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基于LED光源隧道照明调光系统的研究与设计 总被引:1,自引:0,他引:1
针对隧道照明调光的要求,设计了一种基于PWM驱动大功率LED的调光系统.该系统采用恒流可控电路,主电路采用BUCK拓扑结构,控制电路采用自带PWM功能的单片机.通过对负载电流的采样,控制输出PWM脉冲的频率和占空比,以达到负载电流恒定的目的.该方法解决了LED在不同环境及时间内的亮度调节问题,且可在不改变其他电路参数的情况下增加或减少一定数量的LED,节约了成本,同时也给施工带来了极大的便利.试验表明,系统的各项性能指标均达到要求,抗干扰能力强. 相似文献
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本文介绍了一种采用单片机实现七彩LED光源控制的设计方案。单片机采用带PWM输出端口的AD型单片机,通过控制PWM(脉冲宽度调制)的占空比实现对R(红)、G(绿)、B(蓝)三色LED光源的光强度数字化调控,通过控制LED的R、G、B三色驱动和显示实现多彩的组合光调制,从而实现七彩效果的LED光源控制技术。 相似文献
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以PIC单片机为控制核心,提出了一种基于自适应PID控制器的160WLED16位数字调光系统的PWM恒流控制器的设计方案。用串联在160WLED电路中的电阻对LED电流进行检测得到电压信号,经过放大后,送PIC16F873A单片机的A/D转换器转换为量化值,通过与给定的亮度等级的PWM信号的第一次电流采样为基准电流信号进行比较,改变PWM输出的占空比控制LED的亮度等级。经测试,本系统能够实现160W白光LED在16位各级不同亮度时的恒流控制。 相似文献
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《电子制作.电脑维护与应用》2017,(7)
针对照明系统中能源浪费的问题,本文设计了一套智能照明控制系统。本系统以单片机AT89C52为控制核心,主要包括红外人体信号采集电路、光照强度采集电路以及控制电路。将热释电红外传感器和光敏电阻采集的数据,送单片机处理,再结合PWM调光技术,产生PWM信号,实现对LED光源的智能控制以及照明亮度的调节。通过实验验证,本系统可以达到智能和节能的目的。 相似文献
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提出了一种面向大视场高精度视觉测量的多红外目标靶点(红外LED)亮度自适应控制方法。以微控制器PIC16F873A和LED驱动芯片MAX6964作为核心器件,设计了可满足大空间范围内靶点亮度控制需求的多目标靶点控制驱动器。为了使LED在近距测量时的调节精度和远近距离测量时的发光亮度都能满足要求,根据MAX6964输出特点设计了PWM信号输出电路,并采用推挽电路驱动LED。实验证明,目标靶点在CCD相机上成像光斑稳定一致。 相似文献
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本文介绍了基于STC12C2052AD单片机的音乐喷泉系统,通过单片机自带的AD电路把声音模拟量转换成数字量,通过数字量去控制输出的PWM波形的占空比,从而通过控制输出电压来改变电机的转速与LED灯的亮度。 相似文献
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《微型机与应用》2016,(14):86-88
针对传统照明光源不能调色或调光深度不足的现象,选用功率为1 W的三基色发光二极管(RGB LED)为灯体,基于无线遥控和智能控制技术,通过PWM技术实现了LED灯白光的亮度调节、魔幻变色的自由切换及单色光输出的功能。系统由电源电路、一体化红外遥控接收头、CPU和三路LED驱动组成。采用低成本的STC15W201-SOP8单片机作为主控器件,用定时器作为三路的PWM发生器,驱动低开启电压的NMOS管以实现调光与调色。通过程序的巧妙设计实现了在0~360。过渡时无明显颜色跳变的现象。该可调光调色LED灯经长时间使用,调光调色效果理想且稳定可靠,可供该产品设计以参考。 相似文献
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赵静 《自动化技术与应用》2014,33(10):78-81
提出并设计了以LED作为光源进行远场光强测试的平台,包括光路与电路两大部分,详细描述了远场测量的实现方法、光电转换与信号处理过程、电路设计原理.运用MATLAB进行数据处理,拟合出远场光强分布曲线,分析了距离、辐射角度与光源强度的关系.经测试,在远场空间某一定点的光强值只与光源强度相关,在辐射角内可以直接体现光源稳定性. 相似文献
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《CVGIP: Graphical Models and Image Processing》1993,55(5):346-358
The diversity of lighting arrangements and fixtures in everyday life allows us great creative and functional control over the appearance of our environments. In computer graphics, the lack of realistic models of light sources does not permit the same level of control. To model a light source, one must (at least) be able to specify its geometry and its spatial intensity distribution. We describe a system that permits the interactive specification of point, linear, and area light sources having arbitrary and variable spatial intensity distributions across their domains. A continuous distribution of an extended light source is created by interpolating a set of sample distributions that are interactively placed on the light source. Rendering is accomplished by resampling the light source at a variable resolution. To speed up rendering, a pyramidal representation of the light source is created, allowing the dynamic selection of the resampling rate. We describe the theory, design, and implementation of our light-source modeling system. Pyramidal light-source models can be used in rendering environments such as conventional scanline or ray-tracing renderers, or renderers with programmable shaders. 相似文献
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一直以来浮标上用的锚灯都以白炽灯为光源,但是白炽灯功耗大、寿命短。为进一步提高航标灯的质量,减轻工人维护劳动强度和工作量,设计了一种低功耗且性价比高的可用于海洋测量浮标的太阳能LED锚灯。该锚灯通过中央控制器实现太阳能电池电源控制、蓄电池充电控制、感光电路控制以及LED锚灯控制等主要功能,并利用太阳能电池板进行充电,电路简洁、实用。LED锚灯灯管质量好、发光射程远、闪烁效果良好、性能稳定,可以更好地为浮标提供可靠的安全保证。 相似文献
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We have previously argued that an optical sensor combined total analysis system (TAS) is one of the indispensable functional components needed to realize a “ubiquitous human healthcare” system. To achieve this goal, we have proposed a fundamental structure for illuminating a minute cell or particle running along a microfluidic channel using a flat waveguide construction. It is desirable that the TAS light source should be arranged as close to the specimen flow as possible in order to acquire the necessary optical properties; hence, artificial defects formed on the surface of a flat light waveguide are considered to be a promising candidate for realizing the arbitrary-shaped light source for a highly functional optical TAS structure. Based on this idea, we fabricated a structure, constructing a flat and square light source consisting of rectangular solids, sub-micrometer in size, with a 1-μm thick and a 12-μm wide light waveguide core. We successfully trial-manufactured an optical TAS chip with a fluidic channel containing a 14 × 10-μm cross section, and an extremely flat light waveguide core. We repeatedly confirmed that the defect array could function as an approximately square light source when a 650-nm wavelength laser power was carefully introduced. Furthermore, we developed a hybrid numerical calculation method base on the finite-difference, time-domain method together with the beam propagation method. Utilizing this hybrid method, we evaluated the optical response when a particle runs across the light source while changing the aperture length of a shading mask to obtain signals with both higher intensity and shorter full width at half maximum. The numerical results were compared with experimental results obtained using an image acquisition system, and demonstrated good qualitative accord. 相似文献