The default number of bumps is 100 (10 X 10). You need to change these g\=e86
parameters to match your design. Note that LightTools allows many other 3Tz~DdB
placement options, but you will use the Bezier placement option for this E *{_=pX
example. AMc`qh
5.On both the X Placement tab and Y Placement tab, change the Number of yf2 $HF
Bumps parameter to 300, as shown in the following figure. Click Apply after Gc{s?rB_
each change. HR$; QHl~F
6.Click OK to close the dialog box. |oV_7%mlu
Note that the number of bumps is 300 X 300, which results in about 90,000 #qg(DgH
7
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a n
?+dX^j
manner defined by the Bezier parameterization option. Please see Chapter 5 of =JfSg'7
the LightTools Core Module User’s Guide for more information. With the \#q|.d$ u
current parameter values, the Bezier option varies the bump spacing along the }WEF *4B!
length of the light guide. The spacing in the orthogonal direction is constant. tzdh3\6F
The X and Y refer to the local coordinate system of the surface. 41NVF_R6J
LightTools Introductory Tutorial * 91 @t<KS&
5nv1%48Ri
HAPTER 5 Introduction to Backlight Design
+z?SK c
C OzS/J;[PO[
Examining Surface Properties %
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Using the methods described in previous chapters, you may want to check your .fD%* -
model before you run a simulation. ?`U=Ps
Click on various parts of the model in the 3D Design View. Or use the System W^N|+$g>H
Navigator to select different surfaces and view their Properties. ^=7XA894
1.In the System Navigator, click to open BottomSurface of the LightGuide, then c`xgz#]v
click Zones, and then click Texture. d0D*S?#8,C
2.Select SphericalElement, and then right-click and select Properties from the eGQ -Ht,N
shortcut menu. The Shape tab shows you a graphical representation of the "*G p@
spherical bump shape that is the bottom of the light guide. N=~aj7B%
You might be curious as to why you cannot see the 3D texture property zones you %rq/&#jC
defined. They are invisible by default, because drawing thousands of texture q@O e}
elements can make displaying and exploring the model somewhat slow. If you (V9 ;
choose to make them visible, 3D textures are displayed in wireframe, even if the DBk]2W|i
display mode is set to translucent. Wireframe rendering displays a bit faster and J3,m{%EtNM
shows more of the technical details. s|d"2w6t
92 * LightTools Introductory Tutorial ! ,&{1p
/L*JHNu"_
HAPTER 5 Introduction to Backlight Design C}Ucyzfr,p
C XG}9) fT
1.Rotate and zoom the model to that you can see something like the illustration !FH m.E_>
below: %)p? &_
. l-<EG 9m@
2.To reveal the Property Zones: nV3I6
a.Right-click in the Design View and select View Preferences to display this >S'IrnH'!
dialog box. 9q_c`
b.On the Visibility tab, click the Property Zone check box to turn it on. p^*A&7d:P
c.Click OK. ,#Mt10e{
You will see the wire frame rendering of the spherical bumps on the OS sYmF
bottom surface, and a solid color above it. The solid color is the 3D texture sglH =0MP
of the BEFs (brightness-enhancing films) built automatically by the utility.
