The default number of bumps is 100 (10 X 10). You need to change these bB^SD] }C
parameters to match your design. Note that LightTools allows many other "ct_EPr`
placement options, but you will use the Bezier placement option for this fRT Q5V
example. D;V FM P
5.On both the X Placement tab and Y Placement tab, change the Number of U 9?!|h;7
Bumps parameter to 300, as shown in the following figure. Click Apply after U[S#axak
each change. RyGce'
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6.Click OK to close the dialog box. (>
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Note that the number of bumps is 300 X 300, which results in about 90,000 >,8DwNuq
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a wec |~Rc-
manner defined by the Bezier parameterization option. Please see Chapter 5 of @Y#{[@Hp%
the LightTools Core Module User’s Guide for more information. With the l6 X\. oI
current parameter values, the Bezier option varies the bump spacing along the Dl3Df u8
length of the light guide. The spacing in the orthogonal direction is constant. | Wrf|%p
The X and Y refer to the local coordinate system of the surface. !V =s^8nj
LightTools Introductory Tutorial * 91 az (u=}
/CtR|~ w L
HAPTER 5 Introduction to Backlight Design D/CSR= b
C r+BPz%wM=O
Examining Surface Properties (aX5VB **
Using the methods described in previous chapters, you may want to check your .[-d( #l{l
model before you run a simulation. &b 2Vt
Click on various parts of the model in the 3D Design View. Or use the System aF:_ 1. LC
Navigator to select different surfaces and view their Properties. <B;l).[6
1.In the System Navigator, click to open BottomSurface of the LightGuide, then +G3&{#D
?
click Zones, and then click Texture. HNA/LJl[VU
2.Select SphericalElement, and then right-click and select Properties from the Ksq{=q-T
shortcut menu. The Shape tab shows you a graphical representation of the t`
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spherical bump shape that is the bottom of the light guide. G<C[ A
You might be curious as to why you cannot see the 3D texture property zones you #:v e3gWl
defined. They are invisible by default, because drawing thousands of texture D]9I-|
elements can make displaying and exploring the model somewhat slow. If you uvK1gJrA)
choose to make them visible, 3D textures are displayed in wireframe, even if the qbjLTE=
display mode is set to translucent. Wireframe rendering displays a bit faster and d#N< t`
shows more of the technical details. %Ot22a
92 * LightTools Introductory Tutorial :QnN7&j|(w
TR8<=
HAPTER 5 Introduction to Backlight Design 1/ Pou)D
C pJ6Z/ 3]
1.Rotate and zoom the model to that you can see something like the illustration t)n!];
below: s%nx8 "
. \:
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2.To reveal the Property Zones: slV+2b
a.Right-click in the Design View and select View Preferences to display this 'AX/?Srd
dialog box. Uhc2`r#q
b.On the Visibility tab, click the Property Zone check box to turn it on. 3,8>\yf`
c.Click OK. @N`) Z3P+
You will see the wire frame rendering of the spherical bumps on the n|vIo)
bottom surface, and a solid color above it. The solid color is the 3D texture Si#b"ls'
of the BEFs (brightness-enhancing films) built automatically by the utility.
