The default number of bumps is 100 (10 X 10). You need to change these _L8&.=4]i
parameters to match your design. Note that LightTools allows many other Z*Ffdh>*:&
placement options, but you will use the Bezier placement option for this w (HV C
example. N)(m^M(~0
5.On both the X Placement tab and Y Placement tab, change the Number of f?Ex$gn I
Bumps parameter to 300, as shown in the following figure. Click Apply after g;Fd m5Q
each change. `pbCPa{Y
6.Click OK to close the dialog box. " 0!#De
Note that the number of bumps is 300 X 300, which results in about 90,000 MO ~T_6
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a ky !Z JR
manner defined by the Bezier parameterization option. Please see Chapter 5 of ]Z[3 \~?
the LightTools Core Module User’s Guide for more information. With the dtuCA"D
current parameter values, the Bezier option varies the bump spacing along the L@MCB-@V
length of the light guide. The spacing in the orthogonal direction is constant. azmeJpC
The X and Y refer to the local coordinate system of the surface. 0^{Tq0Ri[
LightTools Introductory Tutorial * 91 7'+`vt#E
J|xXo
HAPTER 5 Introduction to Backlight Design 9@t&jznt<
C oxFd@WV5
Examining Surface Properties K;/f?3q
Using the methods described in previous chapters, you may want to check your FBNi (D
model before you run a simulation. O #tmB?n*
Click on various parts of the model in the 3D Design View. Or use the System ->|eMV'd
Navigator to select different surfaces and view their Properties. 8k{ XUn
1.In the System Navigator, click to open BottomSurface of the LightGuide, then Q-,
4
click Zones, and then click Texture. W[QgddR
2.Select SphericalElement, and then right-click and select Properties from the fCa
lR7!
shortcut menu. The Shape tab shows you a graphical representation of the [GyPwb-
spherical bump shape that is the bottom of the light guide. >o"s1*
{
You might be curious as to why you cannot see the 3D texture property zones you UHY)+6qt]
defined. They are invisible by default, because drawing thousands of texture >a@1y8B
elements can make displaying and exploring the model somewhat slow. If you G}
[$M"}
choose to make them visible, 3D textures are displayed in wireframe, even if the GF9iK|i/
display mode is set to translucent. Wireframe rendering displays a bit faster and }f>
81[^
shows more of the technical details. H"+|n2E^
92 * LightTools Introductory Tutorial P,S!Z&!
0lt1/PEKx2
HAPTER 5 Introduction to Backlight Design d;%~\+)x4
C 5UL5C:3R9
1.Rotate and zoom the model to that you can see something like the illustration Xj?LU7
below: fk^DkV^<
. 2wU,k(F_
2.To reveal the Property Zones: @bkSA
a.Right-click in the Design View and select View Preferences to display this a&)$s;
dialog box. 6wiuNGZb
b.On the Visibility tab, click the Property Zone check box to turn it on. x =JZ"|TE
c.Click OK. e,vgD kI;
You will see the wire frame rendering of the spherical bumps on the ke*&*mx"L
bottom surface, and a solid color above it. The solid color is the 3D texture 9Lt3^MKa"
of the BEFs (brightness-enhancing films) built automatically by the utility.
