# Light Tubes

A "Light Tube" is a way to let a LED (or NeoPixel) shine only through the Lid. It projects the light on the Lid of the project box.

<figure><img src="/files/SiWy6bV4XdPKVypCo70W" alt="" width="300"><figcaption></figcaption></figure>

```
Default origin = yappCoordPCB: PCB[0,0,0]

  Parameters:
   Required:
    p(0) = posx
    p(1) = posy
    p(2) = tubeLength
    p(3) = tubeWidth
    p(4) = tubeWall
    p(5) = gapAbovePcb
    p(6) = { yappCircle | yappRectangle }  : tubeType
   Optional:
    p(7) = lensThickness (how much to leave on the top of the lid for the 
           light to shine through) 0 for open hole : Default = 0/Open
    p(8) = Height to top of PCB : Default = standoffHeight+pcbThickness
    p(9) = filletRadius : Default = 0/Auto 
    n(a) = { <yappCoordPCB> | yappCoordBox | yappCoordBoxInside }
    n(b) = { yappNoFillet }

lightTubes = 
[
//--- 0,  1, 2,   3, 4, 5, 6,          7
    [15, 20, 1.5, 5, 1, 2, yappCircle, 0.5]
   ,[15, 30, 1.5, 5, 1, 2, yappRectangle]
];     
```

<table><thead><tr><th width="181"></th><th></th></tr></thead><tbody><tr><td><code>tubeLength</code></td><td>The length of the tube-window in the Y-ax direction</td></tr><tr><td><code>tubeWidth</code></td><td>The width of the tube-window in the X-ax direction</td></tr><tr><td><code>tubeWall</code></td><td>The wall thickness around the tube</td></tr><tr><td><code>abovePcb</code></td><td>The space between the PCB and the bottom of the light tube</td></tr><tr><td><code>lensThickness</code></td><td>Will make an opening in the Lid to let the light shine trough. If lensThickness is omitted there will be an open hole on top of the Lid, otherwise there will be a small layer of material on top of the Lid</td></tr><tr><td><code>tubeType</code></td><td>The shape of the window. Either a rectangle (yappRectangle) or a circle (yappCircle)</td></tr></tbody></table>

With this code:

```
lightTubes =
[
    [15, 20, 2, 6, 1, 5, yappCircle, 0.5]
   ,[15, 30, 2, 10, 1, 5, yappRectangle]
];
```

&#x20;You get these light tubes:

<figure><img src="/files/IDn5YgGb6a0p6ztnnFW9" alt=""><figcaption></figcaption></figure>


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