The default number of bumps is 100 (10 X 10). You need to change these "p_[A
parameters to match your design. Note that LightTools allows many other b^|,9en
placement options, but you will use the Bezier placement option for this mhHm #
example. )I0g&e^Tzy
5.On both the X Placement tab and Y Placement tab, change the Number of T J"{nB
Bumps parameter to 300, as shown in the following figure. Click Apply after B1AF4}~5
each change. E '6 z7m.
6.Click OK to close the dialog box. :fMM-?s ]
Note that the number of bumps is 300 X 300, which results in about 90,000 gs2&0rnOy\
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a y5opdIaT
manner defined by the Bezier parameterization option. Please see Chapter 5 of jl ?y}
the LightTools Core Module User’s Guide for more information. With the 70 D Q/b
current parameter values, the Bezier option varies the bump spacing along the ~NJL S-
length of the light guide. The spacing in the orthogonal direction is constant. D\i8rqU/l
The X and Y refer to the local coordinate system of the surface. C ^ k3* N
LightTools Introductory Tutorial * 91 J jL0/&
h: (l+jr
HAPTER 5 Introduction to Backlight Design hrtN.4p[
C !&<Wc^ PG
Examining Surface Properties HoQ(1e$G-
Using the methods described in previous chapters, you may want to check your D yV[+P
model before you run a simulation. ,HjHt\!~<
Click on various parts of the model in the 3D Design View. Or use the System 8C4@V[sm`
Navigator to select different surfaces and view their Properties. >?Y3WPB<F
1.In the System Navigator, click to open BottomSurface of the LightGuide, then j l|X$w
click Zones, and then click Texture. Uu<sntyv
2.Select SphericalElement, and then right-click and select Properties from the "Mu $3 w
shortcut menu. The Shape tab shows you a graphical representation of the YJ;a{)e
spherical bump shape that is the bottom of the light guide. A 5\"e^>
You might be curious as to why you cannot see the 3D texture property zones you ;Q%19f3,6
defined. They are invisible by default, because drawing thousands of texture vzQmijr-
elements can make displaying and exploring the model somewhat slow. If you [_z2z6
choose to make them visible, 3D textures are displayed in wireframe, even if the Mdq'> <ajL
display mode is set to translucent. Wireframe rendering displays a bit faster and dXr
!_)i
shows more of the technical details. Tlv|To
92 * LightTools Introductory Tutorial t3kh]2t
L&F\"q9q71
HAPTER 5 Introduction to Backlight Design {Eb2<;1o{
C Sr -^faL
1.Rotate and zoom the model to that you can see something like the illustration SF}L3/C&h
below: \~m%4kzG8J
. t`/RcAwA
2.To reveal the Property Zones: w[7 HY@[
a.Right-click in the Design View and select View Preferences to display this !N2 n@bo
dialog box. I2!&=" 7@
b.On the Visibility tab, click the Property Zone check box to turn it on. qv >(
c.Click OK. Bk(XJAjY
You will see the wire frame rendering of the spherical bumps on the \y+F!;IxL
bottom surface, and a solid color above it. The solid color is the 3D texture CX (yrP6;
of the BEFs (brightness-enhancing films) built automatically by the utility.
