The default number of bumps is 100 (10 X 10). You need to change these =8"xQ>D62
parameters to match your design. Note that LightTools allows many other ~\<L74BB
placement options, but you will use the Bezier placement option for this ,,Ivey!kL
example. D^U?!S&4~
5.On both the X Placement tab and Y Placement tab, change the Number of u%=2g'+)_
Bumps parameter to 300, as shown in the following figure. Click Apply after Qv]rj]%
each change. Jc` tOp5
6.Click OK to close the dialog box. K*p3#iB
Note that the number of bumps is 300 X 300, which results in about 90,000 [dqh-7
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a $ERiBALN:
manner defined by the Bezier parameterization option. Please see Chapter 5 of H7meI9L
the LightTools Core Module User’s Guide for more information. With the b d C
current parameter values, the Bezier option varies the bump spacing along the 2i NZz
length of the light guide. The spacing in the orthogonal direction is constant. cJM.Q_I}Y
The X and Y refer to the local coordinate system of the surface. T{=&>pNK[
LightTools Introductory Tutorial * 91 O.8k [Ht
a(G}<
HAPTER 5 Introduction to Backlight Design 7?);wh 7`
C K<5 0>uG
Examining Surface Properties ,pVe@ d'
Using the methods described in previous chapters, you may want to check your ft4hzmuzM
model before you run a simulation. ~]'yUd1gSZ
Click on various parts of the model in the 3D Design View. Or use the System gyT0h?xDt
Navigator to select different surfaces and view their Properties. C5e;U
1.In the System Navigator, click to open BottomSurface of the LightGuide, then L@ejFXQg
click Zones, and then click Texture. +%K~HYN
2.Select SphericalElement, and then right-click and select Properties from the WSGho(\
shortcut menu. The Shape tab shows you a graphical representation of the VssWtL
spherical bump shape that is the bottom of the light guide. _g'x=VJF
You might be curious as to why you cannot see the 3D texture property zones you 2h)Qz+|7
defined. They are invisible by default, because drawing thousands of texture _c}# f\ +_
elements can make displaying and exploring the model somewhat slow. If you Q-1Xgw!
choose to make them visible, 3D textures are displayed in wireframe, even if the bU/YU0ZIT
display mode is set to translucent. Wireframe rendering displays a bit faster and )l`VE_(|
shows more of the technical details. "z_},TCy
92 * LightTools Introductory Tutorial Nx
E=^
v
"98j-L=F+
HAPTER 5 Introduction to Backlight Design ^uPg71r:
C OGG9f??
1.Rotate and zoom the model to that you can see something like the illustration kdhwnO
below: Q\btl/?
. Tk`|{Ph0
2.To reveal the Property Zones: 2(Aw
a.Right-click in the Design View and select View Preferences to display this P>03 DkbB
dialog box. %joU}G;"
b.On the Visibility tab, click the Property Zone check box to turn it on. e0<O6
c.Click OK. 4U u`1gtz
You will see the wire frame rendering of the spherical bumps on the u1\r:q
bottom surface, and a solid color above it. The solid color is the 3D texture yD@eT:lyi
of the BEFs (brightness-enhancing films) built automatically by the utility.