The default number of bumps is 100 (10 X 10). You need to change these XKS8K4"
parameters to match your design. Note that LightTools allows many other /<{: I \<
placement options, but you will use the Bezier placement option for this T^:fn-S}=
example. `\CVV*hP
5.On both the X Placement tab and Y Placement tab, change the Number of YlF%UPp
Bumps parameter to 300, as shown in the following figure. Click Apply after n B5zNyY4
each change. y >+mc7n
6.Click OK to close the dialog box. E\U`2{ ^.
Note that the number of bumps is 300 X 300, which results in about 90,000 k~.&j"K
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a -LW [7s$
manner defined by the Bezier parameterization option. Please see Chapter 5 of CU)|-*uiK
the LightTools Core Module User’s Guide for more information. With the bt$)Xu<R
current parameter values, the Bezier option varies the bump spacing along the MTOy8 Im
length of the light guide. The spacing in the orthogonal direction is constant. `5~3 G2T
The X and Y refer to the local coordinate system of the surface. bZ1 78>J]
LightTools Introductory Tutorial * 91 .(CP. d
~j9O$s~)
HAPTER 5 Introduction to Backlight Design ,Lr<)p
C N<(.%<!
Examining Surface Properties VQ#3#Hj
Using the methods described in previous chapters, you may want to check your 2lVHZ\G
model before you run a simulation. Z\}K{#
Click on various parts of the model in the 3D Design View. Or use the System E&$yuW^z
Navigator to select different surfaces and view their Properties. s?R2B)a
1.In the System Navigator, click to open BottomSurface of the LightGuide, then P
[Uy
click Zones, and then click Texture. :Bu2,EL*O
2.Select SphericalElement, and then right-click and select Properties from the qqrq 11W
shortcut menu. The Shape tab shows you a graphical representation of the sBrI}[oyx
spherical bump shape that is the bottom of the light guide. OO[F E3F
You might be curious as to why you cannot see the 3D texture property zones you \]$IDt(s
defined. They are invisible by default, because drawing thousands of texture !uQPc
elements can make displaying and exploring the model somewhat slow. If you ~3uP6\F
choose to make them visible, 3D textures are displayed in wireframe, even if the P#=`2a#G
display mode is set to translucent. Wireframe rendering displays a bit faster and [JF150zr
shows more of the technical details. \=_{na_
92 * LightTools Introductory Tutorial kbM3
"
Hd|7F'u=
HAPTER 5 Introduction to Backlight Design Q7W>qe%4
C As>_J=8} 3
1.Rotate and zoom the model to that you can see something like the illustration / X1 x
below: rtc9wu
. 6F e34n]m
2.To reveal the Property Zones: 8<Hf" M
a.Right-click in the Design View and select View Preferences to display this G37U6PuZi
dialog box. yj\Nkh
b.On the Visibility tab, click the Property Zone check box to turn it on. vh$%9ed
c.Click OK. WY r/oRO
You will see the wire frame rendering of the spherical bumps on the '*3h!l W1.
bottom surface, and a solid color above it. The solid color is the 3D texture #"B \U N
of the BEFs (brightness-enhancing films) built automatically by the utility.
