The default number of bumps is 100 (10 X 10). You need to change these (@u"
parameters to match your design. Note that LightTools allows many other "CWqPcr
placement options, but you will use the Bezier placement option for this u !VY6y 7p
example. Q92hI"
5.On both the X Placement tab and Y Placement tab, change the Number of NIOWjhi[Jn
Bumps parameter to 300, as shown in the following figure. Click Apply after [;i3o?\_I
each change. vn=0=(
6.Click OK to close the dialog box. _;5N @2?
Note that the number of bumps is 300 X 300, which results in about 90,000 r)t-_p37
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a {nmBI k2v
manner defined by the Bezier parameterization option. Please see Chapter 5 of !xZ`()D#
the LightTools Core Module User’s Guide for more information. With the N]@e7P'9F
current parameter values, the Bezier option varies the bump spacing along the ig,v6lqhM
length of the light guide. The spacing in the orthogonal direction is constant. E@ $HO_;&
The X and Y refer to the local coordinate system of the surface. 'x\{sv
LightTools Introductory Tutorial * 91 J"RmV@|
<)9 E .h
HAPTER 5 Introduction to Backlight Design R a?0jcSQ$
C erZ%C <
Examining Surface Properties ~ f>km|Q{u
Using the methods described in previous chapters, you may want to check your Jx1JtnyP@
model before you run a simulation. ns[Q %_
Click on various parts of the model in the 3D Design View. Or use the System mq~L1< f
Navigator to select different surfaces and view their Properties. ,;wc$-Z!8
1.In the System Navigator, click to open BottomSurface of the LightGuide, then ~w9ZSSb4
click Zones, and then click Texture. {VrjDj+Xy
2.Select SphericalElement, and then right-click and select Properties from the .9;wJ9Bw[
shortcut menu. The Shape tab shows you a graphical representation of the at `\7YfQp
spherical bump shape that is the bottom of the light guide. ? v2JuhRe
You might be curious as to why you cannot see the 3D texture property zones you %]i("21
defined. They are invisible by default, because drawing thousands of texture qy|si4IU8,
elements can make displaying and exploring the model somewhat slow. If you `JL&x|q o
choose to make them visible, 3D textures are displayed in wireframe, even if the \a\ApD
display mode is set to translucent. Wireframe rendering displays a bit faster and .FXn=4l'vV
shows more of the technical details. !>5!Fb=Sy
92 * LightTools Introductory Tutorial .!hB tR
gkyv [
HAPTER 5 Introduction to Backlight Design KUqD<Jj?
C BWN[>H %S
1.Rotate and zoom the model to that you can see something like the illustration #<|q4a{8
below: [3QK BV1\
. Xz, sL
2.To reveal the Property Zones: T&`H )o
a.Right-click in the Design View and select View Preferences to display this U$( AZ|0
dialog box. RI% ZT
b.On the Visibility tab, click the Property Zone check box to turn it on. |YAnd=$
c.Click OK. S QB[ d3f
You will see the wire frame rendering of the spherical bumps on the \!4sd2Yi
bottom surface, and a solid color above it. The solid color is the 3D texture GM<r{6Qy
of the BEFs (brightness-enhancing films) built automatically by the utility.
