The default number of bumps is 100 (10 X 10). You need to change these <Prz>qL$
parameters to match your design. Note that LightTools allows many other ], HF) 21
placement options, but you will use the Bezier placement option for this pIy+3 &\e;
example. Hki
5.On both the X Placement tab and Y Placement tab, change the Number of f H/J8<
Bumps parameter to 300, as shown in the following figure. Click Apply after ')Drv)L
each change. tz&oe
6.Click OK to close the dialog box. |lOH
P A
Note that the number of bumps is 300 X 300, which results in about 90,000 #sK:q&/G`
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a [80L|?, *
manner defined by the Bezier parameterization option. Please see Chapter 5 of ,dM}B-
the LightTools Core Module User’s Guide for more information. With the 7]w]i5
current parameter values, the Bezier option varies the bump spacing along the "[ 091 <
length of the light guide. The spacing in the orthogonal direction is constant. U!rhj&n
The X and Y refer to the local coordinate system of the surface. O *dN+o
LightTools Introductory Tutorial * 91 ersddb^J]
oyS43/."
HAPTER 5 Introduction to Backlight Design Bu\:+3 )
C t`6R)'
Examining Surface Properties kCO`J AH#
Using the methods described in previous chapters, you may want to check your \/Z?QBFvz
model before you run a simulation. n:-:LSa+3
Click on various parts of the model in the 3D Design View. Or use the System I'M,p <B
Navigator to select different surfaces and view their Properties. #R<ErX)F
1.In the System Navigator, click to open BottomSurface of the LightGuide, then 4]F:QS%
x
click Zones, and then click Texture. Wu\{)g{&
2.Select SphericalElement, and then right-click and select Properties from the #3l&N4 /
shortcut menu. The Shape tab shows you a graphical representation of the i1"4z tZ
spherical bump shape that is the bottom of the light guide. A3VXh^y+
You might be curious as to why you cannot see the 3D texture property zones you Hvto]~=GQ
defined. They are invisible by default, because drawing thousands of texture 1/O7K R`K
elements can make displaying and exploring the model somewhat slow. If you 2aef[TY
choose to make them visible, 3D textures are displayed in wireframe, even if the gi|j ! m
display mode is set to translucent. Wireframe rendering displays a bit faster and brk>oM;t
shows more of the technical details. MY]Z@
92 * LightTools Introductory Tutorial df=G}M(
x4&<Vr
HAPTER 5 Introduction to Backlight Design xU4,R cgo
C '$@bTW
1.Rotate and zoom the model to that you can see something like the illustration Q{ibH=^
below: WQ(*A
$
. Lc< v4Bp
2.To reveal the Property Zones: biJ"@dm
4
a.Right-click in the Design View and select View Preferences to display this e_Ue9c.}
dialog box. >}tm8|IHoo
b.On the Visibility tab, click the Property Zone check box to turn it on. SLyeonM-C
c.Click OK. 3]=j!_yJf
You will see the wire frame rendering of the spherical bumps on the 8Z{e/wnVF
bottom surface, and a solid color above it. The solid color is the 3D texture i /j
DwA
of the BEFs (brightness-enhancing films) built automatically by the utility.
