The default number of bumps is 100 (10 X 10). You need to change these v 6Vcjm
parameters to match your design. Note that LightTools allows many other Q1l ' 7N
placement options, but you will use the Bezier placement option for this $D UZ!zaH!
example. + +# 5
5.On both the X Placement tab and Y Placement tab, change the Number of Cs i fKHI
Bumps parameter to 300, as shown in the following figure. Click Apply after A_#DJJMm
each change. F.v{-8GV
6.Click OK to close the dialog box. P A OJ\U
Note that the number of bumps is 300 X 300, which results in about 90,000 50C
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a UEVG0qF
manner defined by the Bezier parameterization option. Please see Chapter 5 of .K<Q&
the LightTools Core Module User’s Guide for more information. With the wg]LVW}
current parameter values, the Bezier option varies the bump spacing along the I15{)o(8$
length of the light guide. The spacing in the orthogonal direction is constant. B !=F2
The X and Y refer to the local coordinate system of the surface. -\n@%$M]G
LightTools Introductory Tutorial * 91 M { Q;:
.q 3/_*
HAPTER 5 Introduction to Backlight Design <kd1Nrr!p
C [=]4-q6UN
Examining Surface Properties lo!+f"7ym\
Using the methods described in previous chapters, you may want to check your ")HFYqP>9
model before you run a simulation. E1U",CMU
Click on various parts of the model in the 3D Design View. Or use the System aCLq k'
Navigator to select different surfaces and view their Properties. ; l-!)0 U
1.In the System Navigator, click to open BottomSurface of the LightGuide, then G<^{&E+=
click Zones, and then click Texture. 78H' a x9m
2.Select SphericalElement, and then right-click and select Properties from the _OC <[A
shortcut menu. The Shape tab shows you a graphical representation of the 9lDhIqx0~
spherical bump shape that is the bottom of the light guide. !o[7wKrXb
You might be curious as to why you cannot see the 3D texture property zones you H&} pkrH~
defined. They are invisible by default, because drawing thousands of texture A7hVHxNJ-
elements can make displaying and exploring the model somewhat slow. If you O|N{ v"o
choose to make them visible, 3D textures are displayed in wireframe, even if the Y]u+\y~
display mode is set to translucent. Wireframe rendering displays a bit faster and `P;s 8~
shows more of the technical details. E'.7xDN
92 * LightTools Introductory Tutorial )M//l1
qH 6>!=00
HAPTER 5 Introduction to Backlight Design _1L![-ac
C c#tjp(-
1.Rotate and zoom the model to that you can see something like the illustration ,tJ "
5O3-
below:
}sO&. ME
. :+|Z@KB
2.To reveal the Property Zones: 9
ea\ vZ
a.Right-click in the Design View and select View Preferences to display this 3% ;a)c;D
dialog box. R=
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b.On the Visibility tab, click the Property Zone check box to turn it on. ;H.^i|_/
c.Click OK. W PG(@zD
You will see the wire frame rendering of the spherical bumps on the PO 7Lf#9]
bottom surface, and a solid color above it. The solid color is the 3D texture @\P;W(m.i
of the BEFs (brightness-enhancing films) built automatically by the utility.
