The default number of bumps is 100 (10 X 10). You need to change these J4l \
parameters to match your design. Note that LightTools allows many other N\nxo0sl
placement options, but you will use the Bezier placement option for this 9:v0gE+.
example. W3M1> (
5.On both the X Placement tab and Y Placement tab, change the Number of 62D UF
Bumps parameter to 300, as shown in the following figure. Click Apply after ZdsYIRU#
each change. ,"xr^@W
6.Click OK to close the dialog box. $uj3W<iw3E
Note that the number of bumps is 300 X 300, which results in about 90,000 !$Whftg
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a ar[I|
Q_
manner defined by the Bezier parameterization option. Please see Chapter 5 of ,CED%
the LightTools Core Module User’s Guide for more information. With the =Y ]'wb
current parameter values, the Bezier option varies the bump spacing along the ;RUod .x
length of the light guide. The spacing in the orthogonal direction is constant. WV?3DzeR
The X and Y refer to the local coordinate system of the surface. sn.0`Stt
LightTools Introductory Tutorial * 91 R[vA%G
C>=[fAr mO
HAPTER 5 Introduction to Backlight Design ?"Ec#,~
C $O[$<D%H
Examining Surface Properties ur @"wcl"V
Using the methods described in previous chapters, you may want to check your AbA_s I<;
model before you run a simulation. 1{K v
Click on various parts of the model in the 3D Design View. Or use the System t E(_Cg
Navigator to select different surfaces and view their Properties. 3vC"Q!J&
1.In the System Navigator, click to open BottomSurface of the LightGuide, then {?YBJnG}x
click Zones, and then click Texture. *P;
cSx?2
2.Select SphericalElement, and then right-click and select Properties from the G 5!J9@Yi
shortcut menu. The Shape tab shows you a graphical representation of the 'Z}3XVZEN
spherical bump shape that is the bottom of the light guide. J-U5_>S
You might be curious as to why you cannot see the 3D texture property zones you !l|fzS8g
defined. They are invisible by default, because drawing thousands of texture ZFFKv
elements can make displaying and exploring the model somewhat slow. If you *$ kpS ph
choose to make them visible, 3D textures are displayed in wireframe, even if the 3k_bhK zI
display mode is set to translucent. Wireframe rendering displays a bit faster and <nk7vo?Ks
shows more of the technical details. /3KPK4!m
92 * LightTools Introductory Tutorial H-C$ Jy)f"
*/)O8`}2
HAPTER 5 Introduction to Backlight Design m/bP`-/,
C HS@ EV iht
1.Rotate and zoom the model to that you can see something like the illustration rInZd`\
below: yR$ld.[uf
. z~($
"
2.To reveal the Property Zones: g 5@ P
a.Right-click in the Design View and select View Preferences to display this (kmrWx=
$
dialog box. -PiakX
b.On the Visibility tab, click the Property Zone check box to turn it on. 1a]QNl_x
c.Click OK. y}*J_7-
You will see the wire frame rendering of the spherical bumps on the MJug no
bottom surface, and a solid color above it. The solid color is the 3D texture WvN{f*
of the BEFs (brightness-enhancing films) built automatically by the utility.
