   

4.
LED(Light Emitting Diode,发光二极管)光针灸是一项新兴的光学针灸技术。本文主要针对LED光针灸仪的整体设计及其对裸鼠体表的局部照射刺激效应展开研究。研究内容包括LED光针灸仪的电学、光学以及机械设计,LED光针灸仪对动物穴位的刺激效应,通过联合使用红外热成像和激光多普勒血流成像技术,观察LED光针灸仪照射后裸鼠体表被照射区温度和微循环血流灌注变化,了解LED光针灸仪对照射区温度与血流灌注的影响。  相似文献   

5.
草莓用LED光源是针对植物的光合作用、光形态建成反应、光周期调节及光强对光谱的选择性,确定设施农业专用LED组合光源的主光谱辐射区,使其发射光谱与植物的选择性吸收光谱相匹配;根据LED的光色电性能指标,选取高亮度、不同功率的红、蓝、白色和远红光单色LED光源;通过对光色、光质、数量、排列进行优化组合来研制系列LED组件模块。出于工程上自动控制之需要,LED组合光源为行、列数各为9的方阵。  相似文献   

6.
基于菲涅尔透镜的室内LED射灯配光设计   总被引:3,自引:1,他引:2  
祝华  贺叶美  李栋 《光学仪器》2011,33(2):38-42
为了将LED发出的光均匀投射到3m远直径为1m的圆形区域内,设计了一种LED(发光二极管)射灯。采用菲涅尔透镜对射灯进行二次光学配光设计,并通过调整菲涅尔透镜的各个独立环带的倾角来优化投射光的分布。文中对菲涅尔透镜的投光效果、安全性和加工误差等方面进行了考察,结果表明设计是安全的、可靠的并具有良好的投光效果。  相似文献   

7.
单芯大功率LED匀光照明阵列的设计   总被引:2,自引:0,他引:2  
为构造大功率LED激发Cy3/Cy5荧光染料的均匀面照明系统,选择单芯大功率LED芯片PT54TE设计了红绿双通道匀光照明阵列。首先通过分析单芯大功率LED芯片PT54TE辐射强度的分布,建立大功率LED环形照明阵列的模型;然后为提高光线利用率,在LED外侧建立柱面镜反射结构,并通过斯派罗法则求解该结构的参数;最后由Tracepro仿真验证。研究表明,分别由4颗红/绿PT54TE构成的环形阵列在目标平面(30mm×30mm)内的光照均匀度大于95.4%,光通量大于700lm,比未配置柱面镜反射结构的环形阵列的光通量至少提高了52.5%。  相似文献   

8.
基于虚拟聚焦的板结构兰姆波换能器阵列检测方法研究   总被引:4,自引:4,他引:0  
针对板结构大范围无损检测问题,发展一种基于软件虚拟聚焦的兰姆波换能器阵列检测方法,即基于相控阵中等相位叠加原理,在无需相位控制硬件系统条件下,通过对换能器阵列接收数据进行软件处理,实现换能器阵列声束的指向聚焦.利用仿真数据,研究阵列直径、阵元数量、声束数量等对虚拟聚焦成像周向分辨率和旁瓣噪声的影响,得出检测结果无明显旁瓣噪声所需要满足的条件为阵元间距应小于检测兰姆波的半波长.基于数值仿真处理结果,进行电磁声换能器阵列兰姆波检测试验研究.结果表明,在选择合适的阵列直径、阵元数量、声束数量的条件下,通过对换能器阵列检测信号进行虚拟聚焦处理,可以实现板结构任意方向特征体(如边界)的识别和缺陷检测.  相似文献   

9.
针对LED照明通信集成芯片的应用,设计了一种包括蓝光LED和GaN PD的双向通信集成芯片。工作时蓝光和紫外光形成两路光通信。集成芯片的小尺寸可使LED照明通信减少一半的灯珠数量以利于缩小系统体积。对集成芯片采用串口通信协议和开关键控(OOK)调制解调装置进行单向、双向通信测试及分析。实验结果显示,集成芯片实现单向照明通信时,紫外通信误码率在10-6以下,在双向通信且蓝光LED电流密度不大于2.8mA/mm2时,紫外通信误码率在10-3以下。  相似文献   

10.
辜长明 《光学仪器》2010,32(3):49-54
为了实现将LED应用于基于光纤传输的照明系统中以替代传统光源,首先简要介绍了基于光纤传输照明系统的应用及组成,描述了LED应用于光纤传输照明系统设计的光学扩展量理论。根据光学扩展量理论分析了LED选型方法,总结了基于LED光纤传输照明系统的设计原则和要点。然后应用设计实例:基于红,绿和蓝三色LED合光的光纤照明模组,详述了设计过程,给出了测试数据。结果表明:LED可以应用于光纤传输照明系统中替代传统光源,市场前景广阔。  相似文献   

11.
远场均匀照明的LED排列设计   总被引:1,自引:0,他引:1  
郭靖  金尚忠 《光学仪器》2009,31(1):56-60
为了实现远场的照度均匀性,在已设计的LED平面排列组合的基础上,提出了LED白光照明单元的球面排列设计方法。相比平面的排列,把LED照明单元组合排列在半球形表面,在被照接收面上产生更宽角度的照度分布。并对几种不同排列的LED照明单元进行分析,建立了光学模型和设计方程式,模拟出远场的照度分布情况。结果表明在极限角度内LED球形排列具有均匀广泛的远场照度分布。  相似文献   

12.
Application of light‐emitting diodes (LEDs) in frequency‐domain fluorescence lifetime imaging microscopy (FLIM) has been limited by the trade‐off between modulation frequency and illumination intensity of LEDs, which affects the signal‐to‐noise ratio in fluorescence lifetime measurements. To increase modulation frequency without sacrificing output power of LEDs, we propose to use LEDs with multiple dice connected in series. The LED capacitance was reduced with series connection; therefore, the frequency response of multidie LED was significantly increased. LEDs in visible light, including blue, green, amber and red, were all applicable in FLIM. We also present a homogenizing optics design, so that multidie LEDs produced uniform illumination on the same focal spot. When the homogenizing optics was combined with multicolour emitters, it provides multiple colour selection in a compact and convenient design.  相似文献   

13.
用于机载液晶显示的四基色发光二极管背光源   总被引:1,自引:0,他引:1  
针对机载液晶显示的特殊要求,设计了一种四基色发光二极管(LED)背光源。采用了能单独控制亮度的红、绿、蓝、琥珀等4种颜色的LED,以克服现有滤光片方法带来的夜模式下显示色域大幅下降的问题。在昼模式下工作时,4种颜色的LED同时发光,混合成白光;在夜模式下工作时,关闭红色LED以减少红外辐射,而绿、蓝、琥珀等3种颜色LED工作。计算了夜模式下3种颜色的混合配比。将蓝色LED的混光比例作为固定值代入昼模式下计算得到红、绿、琥珀的配比。仿真设计了采用红、绿、蓝三合一LED和单独琥珀色LED的背光源,分析了它们的性能,并开发了实际样品。测试结果表明:昼模式下,背光模块的发光强度为23 515cd/m2(屏前亮度为1 175cd/m2),非均匀性为8.07%,色域为NTSC(National Television Standard Committee)的116.5%;夜模式下,背光模块的发光强度为15.36cd/m2(屏前亮度为0.77cd/m2),非均匀性为15.49%,色域为NTSC的83.5%,满足机载液晶显示的要求。  相似文献   

14.
There is a need for more practical, cost-effective and adaptive flow measurement instruments. Unfortunately, most of the current equipment still has to employ bulky and expensive laser systems for flow illumination. In this work we explore the practicability of using high-brightness high-power light-emitting diodes (LED) as a strobe-light illuminator within a double-frame micro particle image velocimetry (microPIV) system. A compact, cost-effective, and controllable LED driver was designed and applied to study the optical and spectral behavior of green and blue family direct-color single chip LEDs, which have excitation wavelengths corresponding to the most widely used fluorescent micro particles. To achieve strobe illumination, LEDs were subjected to high current double-pulsed operating regimes (up to 35 A at 20 μs pulse duration), which are much beyond their physical damage thresholds. We have witnessed that the blue family LEDs are more suitable for the fluorescence based microPIV experiments as they exhibit more stable spectral behavior at the double-pulsed high currents compared to the green colored LEDs. Specifically, we have observed that the spectral wavelength shift of blue family LEDs due to the high current is less severe and still enough to excite particles than that of green LEDs. Also, we have studied the relation between the pulse duration (as a means of parameter controlling signal-to-noise ratio) and the motion blur effect that arises due to the prolonged pulse durations. As a result, adequate pulse durations for most widely used microPIV experimental conditions were calculated. The feasibility and robustness of the developed double-pulsed LED illumination system was validated through a series of microPIV experiments with real flows inside two different topology microchannels, where the measured velocity was in good agreement with the corresponding analytical solutions. Overall, we can conclude that the high-brightness LED devices are promising candidates to replace their laser counterparts in the microPIV systems.  相似文献   

15.
李博  冯松  毛军红 《光学精密工程》2016,24(10):2347-2356
为了定量评价在线图像可视铁谱(OLVF)成像系统的像面照度均匀性,建立了一种像面照度模型。以像方参数及放大倍率表征物方视场,将物方视场区域离散化,采用朗伯余弦理论建立入瞳模式的像面照度模型,实现了像面照度的计算与均匀性评价。利用Matlab进行了物面照度仿真分析,确定了OLVF成像系统环形阵列光源的发光二极管(LED)数量,基于像面照度分析确定了最佳成像焦距和放大倍率。计算了油腔通油情况下成像系统中的光能量损耗以及磨粒沉积面的照度分布,建立了油液吸光系数与CCD像面轴上像点照度的关系。结果显示:LED发光强度已知时,仿真计算的像面不均匀度约为5.60%,实际测试的像面不均匀度为8%~9%,满足不均匀度≤10%的要求。开展了磨粒铁谱图像采集实验,结果表明:图像中磨粒清晰可辨,便于图像分割与视觉特征提取。提出的模型可定量描述OLVF成像系统的像面照度,可作为优化系统结构,提高系统成像性能的依据。  相似文献   

16.
Junction temperature (JT) is a key parameter of the performance and lifetime of light emitting diodes (LEDs). In this paper, a mobile instrument system has been developed for the non-contact measurement of JTs of LED under LabVIEW control. The electroluminescence (EL) peak shift of the LED is explored to measure the JT. Commercially available high power blue LEDs are measured. A linear relation between emission peak shift and JT is found. The accuracy of the JT is about 1 °C determined by the precision of the emission peak shift, ±0.03 nm, at 3σ standard deviation for blue LED. Using this system, on-line temperature rise curves of LED lamps are determined.  相似文献   

17.
A light calibration system consisting of a compact light-emitting diode (LED) source with feedback control of intensity is described. The source is positioned in the focal plane of the microscope objective and produces flat-field illumination of up to 31 μW. The source can be easily used to determine the performance of microscope optics and camera response. It can also be used as a standard light source for calibration of experimental systems. Selectable light intensities are produced by controlling the LED input power via a feedback circuit consisting of a photodiode that detects output light intensity. Spectral coverage extends between 550 and 670nm using green, yellow and red LEDs mounted side by side, which are selected individually. The LED chips are encapsulated in plastic diffusers which homogenize the light, and a flat field of illumination is obtained through a thin 1-mm-diameter aperture positioned directly over each chip. Provision is made for insertion of Ronchi rulings over the aperture to enable measurements of contrast modulation in a uniform field. The light may be pulse-modulated to assess camera response times and the device can be synchronized with video frames. Narrow bandpass interference filters can be placed between the objective lens and the LED source to produce monochromatic light without affecting the spacing of controlled light intensities since emission spectra do not shift appreciably over the range of LED powers chosen in this design. Results of tests using controlled light intensity and uniform illumination are presented.  相似文献   

18.
LED作为新兴光源,与传统的白炽灯光源相比,具有很大的优势。衡量其荧光材料发光性能的一个重要参数就是量子效率。为了准确地测量荧光材料的量子效率,提出了一种基于半积分球装置的量子效率测量系统。该系统采用了中心波长为465nm的蓝光LED芯片作为激发光源,与直径为150mm的半积分球和直径为150mm、中心孔直径为8mm的平面反射镜搭配使用,运用光纤和线阵CCD光谱仪采集光谱数据,并进一步计算出量子效率。为了验证系统的有效性,分别采用两种不同的荧光材料对测量系统进行测试,测量结果与厂商所给的数值基本一致。实验结果表明,该测量系统能有效地评估LED中荧光材料的发光性能。  相似文献   

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