Backlight module
View Patent ↗An embodiment of the present invention relates to a backlight module comprising a back plate, a light guide plate provided on the back plate and a light source provided at a side of the light guide plate. A side and lower surface of the light guide plate facing the lamp tubes is a concave surface. The weight of the backlight module and the cost can be largely reduced without change of the light efficiency.
1. A backlight module, comprising:
a back plate;
a light guide plate provided on the back plate; and
a light source provided at a side of the light guide plate, wherein a side and lower surface of the light guide plate facing the light source comprises a concave surface, and
wherein a side surface of the back plate facing the side and lower surface of the light guide plate comprises at lease one inclined surface, and the inclined surface is an inclined planar surface parallel to an axis of the light source, wherein a contour of the concave surface satisfies the following formula:
y
=
{
ax
4
+
bx
3
+
cx
2
+
dx
+
e
;
(
0
<
x
<
m
,
a
>
0
,
e
>
0
)
h
max
;
(
m
≤
x
≤
n
)
aX
4
+
bX
3
+
cX
2
+
dX
+
e
;
(
n
<
x
≤
L
max
,
X
=
L
max
-
x
,
a
>
0
,
e
>
0
)
wherein, x is a length of an upper surface of the light guide plate in an x direction, y is a thickness of the light guide plate; h max is the maximum thickness of the light guide plate in the y direction; h mid is the minimum thickness of the light guide plate in the y direction, which, in actual production, generally is not 0; L max is the maximum length of the upper surface of the light guide plate in the x direction.
2. The backlight module of claim 1 , wherein the side and lower surface of the light guide plate comprises at least two concave surfaces, and the light source is disposed in one of the concave surfaces.
3. The backlight module of claim 2 , wherein the at least two concave surfaces comprise a first concave surface adjacent to a side surface of the light guide plate and a second concave surface adjacent to a lower surface of the light guide plate, and the light source is disposed in the first concave surface.
4. The backlight of claim 3 , wherein the first and the second concave surfaces are concave surfaces having an arc-shaped cross section.
5. The backlight module of claim 1 , wherein an angle between the inclined planar surface and a lower surface of the back plate is in the range of 0°˜45°.
6. The backlight module of claim 1 , wherein an inner surface of the back plate facing the light guide plate is a mirror polished surface.
7. The backlight module of claim 1 , wherein the inclined surface is a curved surface.
8. The backlight module of claim 1 , wherein an inner surface of the back plate facing the light guide plate is a mirror polished surface.
9. The backlight module of claim 1 , wherein the light source is selected from the group consisting of a cold cathode fluorescent lamp, a hot cathode fluorescent lamp, and a light emitting diode.