The default number of bumps is 100 (10 X 10). You need to change these b]g.>$[nX
parameters to match your design. Note that LightTools allows many other "?9fL#8f*!
placement options, but you will use the Bezier placement option for this 'b^:"\t'Rh
example. 1k/l7&n"
5.On both the X Placement tab and Y Placement tab, change the Number of .D>lv_kp
Bumps parameter to 300, as shown in the following figure. Click Apply after (wY% $kW4
each change. r P\ 7C+
6.Click OK to close the dialog box. %mYIXsuH
Note that the number of bumps is 300 X 300, which results in about 90,000 7R2)Klt
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a *r% mqAx(
manner defined by the Bezier parameterization option. Please see Chapter 5 of v S+ ~4Q41
the LightTools Core Module User’s Guide for more information. With the .$OInh
current parameter values, the Bezier option varies the bump spacing along the #U_u~7?H$
length of the light guide. The spacing in the orthogonal direction is constant. IkZ_N #m
The X and Y refer to the local coordinate system of the surface. ~fU Smc
LightTools Introductory Tutorial * 91 P`%ppkzV6
BA>0
+
HAPTER 5 Introduction to Backlight Design
Qom@-A
C S2s-TpjB<
Examining Surface Properties jN<]yhqf
Using the methods described in previous chapters, you may want to check your 2b"5/$|6
model before you run a simulation. !KlSw,&=.6
Click on various parts of the model in the 3D Design View. Or use the System =J'?>-B
Navigator to select different surfaces and view their Properties. Q:Ms D.
1.In the System Navigator, click to open BottomSurface of the LightGuide, then }-Ma ~/
click Zones, and then click Texture. aw4+1.xy
2.Select SphericalElement, and then right-click and select Properties from the .>nd@oU
shortcut menu. The Shape tab shows you a graphical representation of the -*Pt781
spherical bump shape that is the bottom of the light guide. 1*jL2P]D
You might be curious as to why you cannot see the 3D texture property zones you %7@H7 ^s}9
defined. They are invisible by default, because drawing thousands of texture gd ZVc9 _
elements can make displaying and exploring the model somewhat slow. If you AP7W) S
choose to make them visible, 3D textures are displayed in wireframe, even if the vp|=q;Q%r
display mode is set to translucent. Wireframe rendering displays a bit faster and s*X\%!l9
shows more of the technical details. w${=dW@K
92 * LightTools Introductory Tutorial Gehl/i-
["IJ h
HAPTER 5 Introduction to Backlight Design A X#!9-m3
C Zll ^tF#
1.Rotate and zoom the model to that you can see something like the illustration :y
%~9=
below: 1G;Ns] u
. 8{l=`y"nB
2.To reveal the Property Zones: qR<DQTO<
a.Right-click in the Design View and select View Preferences to display this o'4@]ae
dialog box. d&u/7rm
b.On the Visibility tab, click the Property Zone check box to turn it on. M0e|G.S&_
c.Click OK. w Ebs E<</
You will see the wire frame rendering of the spherical bumps on the Iz8 ^? >X
bottom surface, and a solid color above it. The solid color is the 3D texture M^f1D&A
of the BEFs (brightness-enhancing films) built automatically by the utility.
