The default number of bumps is 100 (10 X 10). You need to change these GyxLzrp
parameters to match your design. Note that LightTools allows many other yH s9J1S f
placement options, but you will use the Bezier placement option for this +"WNG
example. "W4|}plnu
5.On both the X Placement tab and Y Placement tab, change the Number of [9~ EH8
Bumps parameter to 300, as shown in the following figure. Click Apply after 7TypzgXNe
each change. 7J$rA .tu
6.Click OK to close the dialog box. y/_=
Note that the number of bumps is 300 X 300, which results in about 90,000 9h-S,q!
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a ;H71A[M
T
manner defined by the Bezier parameterization option. Please see Chapter 5 of 4XJ']M(5;
the LightTools Core Module User’s Guide for more information. With the Pd d(1K*
current parameter values, the Bezier option varies the bump spacing along the `O.pT{Lf
length of the light guide. The spacing in the orthogonal direction is constant. ;"9Ks .
The X and Y refer to the local coordinate system of the surface. Rw[!Jq
LightTools Introductory Tutorial * 91 XS^du{ai
U Lq`!1{
HAPTER 5 Introduction to Backlight Design 3|G~_'`RLt
C J &=5h.G$
Examining Surface Properties SL N OOE N
Using the methods described in previous chapters, you may want to check your ;BWWafZ
model before you run a simulation. 9aIv|cS?
Click on various parts of the model in the 3D Design View. Or use the System ^Df qc- ]
Navigator to select different surfaces and view their Properties. Iw#[K
1.In the System Navigator, click to open BottomSurface of the LightGuide, then :(3'"^_NA
click Zones, and then click Texture. lq`7$7-4
2.Select SphericalElement, and then right-click and select Properties from the ~W V1t][
shortcut menu. The Shape tab shows you a graphical representation of the )M[FPJP}
spherical bump shape that is the bottom of the light guide. I7|a,Q^f
You might be curious as to why you cannot see the 3D texture property zones you :c )R6=v
defined. They are invisible by default, because drawing thousands of texture wxvVtV{u>|
elements can make displaying and exploring the model somewhat slow. If you Jzy:^PObT
choose to make them visible, 3D textures are displayed in wireframe, even if the l_+q a6C*
display mode is set to translucent. Wireframe rendering displays a bit faster and r,vSDHb` j
shows more of the technical details. h.- o$+Sa
92 * LightTools Introductory Tutorial }I`o%GL
AtAu$"ue
HAPTER 5 Introduction to Backlight Design e(DuJ-
C /9P7;1?
1.Rotate and zoom the model to that you can see something like the illustration 7Ot&] M
below: ?h# F& y
. Z~|%asjFE
2.To reveal the Property Zones: fG.6S"|M
a.Right-click in the Design View and select View Preferences to display this D`B*+
dialog box. UA0(
cK
b.On the Visibility tab, click the Property Zone check box to turn it on. fbah~[5}
c.Click OK. QT1oU P#*
You will see the wire frame rendering of the spherical bumps on the q_> =| b
bottom surface, and a solid color above it. The solid color is the 3D texture 4m~p(r
of the BEFs (brightness-enhancing films) built automatically by the utility.
