导光柱设计指南

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光伏发电导光柱

光伏发电导光柱

光伏发电导光柱
光伏发电导光柱是太阳能光伏发电系统中的一部分,用于引导和集中太阳光到光伏组件上,最大限度地提高光能的转换效率。

它通常由光学材料制成,具有特殊的光学设计。

导光柱的主要功能是将散射的太阳光线聚焦到光伏组件上。

它可以通过总反射和折射的原理来实现这一目标。

导光柱的设计通常包括两个主要部分:
1.光收集器:光收集器位于导光柱的顶部,用于收集和聚焦
太阳光线。

它通常具有反射镜或聚光透镜的形式,并且能
够将光线从各个方向收集到一定的角度范围内。

2.光导路:光导路是导光柱的主体部分,通常是由高折射率
的材料制成(如光纤材料)。

它通过折射和反射光线的原
理将光线从光收集器传输到光伏组件的位置。

光导路内部
的表面通常具有特殊的几何形状,以最大限度地增加光的
传输效率和减小能量损失。

光伏发电导光柱的优点包括:
1.提高光能利用效率:通过导光柱的聚焦效果,能够将散射
的太阳光线集中到光伏组件上,提高光能的转换效率。

2.空间利用更灵活:导光柱可以使光伏组件更加灵活地布置
在不同的位置和角度,使其更好地适应不同的环境和安装
要求。

3.提高光伏系统的整体性能:通过引导和聚焦太阳光,导光
柱可以提高光伏系统的发电量,减少能量损失,并提高整个系统的效能。

需要注意的是,导光柱的设计和应用需要根据具体的光伏发电系统和环境条件进行定制。

因此,在使用导光柱之前,应根据实际情况进行光学计算和仿真。

导光柱设计指引之室内照明

导光柱设计指引之室内照明

Light PipeIn this chapter, you open, view, ray trace, and modify a simple plastic light pipe.Then, you do some basic illumination analysis, introduce a scattering surface, andsee the effect of this on the illumination distribution. This introduces you to manyof the basic techniques needed to use LightTools.ContentsWhat is a Light Pipe? (30)Opening, Viewing, and Selecting (31)Tracing Rays and Modifying the Light Pipe (35)Performing an Illumination Analysis (43)Optical Properties Example: Paint It White (52)Conclusions (55)C HAPTER3Learn by Doing: Analyze a Light Pipe What is a Light Pipe?to one or more illuminated areas.complex, and LightTools is a great tool for designing and analyzing such systems.You will start with a simple L-shaped plastic light pipe with a single flat surface to illuminate. This is similar to light pipes used to illuminate buttons or indicator lights in various devices.When you are finished, the light pipe will look something like this:In this chapter, you learn how to:•Open an existing LightTools model.•Use 3D viewing selection tools.•Trace a fan of rays and modify the light pipe to redirect the rays to illuminate the target surface.•Use a pre-defined light source (simulating an LED) and a receiver (collection surface) to run a simple Monte Carlo illumination simulation.•Apply an optical property (Lambertian scattering) to a surface and rerun the illumination simulation.Some of these features are briefly explained as they are introduced here, and additional explanation is included in subsequent chapters. The main purpose of this chapter is to get familiar with the interface and with typical tasks and procedures. This is a very simple system, but it allows you to explore some of LightTools basic features.C HAPTER 3Learn by Doing: Analyze a Light Pipe Opening, Viewing, and SelectingThe starting point for this light pipe model is supplied with the sample models in the LightTools installation directory . It is made of plastic (polycarbonate) andconsists of two blocks joined using Boolean operations, with a simple light source, and a rectangular dummy element (that is, an element that has no optical effect) with a receiver for illumination analysis. The source and receiver are on a hidden layer, so you won't see them at first .Opening the Model1.Select File > Open on the menu bar.If you didn’t close your model after you finished setting preferences, aLightTools message is displayed warning that your model hasn’t been saved. Click Yes to close it now and continue.2.On the Open dialog box, browse to the \Tutorial folder of the LightToolsinstallation directory, shown in the following figure.3.Click the file name TD_Lpipe_start.1.lts and click the Open button.Note: Be sure that you have set your preferences as described in Chapter2.C HAPTER 3Learn by Doing: Analyze a Light Pipe LightTools models are saved in files with the file extension .lts (for LightTools System).Viewing the ModelThe model opens, and the 3D Design view is displayed, showing four panes(nominally, top, right, front, and isometric views, but you can change each pane as desired). Note that one of the panes has a red border around it, indicating that this is the active pane for any operations that depend on view-based coordinates. (In LightTools , you can use several different coordinate systems in various types of tasks.)Now that a model is open, the navigation windows contain structured lists, which you will soon use to keep track of the parts of the system you are modeling and the various windows you will open. If you would like to explore the lists, click on plus signs (+) to expand hidden levels, and click on minus signs (-) to collapse a list.1.Make sure the lower right pane is active (has a red border), then click the 1Pane button on the toolbar.The right side view now fills the entire display area, and the 4 Panetoolbar button is available to return to the 4-pane view when desired . Although younow see only a single view of the model, the right mouse button and the toolbar let you quickly change that view as needed.C HAPTER 3Learn by Doing: Analyze a Light Pipe e these view operations to set up a view similar to the following picture. Todo this, you can:–Rotate the View . Place the cursor over the model, hold down the right mouse button, and slowly move the mouse around to spin the 3D Design view.–Zoom . Hold down the Control key and the right mouse button and move the mouse up or down. Move the mouse up to zoom in, or move the mouse down to zoom out.–Pan . Hold down the Shift key and the right mouse button and move the mouse to move the view around (pan up, down, left, right). Note: These view operations do not change any aspect of the model itself; you are simply “walking around” the model to view it from different virtual positions in space. Note that the coordinate axis rotates when you rotate the view. The objects in the model are fixed with respect to this global coordinate system. LightTools provides commands (such as Move ) to change the positionof selected object(s) within the model.C HAPTER3Learn by Doing: Analyze a Light PipeSelecting Objects and SurfacesAs explained in Chapter1, there are two aspects to selection: the object itself, and(in most cases) the surface of the object. Some operations affect the object as asurface(s).There are several tools that you can use to select objects, but because selection is needed so frequently, it is also the default operation, DefaultSelect. You will see this command in the 3D Design view command line whenever no other tool is selected.1.Click with the left mouse button on any visible surface of the light pipe.The wireframe outline of the model is highlighted to show that it is selected.The surface you click on changes color and a tag point (an “X”) is displayed on that surface. The name of the selected surface is also highlighted in the System Navigator.2.Click on the name of a different surface in the System Navigator.The corresponding surface is highlighted in the 3D Design view. If you click a surface that is not directly visible (for example, the back surface or bottom surface), you won't see the highlighting when the model is displayed intranslucent mode. If you use the right mouse button to rotate the view, you will see the highlighting.Tag pointC HAPTER 3Learn by Doing: Analyze a Light Pipe To get ready for ray tracing, the next step restores the original side view and changes the rendering mode from translucent to wireframe.3.To restore the YZ plane view and set the scale to fit all objects in the visibleplane, click these toolbar buttons:Y-Z Plane and then Fit .4.Select View > Render Mode > Wireframe to display only the edges of theobjects.Wireframe render mode makes it easier to see and work with rays, but in thismode, you can select objects only by clicking on an edge. With translucent and solid rendering, you can click anywhere on a rendered surface to select it.Tracing Rays and Modifying the Light PipeThe basic operation of LightToolsis ray tracing. Everything else is based to some extent on tracing one or many rays and doing some calculations with them . LightTools’ Monte Carlo simulation traces many rays (thousands, sometimes millions, from defined sources) to predict illumination distributions.“Point-and-Shoot” Ray TracingPoint-and-shoot rays are defined graphically, interactively, by clicking a starting point and then making additional clicks to define the direction and, in the case of fans and grids, the extent of the ray bundle . These rays are called non-sequentialC HAPTER3Learn by Doing: Analyze a Light Pipehit. You typically trace a relatively small number of point-and-shoot rays to view and understand the behavior of light in the system and to instantly see the optical effect when you make changes to the model. Going beyond the requirements of a simulation tool, this capability helps to make LightTools an excellent design tool.Once you begin running illumination simulations, you must explicitly re-run thesimulation when you make changes to the model.Using the Command PaletteAs described in The Command Palette on page15, clicking one of the six category buttons displays a set of sub-category buttons.Clicking a sub-category button then displays a set of command buttons.The category, sub-category, and commandbutton sequence is represented as follows:Some command buttons, such as the Ray Fan button shown here, require one ormore clicks in a specific sequence to execute. A diagram is provided on the button itself with the click sequence indicated in the diagram.The Command line shows the command name (NSFanFromPoint, in this case),and above the command line you will see prompts for the input. As you clickthrough the sequence using the mouse (or enter data directly in the Command line), the command sequence is built and, upon completion, is executed.Trace a Ray FanYou can trace single rays, a fan of rays, or a grid of rays. There are several types of fans and grids: parallel, diverging, and converging. In this example, you will have a light source located 0.5 mm to the left of the entering face of the light pipe. Use the cursor coordinates displayed at the lower right of the 3D Design view for thefollowing steps.Note: If you followed the setup instructions in Chapter2, there is a 0.1 mm snap grid active, which restricts the mouse motion to 0.1 mm increments, making it easier to hit specific points.C HAPTER 3Learn by Doing: Analyze a Light Pipe 1.Click the Ray Fan button (NSFanFromPoint ). The command panel buttonsequence is shown below.2.Click at the point (X = 0, Y = 0, Z = -0.5) to start the ray fan. Be sure to releasethe mouse button after clicking. Each point is discrete.3.Click at (0, 1, 1) to define the top of the fan, then click at (0, -1, 1) to define thebottom of the fan .Follow the prompts and watch the cursor coordinates to track the cursorlocation.PromptsCursor coordinatesC HAPTER 3Learn by Doing: Analyze a Light Pipe The fan is displayed. As you might expect, no light makes it to the desired output surface on top of the larger cube . You will have to modify the light pipe to get the light there. Note that the command button is no longer highlighted; to trace another ray fan, you would have to click the command button again .Make a CutTo reflect light to the top of the light pipe, you must introduce an angled surface. If the trim angle is correct, total internal reflection (TIR) will direct most of the light to the top surface without requiring any sort of coating. (TIR is the default surface property, but there are many others, as you will see.)1.Select the light pipe by clicking on any edge.2.Select the Trim button (TrimSolid ), shown below.To find out what the Trim button is used for, you can use What’s This? help.3.Select Help > What's This? on the main menu.The cursor changes to a question mark.Tip:The snap grid is not your only guide for precisely entering points . During anyoperation, you can right-click to display a shortcut menu with a Snapmenu item.You can snap points to objects, surfaces, coordinate axes, and even lines or rays.4.5.Click the X in the top right corner of the Help window to close it.6.Click the point (0, 0, 6.5) to define the section point, as prompted.The exact coordinate is not critical, because you will change it later to try to get more rays on the target surface. A “rubber band” line is displayed, along with text showing you the length and angle of the vector leading to the second point.7.Aim the normal vector at the lower right corner, making an angle of about -34º(the length is not critical), and then click to create the trim surface.If you make a mistake and trim away too much, select Edit > Undo and try again . It should look something like this:Name the ObjectIn the System Navigator, the Trim operation has created the new objectPlanePrimitive_n (where n is an integer). This is essentially an infinite “block” that has been Boolean-subtracted from the light pipe to form the trim plane surface, which is labeled HalfPlane (this is where the surface properties reside). You can keep the default name, but it is a good idea to give important objects a descriptive name, so they are easy to recognize later . In this case, you should rename the PlanePrimitive, because you will later modify the trim angle of this 3D object .Renaming is easy.1.In the System Navigator, right-click on PlanePrimitive_n and select Rename onthe shortcut menu.2.Type a new name, such as TIR_fold, and press Enter.3.Save the modified system:a.Select File > Save As .b.Navigate to the \LTUser (or other) directory.c.Key in a new name, such as Tut_Lpipe_trimmed.1.lts, and click Save.Note that the file name displays in the title bar (top edge) of the 3D Design view window.Changing PropertiesNow the light is getting to the collection surface, but it doesn't fill the surface and it isn’t very uniform. This is just a rough judgment based on a small number of rays, but it's often part of the iterative design process to use a few rays to make decisions about parameters, then do a Monte Carlo simulation to predict the illumination more precisely. It may not be possible to get a great distribution with a simple TIR surface, but it's easy to experiment with the angle and position of the trim surface.1.In the System Navigator, right-click on TIR_fold (the recently renamedPlanePrimitive_n ) and select Properties on the shortcut menu.The Properties dialog box gives you access to every detail of a model, and it changes, depending on the type of object selected . Right now, it displays the Coordinates tab, which applies to the entire selected object .(There is also ayou don’t need to use it at this time.)2.Move the Properties dialog box so that you can see the 3D Design view.3.Change the Absolute values of Z and Alpha to several different values, clickingApply each time.Can you get the ray fan to cover most of the top surface? The values shown (Z=6 and Alpha = 139º) are not necessarily optimum.4.Close the Properties dialog box. To do this, you can click the Cancel button orthe X in the top right corner.5.Click on the design view to make sure it is active.6.Save your modified file. This time, you can use File > Save, because you gave ita name when you saved it earlier.Tip: You can also click on the name of a window in the Window Manager to bring it forward and make it active.Tip: If the File menu is not displayed, the Properties dialog box may still be the active window. To re-display the menu bar, make the 3D Design view active.Performing an Illumination AnalysisPoint-and-shoot ray fans are great for simple analysis and design, because theyillumination performance, which requires several additions to the model: •One or more sources •One or more receivers •A few decisions, such as how many rays to trace, and whether or not to display them •Various charting features, which enable you to look at analysis resultsThe light pipe model already has a source and receiver, but they are on a hidden layer. Next, you will display them and do some quick illumination simulations . Later examples will explain the illumination results more extensively.LayersLightTools models can become very complex, with optical elements, mechanical parts, rays, sources, receivers, etc . The layer feature provides a way of managing this complexity, allowing you to separate objects on as many as 32 layers, any of which can be visible or hidden . A layer number is one of the properties assigned to a LightTools object. To see or set the layer number, right-click the object’s name in the System Navigation window, select the Properties shortcut menu and click on the Display tab.In this model, a light source and receiver for illumination analysis have already been defined and hidden on layer 2. Follow these steps to make them visible .1.Click on the design view.2.Select Edit > Preferences to display the Preferences dialog box.This dialog box controls many program parameters, with sections for General preferences, various defaults, and view-specific parameters for any views that are currently open (only the 3D Design view, in this case).Note: Making a layer visible or hidden affects only the display of objects, not their optical behavior. For example, a mirror on a hidden layer still reflects rays . To make 3D objects “invisible” to rays, you must use another option: the Ray Traceable check box on the Ray Trace tab of the Properties dialog box.3.In the navigation tree of the dialog box, click the plus sign (+) next to the ViewPreferences heading, and then click on the name of the 3D Design view below it.4.Click on the Layers tab to bring it to the front.5.Click the check box for layer 2 (Lum_Objects) to make it visible.6.Click OK.Clicking OK applies changes and closes the dialog box.The source and receiver symbols are now visible in the 3D Design view.Sources and Receivers Array This section briefly describes sources and receivers. Please see the LightToolsIllumination Module User’s Guide, Chapter2 and Chapter3 for detailedinformation about these types of objects.Sources.LightTools supports a variety of sources, from point sources to surface or volume emitters, in simple shapes to detailed lamp models made up of multiplesources and mechanical parts. You can also use simple sources with angular andspatial distributions (apodization files) applied to match measured or desireddistributions, as well as ray data sources created from measurements of realsources.Receivers. Receivers are special objects created to collect ray trace data forillumination calculations. LightTools supports spatial and angular receivers, andthey are usually attached to a surface of an object. (A far-field angular receiver is not attached to any object.)Receivers assign ray energy (weighted ray data) to bins (cells) in a collection mesh, and this allows the irradiance and other properties to be determined. There is a trade-off between radiometric accuracy (based on thenumber of rays per bin) and spatial accuracy (based on the number of bins across the receiver). LightTools allows you to re-bin the data without re-tracing the rays.In this sample model, a source and surface receiver are already defined. The source is a 1.0 watt point source with an apodization file attached to simulate the Gaussian intensity of an LED. The receiver is attached to the rectangular dummy element(named AirLens in this model, because that's its material) defined for this purpose.You can attach receivers to surfaces of real objects or to dummy elements,depending on your goals.Simulation Info and Ray PreviewA Monte Carlo simulation requires a large number of samples for accuratestatistical estimates of illumination. Samples in LightTools are traced rays, butunlike point-and-shoot rays, rays in an illumination simulation are traced in random directions from randomly selected points in or on the defined sources. Apodization and other factors affect the selection of random points so source behavior can beaccurately simulated.Before tracing large numbers of Monte Carlo rays, it’s a good idea to trace asmaller number with the Show Preview option turned on. When Show Preview is on, LightTools draws the rays in the design view, allowing you to see whether or notthings are working correctly. Drawing many rays may slow down the ray trace, so itmakes sense to keep the value for this option low or turn it off when you’re tracingthousands of rays (or more).1.Select Ray Trace > Simulation Input to display the Simulation Input dialogbox.2.Change the Total Rays to Trace to 200 and click Apply.3.Check the box next to the option Show Preview and enter 200 Rays.4.Click Apply, then OK.No rays are traced yet. You have just defined the parameters for the simulation.You can run the simulation from the Ray Trace menu or from the toolbar.5.Click the Begin All Simulations button or select Ray Trace > Begin All Simulations to trace and display the rays.Your 3D Design view should look something like the following figure. (The design view has been rotated in this example.)Understanding ChartsWhen you run a simulation, all of the output data is stored in memory; you see the results when you open an illumination chart . Because there are many ways to view and analyze illumination results, the best chart to display depends on your goals . In this example, you will look only at the illuminance (spatial) distribution on the predefined surface receiver . Other available analyses and charts (including the interactive LumViewer) will be discussed in later examples.Scatter charts are always a good starting point, because they are the closest thing to a view of the raw ray data. They don't tell you anything about the energy orstatistics, but they allow you to see how completely you have covered the receiver.1.With the 3D Design view active, select Analysis > Illuminance Display >Scatter Chart .With only 200 rays for preview, the scatter chart is not very dense, but it can help you understand the relationship between chart coordinates and system coordinates . In the figure below, the 3D Design view has been rotated so that the receiver surface has the same orientation as the chart . You can see that theNote: The menus always use the term illuminance , although, strictly speaking, this term applies only when photometric units are in use. In this example, the spatial distribution is in radiometric units of watts/mm 2.scatter chart is a kind of “ray diagram,” showing where the rays fall on the receiver surface.Tip:Chart coordinates are receiver coordinates. If you are not sure of the relationship between the chart coordinates and what you see in the design view, you can attach alocalcoordinate system to the surface holding the receiver. This was done in the figure above.To attach a local coordinate system, click the UCSOnSurface toolbarbutton, shown at left, and then click on the receiver surface . (UCS means user coordinate system. This is also the rotation point for right-mouseview operations.)A local coordinate system diagram is displayed on the surface. To return the UCS to the global origin, click the UCSToGLobalOrigin toolbarbutton, shown at left.Making the Big RunIf the simulation with a few rays doesn't show any major problems, you can try a bigger run.1.Click on the 3D Design view to make it active.2.Select Ray Trace > Simulation Input to display the Simulation Input dialogbox.3.Change the Total Rays to Trace to 10000.4.Clear the Show Preview check box and click OK.5.Click the Begin All Simulations buttonto trace the rays.This calculation will probably take a little longer (a few seconds or more,depending on your CPU’s speed). You may see the Progress dialog box, shownbelow. Tip: If a calculation ever takes too long, you can interrupt the simulation by clicking the Pause button . You can then look at other windows, and even opennew analysis windows to see if you have enough data. Then, click Continue or Stop in the Progress dialog box, as needed .Analysis Results and Re-binningAt this point, your scatter chart should be quite dense with rays. With more rays,the illuminance (actually, irradiance, in this case, with units of W/mm2 and no photometric weighting. Please see Chapter2 of the LightTools Illumination Module User’s Guide for information on radiometric vs. photometric calculations). To display a raster chart, make the design view the active window, and select Analysis > Illuminance Display > Raster Chart on the main menu.The raster chart shows a pseudo-color coded, graphically smoothed map of irradiance (spatial) distribution on the receiver, along with a histogram showing the energy levels. You can see a fairly “hot” region in the center, with dark edges. How much data is here? How accurate is it? As with most objects in LightTools, receivers and charts have properties, and you can look to them to answer these questions. 1.Right-click near the center of the raster chart (on the shaded area).The Properties dialog box for the Illumination Mesh_shade is displayed. Like other property dialog boxes, it has a small navigation tree. (You can also access mesh and other properties from the Illumination Manager section of the System Navigator, even if no charts are open.)2.Click on the plus sign (+) to expand the tree chart, then click on the sub-itemilluminanceMesh_n, (where n is a number).In this dialog box, the Properties tab shows that the Mesh Dimensions have been set to 9 bins by 15 bins. (Auto Mesh Boundaries, turned off in this case, is the default. It normally sets the number of bins to try to get a required accuracy level.) The Results tab contains read-only (calculated) values, including a(radiometric) Error Estimate at Peak, which should be about 10% for the 9x15 mesh . What if you have fewer bins?3.In the Properties tab, change the bins to X = 5 and Y = 9 and click Apply.The Error Estimate on the Results tab changes to around 6%. (Due to the statistical nature of Monte Carlo simulation, your numbers will not exactly match these.) This is called re-binning and is very useful for understanding the statistics of your illumination data . Note that in this case (with a TIR angled surface, with no coating), the total power is about 0.63 watts. The total power of the source is 1 watt.Tip: If you would like to see the content of two or more tabs at once, you canopen them in separate windows. To do this, right-click on the tab title, and selectOpen Tab in New Window on the shortcut menu, as shown above.Optical Properties Example: Paint It WhiteTo improve the uniformity of illumination in this case , you could try a number of techniques: “stair-step” extrusions, a curved surface, patterns of paint dots, or 3D textures (bumps or grooves), for example .One quick option to try is to paint it white . LightTools provides a number of pre-defined optical properties, including one called White Paint, in an easy-to-use library of properties. These library properties are created by combining several basic properties; for example, the White Paint property creates a Lambertianscatterer with 92% reflectance . You can, of course, set basic properties directly, and you can save and name your own combinations in .opr (for o ptical pr operty) files .1.In the 3D Design view, rotate the view so that you can click on the TIR_foldsurface.2.Right-click, and select Optical Properties on the shortcut menu.The Properties dialog box is displayed, with the Optical Properties tab in the foreground.3.Click the radio button for Load From Library.4.Select Surface Finishes from the first drop-down list, shown in the followingfigure.5.In the second drop-down list, select WhitePaint.1.opr.6.Click OK.Scattered rays tend to bounce and re-scatter, as illustrated in the followingdiagram. As a result, you may see some warning messages about maximum hits for the NS rays in your model. The reason is that if the rays hit a surface more than the default “max hits” of 1000 times, a warning is displayed in the Console window.Now you can re-run the illumination simulation with a single click.7.Activate the design view and click the Begin All Simulations button to re-run the simulation.8.Check the charts again. To bring a chart to the foreground, you can click on the chart window or click on the name of the chart in the Window Navigator. Although still less than optimum, the Scatter and Raster Charts both do show greater uniformity over a larger area of the receiver, as shown in the following figure.。

Light-Guideing导光柱设计指南

Light-Guideing导光柱设计指南

Light Guide Techniques导光技术Using LED Lamps使用LED光源Application Brief I-003导光柱是什么?导光柱就是将光以最小的损耗从一个光源传输到距离该光源一定距离的另一个点的装置。

光线是依靠全内反射在导光柱内部传输的。

导光柱通常是采用光学材料制成,如:丙烯酸树脂、聚碳酸酯、环氧树脂和玻璃。

导光柱可以用来将PCB上LED的光传输到产品面板上来显示相关的状态,也可以聚集和指引光线用做LCD显示屏的背光,同时也可以用来照亮在透过式窗口上的图案。

这篇文章论述了简单的导光柱的设计方法以适应这样或那样的应用。

基本原理Snell定律:当光线入射到两种不同的介质的交界面时,例如塑料和空气,光线会在通过这个交界面时产生折射,如图1所示。

光线射入这个交界面的角度叫做入射角φi,光线离开交界面的角度叫折射角φf Snell定律:ni*sinφi = nf*sinφf图1Snell定律规定:第一种介质的折射率ni乘以入射角φi的正弦值,等于第二种介质的折射率nf乘以折射角φf的正弦值。

镜面反射定律:镜面反射定律是这样定义的,光线的入射角与反射角相等,如图2所示,镜面反射光线是没有损耗的。

Fresnel Loss 菲涅耳损耗: 当光线通过交界面从一种介质进入另一种介质时,光线会因为在交界面上产生反射而产生损耗,如图2所示。

这种损耗称作菲涅耳损耗,可以用下面的公式进行计算:对于光线从塑料射入空气和从玻璃射入空气这两种情况下菲涅耳损耗都是4%当光线从折射率低的介质进入折射率高的介质时,折射角φf会小于入射角φi,相反,折射角φf会大于入射角φi,如图3所示光线穿过一个表面平行的塑料(玻璃)板。

图2图3 图4 完全内反射:当折射角等于90°时,入射光将会折射并沿着两种介质的交界面传播,如图4所示。

这时sin φf (90°) = 1.0,因此Snell定律就简化成ni*sin φi = nf. 这个公式可以用来计算产生完全内反射的临界入射角φc:空气的折射率为1.0,所以上式中的nf = 1.0,因此只要知道导光柱所采用的介质的折射率就能够迅速计算出这种介质内产生完全内反射的临界入射角.对于绝大多数的塑料和玻璃,它们的折射率约为1.50,因此,对于采用这两种材质制成的导光柱的完全内反射临界角约为42°导光柱内部与外界空气的交界面上产生的镜面反射可以用来帮助在导光柱内传输光线。

导光柱设计指南(二)2024

导光柱设计指南(二)2024

导光柱设计指南(二)引言概述:导光柱在光学设计中扮演着至关重要的角色,其设计需要考虑到光的损耗、均匀性以及耐用性等因素。

在本文档中,我们将为您介绍导光柱的设计指南,以帮助您更好地理解并应用于实际项目中。

正文:一、导光材料的选择1. 考虑光的透过率:选择具有较高透过率的材料可以提高导光柱的效果。

2. 注意折射系数:选择与周围环境折射系数相似的材料,以避免由于折射差异引起的光损耗。

3. 考虑机械强度:选用具有较高强度的材料,以保证导光柱的耐久性和长期稳定性。

4. 考虑导热性能:选择导热性能较好的材料,以避免导光柱在长时间使用时产生热损耗。

二、导光柱的形状设计1. 考虑光线传输路径:通过合理设计导光柱的外形,以使光线能够有效传输到出光端口。

2. 优化导光柱的截面形状:根据实际需求,选择合适的截面形状,如圆形、方形、矩形等,以实现最佳的光线均匀性和传输效率。

3. 控制导光柱的尺寸:根据实际应用需求,合理选择导光柱的尺寸,以达到最佳的光束输出效果。

4. 考虑光线的模式:根据需要选择适当的导光柱形状,以使光束能够保持高质量的模式。

三、表面处理和反射率控制1. 提高内部反射率:通过采用高反射率的涂层或反射膜处理导光柱的内表面,可以显著提高光的传输效率。

2. 控制外部反射率:采用减反膜或消光材料覆盖导光柱的外表面,以减少外部环境对光的干扰和损耗。

3. 考虑抗污染性能:选择具有良好抗污染性能的材料,以减少外界灰尘和污染对光束的影响。

四、降低光损耗和增强均匀性1. 减少反射和折射损耗:通过合理设计导光柱的表面和内部结构,减少光线在导光过程中的反射和折射损耗。

2. 控制光线出射角度:通过调整导光柱的形状和长度,控制光线的出射角度,以满足具体应用的需求。

3. 使用光学透镜:在导光柱的出光端口处使用光学透镜,以进一步控制光束的传播和发散角度。

五、导光柱的组装和安装1. 合理安装导光柱:根据具体应用需求,采取合适的安装方式,确保导光柱能够稳固地固定在系统中。

导光柱设计

导光柱设计

导光柱设计1、何为导光柱导光柱就是将光以最小的损耗从一个光源传输到距离该光源一定距离的另一个点的装置。

光线是依靠全内反射在导光柱内部传输的。

导光柱通常是采用光学材料制成,如:丙烯酸树脂、聚碳酸酯、环氧树脂和玻璃。

导光柱可以用来将PCB上LED的光传输到产品面板上来显示相关的状态,也可以聚集和指引光线用做LCD显示屏的背光,同时也可以用来照亮在透过式窗口上的图案。

(1) 选定合适的导光柱材料原则上尽量选用透光率高的材料,从下表1 可以看出:透明ABS、AS、PC的透光率相当,对遥控距离和角度的影响相差不大,实验A 的结果也验证了这一结论。

在注塑特性上,AS易粘模,脆性大,如选用此材料,要留意出模角度和顶出位置。

目前我公司使用的导光柱大部分为性能较好的PMMA 材料。

2、导光柱设计:●LED与导光柱入光面间距,设计建议值1mm对于贴片LED其发光区域是平坦的表面,导光柱的输入端应当做成光滑的与LED表面平行的平面,导光柱输入端贴近LED以提高光通量耦合效率,如图所示。

导光柱的输入端需要比LED的发光面略大以保证捕获92%的光线。

●导光路径需全部抛光,避免光损1)导光柱外表面的光滑是导光柱正常工作的重要保证,如图所示。

图中是一个从圆形输入端渐变到方形输出端的导光柱。

2)导光柱平行于光线传播方向的侧壁应当非常光滑,像镜子一样,这样光线才能够在其表面产生完全内反射。

3)导光柱的侧壁可以涂上白色反光涂料以反射角度小于临界角的光线,否则这些光线将会从导光柱侧壁逃逸到空气中造成损耗。

导光柱的入口应当光滑并与LED外形匹配以保证高效的捕获LED的光线,保证光线以最小的反射和散射进入导光柱内部。

4)对于矩形和特殊形状的导光柱,其拐角必须是圆角,半径不小于0.5mm,不能有尖角,以保证拐角处的照明。

5)导光柱的形状应当沿着其长度逐渐变化,例如从入口处与LED相匹配的圆形到出口处的正方形应当如图所示逐渐变化。

●出光面咬花#11000(细花纹),发光效果看起来比较均匀。

导光柱设计指南

导光柱设计指南

导光柱设计指南导光柱设计指南1、引言1.1 目的1.2 背景1.3 设计目标1.4 参考资料2、导光柱概述2.1 定义2.2 用途2.3 结构3、设计要求3.1 光学性能要求3.1.1 光传输效率3.1.2 光束均匀性3.1.3 色彩保真度3.2 结构要求3.2.1 耐久性3.2.2 抗震动性3.2.3 防尘防水性 3.3 安全要求3.3.1 防眩光性能3.3.2 防火性能4、导光柱设计步骤4.1 光学设计4.1.1 线光密度计算 4.1.2 材料选择4.1.3 反射率优化 4.2 结构设计4.2.1 材料选择4.2.2 结构优化4.2.3 连接件设计 4.3 安全设计4.3.1 防眩光设计4.3.2 防火设计5、测试与验证5.1 光学性能测试5.1.1 光传输效率测试 5.1.2 光束均匀性测试 5.1.3 色彩保真度测试 5.2 结构性能测试5.2.1 耐久性测试5.2.2 抗震动性测试5.2.3 防尘防水测试5.3 安全性能测试5.3.1 防眩光性能测试5.3.2 防火性能测试6、附件附件1、导光柱示意图附件2、光学性能测试数据附件3、结构性能测试数据附件4、安全性能测试数据法律名词及注释:1、光传输效率:导光柱中光线传输到输出端的比例。

2、光束均匀性:导光柱中光线强度在不同位置的均匀程度。

3、色彩保真度:导光柱中传输的光线颜色与原光源的颜色一致程度。

4、耐久性:导光柱在长期使用中不受磨损和损坏的能力。

5、抗震动性:导光柱在震动环境下不产生失效或破碎的能力。

6、防尘防水性:导光柱在接触尘埃和水分时保持正常工作的能力。

7、防眩光性能:导光柱在工作时不产生刺眼或眩光的能力。

8、防火性能:导光柱不易燃烧或不会使火势蔓延的能力。

本文档涉及附件:附件1:导光柱示意图附件2:光学性能测试数据附件3:结构性能测试数据附件4:安全性能测试数据。

电视机遥控导光柱的光学设计

电视机遥控导光柱的光学设计
2. 实验用仪器及材料:整机 2 台;不同材料颜色导光柱;不同形状导光柱; 3. 实验方法:对比试验 4. 实验内容及步骤
实验 A.测试不同颜色和材料的导光柱对遥控接收头灵敏度的影响 实验地点:科技大楼一楼展厅 实验对象:19L08 不同颜色和材料的导光柱 (用胶袋及标签区分),导光柱与接收头的距离 G=1.2mm (见图 14)。 接收头编号:5302-140038-00,19L08 导光柱编号:1007-19L080-01, PC(GE)原料黑色,能透过红外线,用在多媒体,导光柱编号:1007-29T0E0-01。
和角度的影响相差不大,实验 A 的结果也验证了这一结论。在注塑特性上,AS 易粘模,脆性大,如选用此材
料,要留意出模角度和顶出位置。目前我公司使用的导光柱大部分为性能较好的 PMMA 材料。
塑料名称 透光率(%) 参考价格 RMB(元/KG)
成型特性
备注
ABS(透明)
89
23
易成型
AS(SAN)
90
以一定比例混合,也可得到接近上述 A 之效果。(注:比例多少要通过实验取得)
(2) 合理放置接收头与导光柱的相对位置
红外线经导光柱折射传导后,最终的折射光线位置与导光柱的结构形状有较大关系,导光柱的结构形状
决定了接收头的摆放位置,如图 4 原因分析,图 5 为优化后的接收头摆放位置。
a.原位置
b.优化后位置
电视机遥控导光柱的光学设计
【摘 要】 文章主要介绍导光柱导光的原理,基于光学原理和实验探讨导光柱在电视机上优化设计和应用,
对彩电整机设计、生产中遇到相应的问题提出思路和方法。
【关键词】 光学原理 导光柱 接收头 设计 应用
一、 背景
电视机的遥控接收传感器(接收头)一般安装在机壳内,遥控器发出的红外线控制信号通过安装在机壳 的导光柱传导,作用于遥控接收传感器。导光柱既是遥控红外线传入遥控接收传感器的光路通道,也是电视 机外观的装饰零件,零件设计受到外观限制。针对近期我公司质量部反馈遥控接收角度不够、接收不灵敏的 情况,本文从导光柱的光学设计原理入手,结合实际遥控不良的机器,对现有的几款导光柱进行分析、改进及 对比实验,解决了遥控角度不够或遥控不灵敏的问题。本文还总结了导光柱设计的几种常见形式和设计要点, 给出了导光柱的优化设计方案。

导光柱结构设计规范

导光柱结构设计规范

導光柱設計要求1.1導光柱的定義導光柱(Light pipe)是用透明件或半透明的材料將PCB板上的LED光源發出的光導到產品外表面起到資訊、指示、閃光燈導光作用,由於是位於外觀面,因此還有裝飾的作用,今天的技術文章就結合我們藍牙耳機結構設計來分享導光柱的設計1.2導光柱的要求導光柱作為一個功能零件和外觀零件,需要同時滿足對於功能和外觀的要求。

1.3導光柱的材料一般採用PMMA(如奇美的PMMA C205)但也有採用PC(如GE的PC141R)1.4表面處理為避免看到內部元件,常採用表面咬花、染色或做成鋸齒面來避免透光(具體尺寸如下圖所示),同時為避免劃傷,外觀表面也應咬花。

表面主要採用粗店火花紋。

1.5裝配方式設計要點:1.5.1卡扣式這種裝配方式原理為當Light壓入時,殼體輕微變形,進入裝配位後殼體恢復即卡住Light,安裝簡易,生成效率高,可靠性較好,設計時優先推薦,各項尺寸推薦如下圖:相關注意事項:若卡合量太大,light材質較脆(PMMA),將可能導致碎裂。

①卡合量不能太大②變形件盡可能是殼體③由於此方式的Light較長,因此盡可能把燈設置在LED下面,保證透光1.5.2熱熔式此方式主要用於較大的導光柱,有較強的強度,可靠性好不易脫落;缺陷是:工藝複雜,生產效率低。

各尺寸推薦值:相關注意事項:①熱熔柱中間要做減縮孔:當導光柱主面厚度大於1.00mm時,可以設計成實心熱熔柱;否則為了防止外表面縮水,熱熔柱設計成中空②殼體需要做C角,可加強熱熔強度及熱熔效果③熱熔柱未熱熔時高出殼體H值一般取0.60mm~0.80mm左右,熱熔後殘留高度h要求為0.20~0.30mm,直徑2mm。

對於H值的計算可以按照熱熔前後體積一樣的原則進行計算,H 短了會影響熔接強度,H長了會導致h值大,容易與別的件發生空間干涉,所以一定要仔細計算H值。

1.5.3背壓式此方式較少採用,一般另有元器件頂住1.6常見的導光柱的形式及設計參考原則:①導光柱的材質為透明料,一般選用PC、PMMA;②導光柱一般用熱熔的方式裝到上面殼,熱熔柱直徑一般取1.00~1.20mm和熱熔孔的單邊間隙為0.05~0.10mm;③導光柱和麵殼孔的單邊配合間隙為0.10~0.15mm;④導光柱和導光源表面間隙為0.50mm左右;⑤導光柱的入光面採用光面,反射面採用光面,出光面可以採用紋面;理由:入光面採用光面,以利於更多的光線進入導光柱;反射面採用光面,以期望形成全反射效果,避免光線的損失;出光面採用紋面,以便出光形成漫射,以便在任何方位都可以看見指示燈亮;⑥導光柱的入光面有時為了聚光,可以做成凹面形狀1.7導光柱設計的目的1,讓LED燈透光更加均勻,不會出現燈光亮周圍暗的太陽光效果。

导光柱设计指南范文

导光柱设计指南范文

导光柱设计指南范文导光柱是一种具有导光功能的装饰品,它可以将光线从一端传输到另一端,使得整个导光柱都能亮起来,给人一种神奇的效果。

导光柱可以被广泛应用于建筑装饰、室内设计、舞台表演等领域。

然而,设计一根完美的导光柱并不是一件简单的事情,需要考虑多个因素。

下面将介绍一些设计导光柱的指南。

首先,导光柱的材料是至关重要的。

导光柱通常由透明材料制成,如有机玻璃、玻璃纤维等。

这些材料具有较高的透明度,可以让光线自由穿过,实现导光效果。

在选择材料时,还要考虑其耐用性和安全性,以保证导光柱的使用寿命和安全性能。

其次,导光柱的形状也是一个重要的设计因素。

常见的导光柱形状有圆柱形、方柱形、锥形等。

不同形状的导光柱在导光效果、光线扩散效果等方面可能有所不同。

设计师需要根据具体需求和效果来选择合适的形状。

导光柱的内部结构也需要仔细设计。

一般来说,导光柱内部会填充光导材料,如光导纤维。

光导纤维是一种能够将光线传输的材料,具有较高的透光率和导光效果。

设计师需要合理安排光导材料的布局,以实现最佳的导光效果。

此外,导光柱的灯光设计也是非常重要的。

一般来说,导光柱的灯光设计分为内部光源和外部光源两种。

内部光源是指在导光柱内部设置光源,使导光柱自身能够发光。

这种设计可以实现整根导光柱均匀发光的效果,但需要注意光源的布局和光线均匀度。

外部光源是指在导光柱旁设置光源,通过辐射光线照亮导光柱。

这种设计可以实现导光柱的外部效果,但对光源的位置和角度要求较高。

最后,导光柱的安装和维护也需要考虑。

导光柱一般是通过固定在地面或墙壁上来进行安装的。

设计师需要考虑导光柱的固定方式和固定位置,以保证其稳定性和安全性。

在维护方面,导光柱一般不需要特殊的维护,只需要定期清洁和检查,确保其正常使用即可。

综上所述,设计一根完美的导光柱需要考虑多个因素,包括材料选择、形状设计、内部结构、灯光设计、安装和维护等。

设计师需要有丰富的经验和创造力,才能设计出满足需求的导光柱。

导光柱设计(借鉴材料)

导光柱设计(借鉴材料)

导光柱设计1、何为导光柱导光柱就是将光以最小的损耗从一个光源传输到距离该光源一定距离的另一个点的装置。

光线是依靠全内反射在导光柱内部传输的。

导光柱通常是采用光学材料制成,如:丙烯酸树脂、聚碳酸酯、环氧树脂和玻璃。

导光柱可以用来将PCB上LED的光传输到产品面板上来显示相关的状态,也可以聚集和指引光线用做LCD显示屏的背光,同时也可以用来照亮在透过式窗口上的图案。

(1) 选定合适的导光柱材料原则上尽量选用透光率高的材料,从下表1 可以看出:透明ABS、AS、PC的透光率相当,对遥控距离和角度的影响相差不大,实验A 的结果也验证了这一结论。

在注塑特性上,AS易粘模,脆性大,如选用此材料,要留意出模角度和顶出位置。

目前我公司使用的导光柱大部分为性能较好的PMMA 材料。

表一各种材料的性能对比塑料名称透光率(%)折射率成型特性ABS(透明) 89 1.52 易成型,低温会开裂AS(SAN)90 1.56 易粘模,脆性PC 90 1.51 易成型PMMA 93 1.49 易成型,易脆,2、导光柱设计:●LED与导光柱入光面间距,设计建议值1mm对于贴片LED其发光区域是平坦的表面,导光柱的输入端应当做成光滑的与LED表面平行的平面,导光柱输入端贴近LED以提高光通量耦合效率,如图所示。

导光柱的输入端需要比LED的发光面略大以保证捕获92%的光线。

●导光路径需全部抛光,避免光损1)导光柱外表面的光滑是导光柱正常工作的重要保证,如图所示。

图中是一个从圆形输入端渐变到方形输出端的导光柱。

2)导光柱平行于光线传播方向的侧壁应当非常光滑,像镜子一样,这样光线才能够在其表面产生完全内反射。

3)导光柱的侧壁可以涂上白色反光涂料以反射角度小于临界角的光线,否则这些光线将会从导光柱侧壁逃逸到空气中造成损耗。

导光柱的入口应当光滑并与LED外形匹配以保证高效的捕获LED的光线,保证光线以最小的反射和散射进入导光柱内部。

4)对于矩形和特殊形状的导光柱,其拐角必须是圆角,半径不小于0.5mm,不能有尖角,以保证拐角处的照明。

Light Guideing导光柱设计指南

Light Guideing导光柱设计指南

Light Guide Techniques导光技术Using LED Lamps使用LED光源Application Brief I-003导光柱是什么导光柱就是将光以最小的损耗从一个光源传输到距离该光源一定距离的另一个点的装置。

光线是依靠全内反射在导光柱内部传输的。

导光柱通常是采用光学材料制成,如:丙烯酸树脂、聚碳酸酯、环氧树脂和玻璃。

导光柱可以用来将PCB上LED的光传输到产品面板上来显示相关的状态,也可以聚集和指引光线用做LCD显示屏的背光,同时也可以用来照亮在透过式窗口上的图案。

这篇文章论述了简单的导光柱的设计方法以适应这样或那样的应用。

基本原理Snell定律:当光线入射到两种不同的介质的交界面时,例如塑料和空气,光线会在通过这个交界面时产生折射,如图1所示。

光线射入这个交界面的角度叫做入射角φi,光线离开交界面的角度叫折射角φf Snell定律:ni*sinφi = nf*sinφf图1Snell定律规定:第一种介质的折射率ni乘以入射角φi的正弦值,等于第二种介质的折射率nf乘以折射角φf的正弦值。

镜面反射定律:镜面反射定律是这样定义的,光线的入射角与反射角相等,如图2所示,镜面反射光线是没有损耗的。

Fresnel Loss 菲涅耳损耗: 当光线通过交界面从一种介质进入另一种介质时,光线会因为在交界面上产生反射而产生损耗,如图2所示。

这种损耗称作菲涅耳损耗,可以用下面的公式进行计算:对于光线从塑料射入空气和从玻璃射入空气这两种情况下菲涅耳损耗都是4%当光线从折射率低的介质进入折射率高的介质时,折射角φf会小于入射角φi,相反,折射角φf会大于入射角φi,如图3所示光线穿过一个表面平行的塑料(玻璃)板。

图2图3图4完全内反射:当折射角等于90°时,入射光将会折射并沿着两种介质的交界面传播,如图4所示。

这时sin φf (90°) = ,因此Snell 定律就简化成ni*sin φi = nf. 这个公式可以用来计算产生完全内反射的临界入射角φc :空气的折射率为,所以上式中的nf = ,因此只要知道导光柱所采用的介质的折射率就能够迅速计算出这种介质内产生完全内反射的临界入射角.对于绝大多数的塑料和玻璃,它们的折射率约为,因此,对于采用这两种材质制成的导光柱的完全内反射临界角约为42°导光柱内部与外界空气的交界面上产生的镜面反射可以用来帮助在导光柱内传输光线。

导光柱设计指南

导光柱设计指南

导光柱设计指南1、何为导光柱导光柱就是将光以最小的损耗从一个光源传输到距离该光源一定距离的另一个点的装置。

光线是依靠全内反射在导光柱内部传输的。

导光柱通常是采用光学材料制成,如:丙烯酸树脂、聚碳酸酯、环氧树脂和玻璃。

导光柱可以用来将PCB 上LED 的光传输到产品面板上来显示相关的状态,也可以聚集和指引光线用做LCD 显示屏的背光,同时也可以用来照亮在透过式窗口上的图案。

(1) 选定合适的导光柱材料原则上尽量选用透光率高的材料,从下表1 可以看出:透明ABS 、AS 、PC 的透光率相当,对遥控距离和角度的影响相差不大,实验A 的结果也验证了这一结论。

在注塑特性上,AS 易粘模,脆性大,如选用此材料,要留意出模角度和顶出位置。

目前我公司使用的导光柱大部分为性能较好的PMMA 材料。

22.1、光线的反射和折射2.1.1、光的折射定律(菲涅耳定律)光线入射到不同介质的界面上会发生反射和折射。

必然会产生一束反射光线,光线也会在通过这个交界面时产生折射,如图所示。

其中入射光;折射光和法线位于同一个平面上,并且与界面法线的夹角满足如下关系。

光线射入这个交界面的角度叫做入射角θi ,光线离开交界面的角度叫折射角θf 。

斯涅尔定律:nisin θi= nfsinθf其中:ni 和nf 分别是两个介质的折射率;θi 和θf斯涅尔定律规定:nf 乘以折射角θf 的正弦值。

2.1.2、光的反射定律光线的入射角θi2.1.3、菲涅耳损耗当光线通过交界面从一种介质进入另一种介质时,光线会因为在交界面上产生反射而产生损耗,如图所示。

这种损耗称作菲涅耳损耗,可以用下面的公式进行计算:菲涅耳损耗=100×[(ni-nf )/(ni+nf )] ²当光从空气进入玻璃或透明塑料(PMMA;PC;AS)时:菲涅耳损耗=100×[(1.50-1.00)/(1.50+1.00)] ²=4%反之,当光从玻璃或透明塑料(PMMA、PC、AS)进入空气时,同样损失4%。

导光板和导光柱设计

导光板和导光柱设计

导光板和导光柱设计导光板导光板是利用光学级的压克力/PC板材,然后用具有极高反射率且不吸光的高科技材料,在光学级的压克力板材底面用UV网版印刷技术印上导光点。

利用光学级压克力板材吸取从灯发出来的光在光学级压克力板材表面的停留,当光线射到各个导光点时,反射光会往各个角度扩散,然后破坏反射条件由导光板正面射出。

通过各种疏密、大小不一的导光点,可使导光板均匀发光。

反射片的用途在于将底面露出的光反射回导光板中,用来提高光的使用效率。

导光板设计原理源于笔记本电脑的液晶显示屏,是将线光源转变为面光源的高科技产品。

光学级压克力(PMMA)/PC为基材,运用LCD显示屏及笔记本电脑的背光模组技术,透过导光点的高光线传导率,经电脑对导光点计算,使导光板光线折射成面光源均光状态制造成型。

产品采用光谱分析原理与数码UV印刷技术相结合并在恒温、恒湿、无尘的环境条件下制作而成。

具有超薄、超亮、导光均匀、节能、环保、无暗区、耐用、不易黄化、安装维修简单快捷等鲜明特点。

一般而言导光板因形状、制作方式和功能上都有不同的分类法,而且目前尚无统一的分法,经过整理后A、按照形状分为:平板和楔形板(斜板) 平板:导光板从入光处来看为长方形。

楔形板:从入光处来看为一边为厚一边为薄成楔形(三角形)状。

B、按照网点制作方式:印刷式和非印刷式印刷式:导光板完成外形加工后,以印刷方式将网点印在反射面,又分为IR(自然烘干和UV 光固化)两种。

非印刷式:将网点在导光板成形时直接成形在反射面。

又分为化学蚀刻(Etching)、精密机械刻画法(V-cut)、光微影法(Stamper)、内部扩散。

C、按照入光方式:侧入光(灯管和LED)和直下式。

侧入光式:将发光体(灯管或LED)放置于导光板之侧部。

直下式:将发光体(灯管或LED)放置于导光板之下方。

D、按照成形制作方式:射出成形和裁切成型。

射出成形:应用射出成形机将光学级PMMA 颗粒运用高温、高压射入模具内冷却成形.裁切成形:将光学级PMMA原板经过裁切工序完成成品。

导光结构设计

导光结构设计

【一】导光柱设计的目的是什么?1,让LED灯透光更加均匀,不会出现灯光亮周围暗的太阳光效果。

2,让非一条线直射出来的LED灯可通过转弯折射出来达到均匀透光效果。

3,让多种颜色的灯通过不同的导光珠形成多种颜色的灯光效果。

【二】导光柱光效如何达到均匀?得从以下几个方而去解决:1,光源的选择;以我们目前设汁的电子产品为列,目前比较多用的为LED灯珠,而选择LED的时候需要注意LED的这几个参数(功率,颜色,波长,发光角度,光通量,电压与电流),这些参数与LED 灯本体发光亮暗有关,而LED灯珠的种类又有好几种。

A,草帽形LED灯B,圆头LED灯D,椭圆LED灯珠E,方形LED灯珠F,子弹头LED灯珠注意灯头不是圆柱体G,平头LED灯珠H,食人鱼LED灯珠I,贴片式LED灯珠,正或侧发光2,导光材料的选择;A,导光材料选择,一般以PC与PHMA为主,PS与半透明的ABS为辅,透明导光效果最好是PHMA和PC,透光率可以达到92%以上效果。

B,导光材料+扩散粉的方式,如果LED灯设计为直射,只是为了透光均匀,则可以直接用半透的材料加扩散粉,或者透光件底部贴散光片,将光源扩散开,使透光达到均匀。

C,导光材料表面处理的方式,导光柱背面做咬花,磨砂或者雾而处理效果,或者纹理凹凸结构。

比如常见的光圈效果,在背部做咬花或者磨砂效果,表而也可以做0. 3*0. 3锯齿而防I匕透光,或者电火花规格用粗电火花纹(可用VDI27),然后注意导光柱与LED间的距离,不可太靠近,否则散光效果不好,LED灯要选用散射角度大点的。

3,光源的空间布置;在空间满足的情况下,尽量将LED灯布置为直射透光,导光柱增加扩散粉即可,或者离LED灯远一点,然后贴散光贴纸的方式。

如果空间不满足,又想透光面积大与透光均匀,可采用侧射光+导光板的方式,导光板上而印刷导光油墨。

具体根据结构空间与外观效果而泄义。

4,光的反射和折射处理;光学的东西理论性很强,导光原理一般都是利用全反射原理,要效果好的话,一般利用45度斜角效果或者圆弧形,或角度小于45度的情况。

lightguideing导光柱设计指南

lightguideing导光柱设计指南

Light Guide Techniques导光技术Using LED Lamps使用LED光源Application Brief I-003导光柱是什么导光柱就是将光以最小的损耗从一个光源传输到距离该光源一定距离的另一个点的装置。

光线是依靠全内反射在导光柱内部传输的。

导光柱通常是采用光学材料制成,如:丙烯酸树脂、聚碳酸酯、环氧树脂和玻璃。

导光柱可以用来将PCB上LED的光传输到产品面板上来显示相关的状态,也可以聚集和指引光线用做LCD显示屏的背光,同时也可以用来照亮在透过式窗口上的图案。

这篇文章论述了简单的导光柱的设计方法以适应这样或那样的应用。

基本原理Snell定律:当光线入射到两种不同的介质的交界面时,例如塑料和空气,光线会在通过这个交界面时产生折射,如图1所示。

光线射入这个交界面的角度叫做入射角φi,光线离开交界面的角度叫折射角φf Snell定律:ni*sinφi = nf*sinφf图1Snell定律规定:第一种介质的折射率ni乘以入射角φi的正弦值,等于第二种介质的折射率nf乘以折射角φf的正弦值。

镜面反射定律:镜面反射定律是这样定义的,光线的入射角与反射角相等,如图2所示,镜面反射光线是没有损耗的。

Fresnel Loss 菲涅耳损耗: 当光线通过交界面从一种介质进入另一种介质时,光线会因为在交界面上产生反射而产生损耗,如图2所示。

这种损耗称作菲涅耳损耗,可以用下面的公式进行计算:对于光线从塑料射入空气和从玻璃射入空气这两种情况下菲涅耳损耗都是4%当光线从折射率低的介质进入折射率高的介质时,折射角φf会小于入射角φi,相反,折射角φf会大于入射角φi,如图3所示光线穿过一个表面平行的塑料(玻璃)板。

图2图3图4完全内反射:当折射角等于90°时,入射光将会折射并沿着两种介质的交界面传播,如图4所示。

这时sin φf (90°) = ,因此Snell定律就简化成ni*sin φi = nf. 这个公式可以用来计算产生完全内反射的临界入射角φc:空气的折射率为,所以上式中的nf = ,因此只要知道导光柱所采用的介质的折射率就能够迅速计算出这种介质内产生完全内反射的临界入射角.对于绝大多数的塑料和玻璃,它们的折射率约为,因此,对于采用这两种材质制成的导光柱的完全内反射临界角约为42°导光柱内部与外界空气的交界面上产生的镜面反射可以用来帮助在导光柱内传输光线。

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导光柱设计指南
1、何为导光柱
导光柱就是将光以最小的损耗从一个光源传输到距离该光源一定距离的另一个点的装置。

光线是依靠全内反射在导光柱内部传输的。

导光柱通常是采用光学材料制成,如:丙烯酸树脂、聚碳酸酯、环氧树脂和玻璃。

导光柱可以用来将PCB 上LED 的光传输到产品面板上来显示相关的状态,也可以聚集和指引光线用做LCD 显示屏的背光,同时也可以用来照亮在透过式窗口上的图案。

(1) 选定合适的导光柱材料
原则上尽量选用透光率高的材料,从下表1 可以看出:透明ABS 、AS 、PC 的透光率相当,对遥控距离和角度的影响相差不大,实验A 的结果也验证了这一结论。

在注塑特性上,AS 易粘模,脆性大,如选用此材料,要留意出模角度和顶出位置。

目前我公司使用的导光柱大部分为性能较好的PMMA 材料。

22.1、光线的反射和折射
2.1.1、光的折射定律(菲涅耳定律)
光线入射到不同介质的界面上会发生反射和折射。

必然会产生一束反射光线,光线也会在通过这个交界面时产生折射,如图所示。

其中入射光;折射光和法线位于同一个平面上,并且与界面法线的夹角满足如下关系。

光线射入这个交界面的角度叫做入射角θi ,光线离开交界面的角度叫折射角θf 。

斯涅尔定律:nisin θi= nfsin
θf
其中:
ni 和nf 分别是两个介质的折射率;
θi 和θf
斯涅尔定律规定:nf 乘以折射角θf 的正弦值。

2.1.2、光的反射定律
光线的入射角θi
2.1.3、菲涅耳损耗
当光线通过交界面从一种介质进入另一种介质时,光线会因为在交界面上产生反射而产生损耗,如图所示。

这种损耗称作菲涅耳损耗,可以用下面的公式进行计算:
菲涅耳损耗=100×[(ni-nf )/(ni+nf )] ²
当光从空气进入玻璃或透明塑料(PMMA;PC;AS)时:
菲涅耳损耗=100×[(1.50-1.00)/(1.50+1.00)] ²=4%
反之,当光从玻璃或透明塑料(PMMA、PC、AS)进入空气时,同样损失4%。

当光线从折射率低的介质进入折射率高的介质时,折射角φf会小于入射角φi,相反,折射角φf会
大于入射角φi,如图所示光线穿过一个表面平行的塑料(玻璃)板。

2.2、全反射
当光线经过两个不同折射率的介质时,部份的光线会于介质的界面被折射,其余的则被反射。

但是,当入射角比临界角大时(光线远离法线),光线会停止进入另一介质,会全部向内面反射(见下图)。

发生全反射的条件:
(1)、光从折射率大的介质射入折射率小的介质;例如当光线从玻璃进入空气时会发生;
(2)、入射角大于临界角。

当折射角等于90°时,入射光将会折射并沿着两种介质的交界面传播,如图所示。

这时sinφf(90°) =1.0,因此斯涅尔定律就简化成ni*sinφi=nf。

这个公式可以用来计算产生完全
内反射的临界入射角φc:
Sinφc=nf/ni
空气的折射率为1.0,所以上式中的nf=1.0,因此只要知道导光柱所采用的介质的折射率就能够迅速
计算出这种介质内产生完全内反射的临界入射角。

对于绝大多数的塑料和玻璃,它们的折射率约为1.50,因此,对于采用这两种材质制成的导光柱的
完全内反射临界角约为42°。

Sinφc=1.0/1.50=0.667
导光柱内部与外界空气的交界面上产生的镜面反射可以用来帮助在导光柱内传输光线。

当光线在导光柱内与导光柱表面的入射角达到或大于42°时,将会在导光柱内部完全反射。

临界角小于45°的材料都非常适合用来制作导光柱,因为用这种材料可以制作成45°角反射面的导
光柱。

光线跟踪法:光线跟踪法可以用来分析和跟踪光线进入、穿过和射出一个导光柱的路径。

斯涅尔定律、菲涅耳损耗和镜面反射定律可以应用在所有导光柱表面的光线传播方向的分析上。

3、导光柱设计
在进行导光柱设计时首先需要考虑3个问题:
1)、有效的光通量耦合,以保证LED灯发射出的光线以最小的损耗进入导光柱内部;
2)、如何将光线通过导光柱传输到输出端;
3)、如何让光线以最小的损耗从输出端射出;
3.1、将LED光线耦合进导光柱内
在保证LED射出的光线有效的被传输和利用之前,必须首先保证它被有效的耦合进导光柱的进入端,
光线应当以最小的损耗被导光柱所捕获。

通常情况下,如果LED在导光柱的外部,并且与导光柱之间有空气间隙时光线的耦合和捕获效率是较
低的,相反,如果LED处于导光柱表面空气的交界面内部时,效率是最高的。

当LED在导光柱外部时,如图所示,在这种情况下只有在LED指示灯的光线辐射角与导光柱的光线接
收角相匹配的情况下耦合效率才会较高。

因此很难做到高效的光耦合,绝大部分LED产生的光都会损失掉。

在这样的结构设计下只有小于10%的光通量能被耦合进导光柱内。

在这种情况下如果采用一个凸透镜将LED输出的光线进行聚焦后耦合到导光柱内,如图所示,并且
聚焦后的光线刚好与导光柱输入端相匹配的话,光线捕获率可以达到80%。

但是这样的设计需要能够精确控制透镜与LED和导光柱之间的距离以保证正确的焦距,无疑会增加产品的成本。

导光柱最佳最有效的设计就是将LED固定到导光柱的内部,如图所示。

在这种结构中LED是植入导光
柱内部的,LED发出的所有光线全部会被导光柱所捕获,考虑到LED与导光柱之间存在空气间隙而产生的
菲涅耳损耗,光线捕获率可以达到92%。

如果将LED用光学环氧胶粘合到导光柱内部,如图所示,LED与导光柱之间将没有空气间隙因此也就
没有菲涅耳损耗,光线捕获率将会达到100%。

在绝大部分导光柱的应用中,这种方法既是不实际的也是
不必要的。

3.2、导光柱的物理特质:
导光柱外表面的光滑是导光柱正常工作的重要保证,如图所示。

图中是一个从圆形输入端渐变到方
形输出端的导光柱。

导光柱平行于光线传播方向的侧壁应当非常光滑,像镜子一样,这样光线才能够在其表面产生完全
内反射。

导光柱的侧壁可以涂上白色反光涂料以反射角度小于临界角的光线,否则这些光线将会从导光柱侧
壁逃逸到空气中造成损耗。

导光柱的入口应当光滑并与LED外形匹配以保证高效的捕获LED的光线,保证
光线以最小的反射和散射进入导光柱内部。

导光柱的出口应当是散射的,一个散射的出口端在其表面具遍布随机的临界角以保证光线可以从导
光柱内部逃逸出来,同时将光线以极宽的角度散射出去,这样不论从哪个角度看过去导光柱的出口端都
是亮的。

导光柱可以制作成任何形状,圆柱形、方形、锥形(尺寸从入口到出口逐渐增加)或任何特殊形状(箭头、星型、半月形等等)
对于矩形和特殊形状的导光柱,其拐角必须是圆角,半径不小于0.5mm,不能有尖角,以保证拐角处的照明。

导光柱的形状应当沿着其长度逐渐变化,例如从入口处与LED相匹配的圆形到出口处的正方形应当如图所示逐渐变化。

3.3、适应不同种类LED的导光柱入口:
导光柱的入口应当光滑并且平坦或者内凹并匹配LED的外形以保证高效的耦合和捕获光线。

对于贴片LED其发光区域是平坦的表面,导光柱的输入端应当做成光滑的与LED表面平行的平面,导光柱输入端贴近LED以提高光通量耦合效率,如图所示。

导光柱的输入端需要比LED的发光面略大以保证捕获92%的光线。

贴片LED的封装一般是立方体,光线是发散的,既从顶部射出也从侧面射出。

只有40%的光是从LED顶部射出的,另外60%的光是从LED侧面射出的。

因此,对于这种输入端是平面的导光柱来说只有40%的光可以被导光柱捕获,其余的光通量就损失掉了。

一个具有光滑内凹输入端的导光柱将有效提高光通量的捕获率,如图所示。

大约70%-80%的光量可以被导光柱捕获,光量的损失减小到20%至30%。

这种内凹的设计可以应用于任何导光柱与LED的组合以提高光通的耦合率和光线捕获能力。

3.4、导光柱的散射输出端:
散射的输出端能够使导光柱内的光线以随机的角度入射到导光柱与空气的交界面上,以保证光线在这个面上能够较容易的逃脱出去。

从这个表面逃逸的光线以随机的角度射出从而形成一个宽角度的照射范围,如图所示。

3.5、导光柱的拐角
导光柱可能需要弯曲成直角,为了减小光线的损耗,弯曲半径应当大于等于导光柱厚度的2倍(方形导光柱)或导光柱直径的2倍(圆柱形导光柱)。

光线沿着光滑的弯曲面反射而没有损耗产生,如图所示。

如果导光柱只能做成急速的90°转角,则可以在其转角处制作一个反射镜来改变光的方向,如图所示。

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