The default number of bumps is 100 (10 X 10). You need to change these *'%V}R[>
parameters to match your design. Note that LightTools allows many other kT% wt1T4
placement options, but you will use the Bezier placement option for this d*gAL<M7E
example. {& o^p!
5.On both the X Placement tab and Y Placement tab, change the Number of =[6^NR(
Bumps parameter to 300, as shown in the following figure. Click Apply after 3S^0%"fY
each change. ;c or\ R
6.Click OK to close the dialog box. ;]{ee?Q^ld
Note that the number of bumps is 300 X 300, which results in about 90,000 qt/K$'
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a s]arNaaA
manner defined by the Bezier parameterization option. Please see Chapter 5 of / ^.|m3
the LightTools Core Module User’s Guide for more information. With the 2w 2Bc+#o
current parameter values, the Bezier option varies the bump spacing along the j[>cv;h
;
length of the light guide. The spacing in the orthogonal direction is constant. "y1Iu
The X and Y refer to the local coordinate system of the surface. j4.wd
RK
LightTools Introductory Tutorial * 91 wP!X)p\
g^ AQBF
HAPTER 5 Introduction to Backlight Design ,YYEn^ :>
C GG} %
Examining Surface Properties >4:d)
Using the methods described in previous chapters, you may want to check your 1U 6B$(V^i
model before you run a simulation. uqMw-f/
Click on various parts of the model in the 3D Design View. Or use the System .E4* >@M5
Navigator to select different surfaces and view their Properties. P RKZg]?
1.In the System Navigator, click to open BottomSurface of the LightGuide, then nM,:f)z
click Zones, and then click Texture. -%nD'qy,.
2.Select SphericalElement, and then right-click and select Properties from the v}B%:1P4
shortcut menu. The Shape tab shows you a graphical representation of the ]%Q!%uTh
spherical bump shape that is the bottom of the light guide. vQAFg G
You might be curious as to why you cannot see the 3D texture property zones you ^h(wi`i
defined. They are invisible by default, because drawing thousands of texture !l:GrT8J
elements can make displaying and exploring the model somewhat slow. If you e+
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choose to make them visible, 3D textures are displayed in wireframe, even if the $|K
d<wv
display mode is set to translucent. Wireframe rendering displays a bit faster and l$42MRi/
shows more of the technical details. 9U8M|W|d
92 * LightTools Introductory Tutorial yI0bSu<j-
9t`;~)o
HAPTER 5 Introduction to Backlight Design .tBlGMcN
C jL VJ+mu
1.Rotate and zoom the model to that you can see something like the illustration .Y)[c. ,j
below: -YRIe<}E -
. +mQ5\14#
2.To reveal the Property Zones: Up9{aX
a.Right-click in the Design View and select View Preferences to display this u
v%Q5O4
dialog box. $( h T{C,K
b.On the Visibility tab, click the Property Zone check box to turn it on. 0-2|(9
Kc
c.Click OK. i\R0+ O{
You will see the wire frame rendering of the spherical bumps on the UKS 5{"=T[
bottom surface, and a solid color above it. The solid color is the 3D texture 5&]5*;Bv J
of the BEFs (brightness-enhancing films) built automatically by the utility.
