The default number of bumps is 100 (10 X 10). You need to change these XC3)#D#HGh
parameters to match your design. Note that LightTools allows many other c^ W;p2^
placement options, but you will use the Bezier placement option for this ]t 0o%w
example. u#ya
8
5.On both the X Placement tab and Y Placement tab, change the Number of 8-G )lyfj
Bumps parameter to 300, as shown in the following figure. Click Apply after =zn'0g, J4
each change. gN/!w:
6.Click OK to close the dialog box. Y][12{I{
Note that the number of bumps is 300 X 300, which results in about 90,000 VD.TosVeWo
bumps on the surface (~ 5143 bumps/in2). These bumps are arranged in a VN)WBv
manner defined by the Bezier parameterization option. Please see Chapter 5 of g clj:7U
the LightTools Core Module User’s Guide for more information. With the u$JAjA
current parameter values, the Bezier option varies the bump spacing along the sV"tN2W@
length of the light guide. The spacing in the orthogonal direction is constant. 4u5j
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The X and Y refer to the local coordinate system of the surface. (XOz_K6c%K
LightTools Introductory Tutorial * 91 < J^5l0)q
5RLO}Vn ]
HAPTER 5 Introduction to Backlight Design 7@{%S~T N
C v6)QLp
Examining Surface Properties '
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Using the methods described in previous chapters, you may want to check your " W5MZ
model before you run a simulation. V ESvCei
Click on various parts of the model in the 3D Design View. Or use the System = o(}=T>:"
Navigator to select different surfaces and view their Properties. @* hv|zjs
1.In the System Navigator, click to open BottomSurface of the LightGuide, then Qy:yz
click Zones, and then click Texture. ~ |Kq G
2.Select SphericalElement, and then right-click and select Properties from the ~?NCmU=3
shortcut menu. The Shape tab shows you a graphical representation of the 0eO!,/
spherical bump shape that is the bottom of the light guide. s`x2Go
You might be curious as to why you cannot see the 3D texture property zones you 0Px Hf*
defined. They are invisible by default, because drawing thousands of texture !hHe`
elements can make displaying and exploring the model somewhat slow. If you g Nr4oOR{
choose to make them visible, 3D textures are displayed in wireframe, even if the ^ ?e[$}
display mode is set to translucent. Wireframe rendering displays a bit faster and \ gP?uJ
shows more of the technical details. pqg2#@F.
92 * LightTools Introductory Tutorial cEHpa%_5
_L8&.=4]i
HAPTER 5 Introduction to Backlight Design [
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C Xf;!w:u
1.Rotate and zoom the model to that you can see something like the illustration "*zDb|v
below: 54z`KX
73
. l z=D Gm
2.To reveal the Property Zones: bAt!S
a.Right-click in the Design View and select View Preferences to display this Rc)]A&J
dialog box. b#7nt ?`7p
b.On the Visibility tab, click the Property Zone check box to turn it on. 0fa f4LzU!
c.Click OK. 5^uX!_ r`
You will see the wire frame rendering of the spherical bumps on the K 14.!m
bottom surface, and a solid color above it. The solid color is the 3D texture zDYJe_m ~
of the BEFs (brightness-enhancing films) built automatically by the utility.
