TW201712266A - Backlight module - Google Patents

Abstract

A backlight module includes a lamp box, at least one light bar and at least one optical film. The light box has a bottom portion and a light-emitting side opposite to the bottom portion. The light bar is disposed on the bottom portion of the light box, wherein the light bar includes a substrate, a plurality of light emitting diode package structures and a plurality of lens. The light emitting diode package structures are disposed on the substrate. The lens are disposed on the substrate and respectively corresponding to the light emitting diode package structures. The optical film is disposed at the light-emitting side of the light box.

Description

Backlight module

The present invention relates to a backlight module, and more particularly to a backlight module using a light emitting diode as a light source.

At present, the light-emitting diode has been applied to the backlight module of the display, that is, the light-emitting diode is used as the light source of the backlight module. However, since the light-emitting diode point source has strong directivity, the light emitted by the light-emitting diode can be uniformly mixed to form a uniform surface light source, and the diffusion sheet disposed above the light-emitting diodes is often A sufficient distance from these light-emitting diodes is required. As a result, the light box cannot be further thinned, which means that the overall thickness of the backlight module can no longer be reduced, thereby affecting the development of thinning of the display.

In addition, since the light beam emitted by the light emitting diode has a divergence angle, there is a dark area between the adjacent two light emitting diodes, and these dark areas will cause the surface light source provided by the backlight module to have uniform light output. Degree drops. In order to solve the above problems, the industry has proposed to increase the number of use of the light-emitting diodes, and to shorten the spacing between adjacent two light-emitting diodes to reduce the area of the dark regions. However, the above method can effectively reduce the area of the dark area, but it increases the production cost of the backlight module. Therefore, how to effectively improve the light output uniformity of the backlight module and reduce the production cost has become an urgent problem to be solved.

The invention provides a backlight module, which can reduce the number of use of the LED package structure, reduce the cost and have better light uniformity.

The backlight module of the present invention comprises a light box, at least one light bar and at least one optical film. The light box has a bottom and a light exiting side relative to the bottom. The light bar is disposed at the bottom of the light box, wherein the light bar comprises a substrate, a plurality of light emitting diode package structures and a plurality of lenses. The light emitting diode package structure is disposed on the substrate. The lenses are disposed on the substrate and are respectively disposed corresponding to the LED package structure. The optical film is disposed on the light exit side of the light box.

In an embodiment of the invention, the substrate comprises a circuit board or an aluminum substrate.

In an embodiment of the invention, each of the light emitting diode package structures includes: a carrier substrate, a light emitting diode chip, a wavelength conversion layer, a transparent adhesive layer, and a resin colloid layer. The carrier substrate has an upper surface and a lower surface opposite to each other, a plurality of first pads disposed on the upper surface, and a plurality of second pads disposed on the lower surface. The light emitting diode chip is flipped on the carrier substrate, and has an active surface and a back surface opposite to each other, a side surface connecting the active surface and the back surface, and a plurality of electrode pads disposed on the active surface, wherein the light emitting diode The body wafer is electrically connected to the first pad through the electrode pads. The wavelength conversion layer is disposed on the back surface of the light emitting diode wafer and is disposed on the upper surface of the carrier substrate along a side surface of the light emitting diode wafer. The transparent adhesive layer is disposed on the wavelength conversion layer. The resin colloid layer is disposed on the carrier substrate and covers a surrounding surface of the transparent adhesive layer.

In an embodiment of the invention, the material of the carrier substrate includes ceramic, aluminum oxide, and aluminum nitride.

In an embodiment of the invention, the wavelength conversion layer comprises a yellow phosphor powder layer, a red phosphor powder layer, a green phosphor powder layer, a blue phosphor powder layer or a layer. Aluminum garnet fluorite powder layer.

In an embodiment of the invention, the material of the transparent adhesive layer comprises epoxy resin and silicone rubber.

In an embodiment of the invention, the resin colloid layer comprises an epoxy resin layer, a tantalum resin layer or a white rubber layer.

In an embodiment of the invention, each of the light emitting diode package structures includes: a light emitting diode chip, a wavelength conversion film, and a resin colloid layer. The light emitting diode chip is flipped on the substrate of the light bar, and has an active surface and a back surface opposite to each other, a side surface connecting the active surface and the back surface, and a plurality of electrode pads disposed on the active surface, wherein the light is emitted The diode chip is electrically connected to the substrate through an electrical pad. The wavelength converting film is disposed on the back surface of the light emitting diode wafer, wherein the wavelength converting film extends beyond the side surface of the light emitting diode wafer. The resin colloid layer coats a peripheral surface of the wavelength conversion film and is disposed along a side surface of the light emitting diode wafer.

In an embodiment of the invention, the wavelength conversion film comprises a yellow fluorescent powder film, a red fluorescent powder film, a green fluorescent powder film, a blue fluorescent powder film or a yttrium aluminum garnet phosphor powder. film.

In an embodiment of the invention, the resin colloid layer comprises an epoxy resin layer, a tantalum resin layer or a white rubber layer.

In an embodiment of the invention, each of the lenses has a lens portion, and the lens portion has a light incident surface and a light exit surface, and the radius of curvature of the light incident surface is greater than the radius of curvature of the light exit surface.

In an embodiment of the invention, each of the lenses further includes a plurality of supporting portions disposed between the lens portion and the substrate of the light bar.

In an embodiment of the invention, the optical film is a diffusion sheet.

In an embodiment of the invention, the at least one optical film is a two-diffusion sheet and a cymbal sheet, and the cymbal sheet is located between the diffusion sheets.

In an embodiment of the invention, the at least one optical film is a three-diffusion sheet and a cymbal sheet, and the cymbal sheet is located between any two diffusion sheets.

In an embodiment of the invention, each of the light emitting diode package structures has an illumination radius R, and an upper surface of the substrate of the light bar has an optical distance OD to a bottom surface of the optical film, and the lens A 1/2 divergence angle is θ, then R/OD = tan(θ).

In an embodiment of the invention, a distance P between the intermediate points of the adjacent two LED packages is an optimum value constant E between 1.7 and 2.3, then R=E*P .

In an embodiment of the invention, the light emitting diode package structures are arranged at equal intervals.

In an embodiment of the invention, the LED package structure is arranged at an unequal interval.

In an embodiment of the invention, a distance P between the intermediate points of the adjacent two LED packages is 0.9P<P<1.1P.

Based on the above, since the light emitting diode package structure of the present invention is disposed corresponding to the lens, the light beam emitted by the light emitting diode package structure can be uniformly dispersed, that is, the spacing between adjacent two light emitting diode package structures can be The large size can effectively reduce the number of use of the LED package structure, thereby effectively reducing the production cost of the backlight module and improving the uniformity of the light output of the backlight module.

The above described features and advantages of the invention will be apparent from the following description.

FIG. 1 is a schematic diagram of a backlight module according to an embodiment of the invention. Referring to FIG. 1 , in the embodiment, the backlight module 100 a includes a light box 110 , at least one light bar 120 , and at least one optical film 130 a . The light box 110 has a bottom portion 112 and a light exiting side 114 relative to the bottom portion 112. The light bar 120 is disposed at the bottom 112 of the light box 110. The light bar 120 includes a substrate 122, a plurality of light emitting diode package structures 124a, and a plurality of lenses 126. The LED package structure 124a is disposed on the substrate 122. The lens 126 is disposed on the substrate 122 and disposed corresponding to the LED package structure 124a. The optical film 130a is disposed on the light exiting side 114 of the light box 110. Here, the optical film 130a is, for example, a diffusion sheet, but is not limited thereto.

In detail, the substrate 122 of the light bar 120 is, for example, a circuit board or an aluminum substrate, and the light emitting diode package structures 124a are arranged on the substrate 122 at equal intervals, for example. As shown in FIG. 2A, each of the LED package structures 124a of the present embodiment includes a carrier substrate 124a1, a light emitting diode wafer 124a2, a wavelength conversion layer 124a3, a transparent adhesive layer 124a4, and a resin colloid layer 124a5. . The carrier substrate 124a1 has an upper surface 125a1 and a lower surface 125a2 opposite to each other, a plurality of first pads 125a3 disposed on the upper surface 125a1, and a plurality of second pads 125a4 disposed on the lower surface 125a2. The first pads The 125a3 is electrically connected to the second pad 125a4 through a conductive via (not shown) formed in the carrier substrate 124a1 or a metal layer (not shown) extending downward along the surface of the carrier substrate 124a1. The LED wafer 124a2 is flipped on the carrier substrate 124a1, and has an active surface 127a1 and a back surface 127a2 opposite to each other, a side surface 127a3 connecting the active surface 127a1 and the back surface 127a2, and a plurality of disposed on the active surface 127a1. The electrode pad 127a4 is electrically connected to the first pad 125a3 of the carrier substrate 124a1 through the electrode pad 127a4, and the LED package 124a is transmitted through the second pad 125a4 and the light bar 120. The substrate 122 is electrically connected. The wavelength conversion layer 124a3 is disposed on the rear surface 127a2 of the light emitting diode wafer 124a2, and is disposed on the upper surface 125a1 of the carrier substrate 124a1 along the side surface 127a3 of the light emitting diode wafer 124a2. The transparent adhesive layer 124a4 is disposed on the wavelength conversion layer 124a3 and conformally disposed with the wavelength conversion layer 124a3. The resin colloid layer 124a5 is disposed on the carrier substrate 124a1 and covers a peripheral surface 129a1 of the transparent adhesive layer 124a4.

More specifically, the material of the carrier substrate 124a1 of the LED package structure 124a of the present embodiment is, for example, ceramic, aluminum oxide, or aluminum nitride. The LED wafer 124a2 is flip-chip bonded to the carrier substrate 124a1. As shown in FIG. 2A, the electrode pads 127a4 of the LED wafer 124a2 are soldered to the first pads 125a3 of the carrier substrate 124a1 through the solder paste 128a. The wavelength conversion layer 124a3 and the transparent adhesive layer 124a4 are disposed on the back surface 127a2 of the LED wafer 124a2 by sequential spraying. The wavelength conversion layer 124a3 is, for example, a yellow phosphor powder layer and a red phosphor powder. The rubber layer, a green fluorescent powder layer, a blue phosphor powder layer or a layer of aluminum garnet phosphor powder, and the material of the transparent layer 124a4 is epoxy resin or silicone rubber. As shown in FIG. 2A, the wavelength conversion layer 124a3 completely covers the side surface 127a3 of the LED wafer 124a2 and extends over the edge of the electrode pad 127a4 and the edge of the first pad 125a3, while the transparent adhesive layer 124a4 completely covers the wavelength conversion. The layer 124a3 extends to the upper surface 125a1 of the carrier substrate 124a1. The resin colloid layer 124a5 is formed on the peripheral surface 129a1 of the transparent adhesive layer 124a4 by dispensing to cover the peripheral surface 129a1 of the transparent adhesive layer 124a4, and exposes a top surface 129a2 of the transparent adhesive layer 124a4. At the same time, the resin colloid layer 124a5 also fills the gap between the first pads 125a3 and the gap between the electrode pads 127a4. Here, the edge of the resin colloid layer 124a5 is substantially aligned with the edge of the carrier substrate 124a1, but is not limited thereto. The resin colloid layer 124a5 is, for example, an epoxy resin layer, a resin layer or a white rubber layer, which is disposed to block the lateral light of the LED array 124a2 and to emit the LED chip 124a2. The beam of light is uniform in color.

In another embodiment, referring to FIG. 1 and FIG. 2B simultaneously, in order to further reduce the cost, each of the LED package structures 124b may also be a light-emitting diode wafer 124b1, a wavelength conversion film 124b2, and a resin. The colloid layer 124b3 is composed of. The LED chip 124b1 is flipped on the substrate 122 of the light bar 120, and has an active surface 125b1 and a back surface 125b2 opposite to each other, a side surface 125b3 connecting the active surface 125b1 and the back surface 125b2, and a plurality of surfaces disposed on the active surface. The electrode pad 125b4 on the 125b1, wherein the LED chip 124b1 is electrically connected to the substrate 122 through the electrode pad 125b4. The wavelength conversion film 124b2 is disposed on the back surface 125b2 of the light emitting diode wafer 124b1, wherein the wavelength conversion film 124b2 extends beyond the side surface 125b3 of the light emitting diode wafer 124b1. That is, the side length of the wavelength conversion film 124b2 is larger than the side length of the light emitting diode wafer 124b1. Here, the wavelength conversion film 124b2 is, for example, a yellow fluorescent powder film, a red fluorescent powder film, a green fluorescent powder film, a blue fluorescent powder film or a yttrium aluminum garnet fluorescent film. The resin colloid layer 124b3 is dispensed to cover a peripheral surface 127b1 of the wavelength conversion film 124b2, and is disposed along the side surface 125b3 of the LED wafer 124b1, and exposes a top surface 127b2 of the wavelength conversion film 124b2. As shown in FIG. 2B, an encapsulant layer 128b is interposed between the resin colloid layer 124b3 and the side surface 125b3 of the LED wafer 124b1, wherein the encapsulant layer 128b completely covers the side surface 125b3 of the LED wafer 124b1, and the resin colloid The layer 124b3 extends over the encapsulation layer 128b to cover the peripheral surface 127b1 of the wavelength conversion film 124b2. . The resin colloid layer 124b3 is, for example, an epoxy resin layer, a tantalum resin layer or a white rubber layer.

Referring to FIG. 1, each lens 126 of the embodiment has a lens portion 126a, and the lens portion 126a has a light emitting surface 126a1 and a light incident surface 126a2. The radius of curvature of the light emitting surface 126a1 is smaller than the curvature of the light incident surface 126a2. The radius, and the outer surface of the central portion of the lens 126a is recessed toward the direction of the light source such that the peripheral contour of the cross section through the central portion of the lens 126a forms two peaks, and the intersection of the two peaks is the low point of the depression, and the depression is low Point the light source. In addition, each lens 126 can further have a plurality of support portions 126b, wherein the support portion 126b is disposed between the lens portion 126a and the substrate 122 of the light bar 120. As shown in FIG. 1, the LED package structure 124a of the present embodiment does not directly contact the lens 126, but has a gap S between the support portion 126b of the lens 126 and the lens portion 126a. In particular, the lens 126 of the present embodiment is disposed corresponding to the LED package structure 124a, and the purpose thereof is to uniformly disperse the light beam emitted by the LED package structure 124a.

More specifically, please refer to FIG. 3 , where the curve L1 in FIG. 3 is a relationship between the normalized light intensity and the divergence angle of the light-emitting diode package structure in which the lens is not provided, and the curve L2 is represented as an example. The light-emitting diode package structure 124a of the lens 126 is provided with a normalized light intensity versus divergence angle. Compared with the curve L1, the divergence angle of the curve L2 is widely distributed, that is, plus or minus 75 degrees, and the normalized light intensity is also distributed evenly, that is, the average is about 0.3. In this way, the spacing between the adjacent two LED package structures 124a can be increased, thereby effectively reducing the number of the LED package structures 124a, thereby effectively reducing the production of the backlight module 100a. The cost and the uniformity of light emission of the backlight module 100a can be improved.

Preferably, referring to FIG. 1, each of the LED package structures 124a has an illumination radius R, and an upper surface 122a of the substrate 122 of the light bar 120 has an optical surface to a bottom surface 132a of the optical film 130a. The distance OD, and a 1/2 divergence angle of the lens 126 is θ, then R/OD = tan(θ). Here, a distance P between the intermediate points of the adjacent two LED package structures 124a, an optimum value constant E is between 1.7 and 2.3, then R = E * P. That is to say, under the same optical distance OD, the larger the divergence angle of the lens 126 is, the larger the distance P is, and the number of the required light-emitting diode package structure 124a is reduced, which can effectively reduce the backlight module 100a. Cost of production. On the other hand, at the same distance P, the larger the divergence angle of the lens 126 is, the smaller the optical distance OD is. The thinner the thickness of the light box 110 is, the more effective the backlight module 100a can be. In short, the user can change the optical distance OD or the distance P through the above relationship to obtain the desired function of the backlight module 100a.

It is worth mentioning that the optimal value constant E defined above is aimed at adjusting the distance P to make the surface light source provided by the backlight module 100a look more uniform. In addition, if the distance P is too large, the brightness of the light beam emitted by the LED package structure 124a may be insufficiently bright. In this case, the number of power supply watts of the LED array 124a2 (refer to FIG. 2A) may be increased. The brightness is increased, which is also an advantage of the flip-chip light-emitting diode wafer 124a2.

Of course, this embodiment does not limit the arrangement of the LED package structures 124a. Referring to FIG. 4, in the embodiment, the backlight module 100b is similar to the backlight module 100a of FIG. 1, but the main difference is that the LED module of the backlight module 100b of the embodiment has a light-emitting diode package structure. 124c1, 124c2, 124c3, 124c4, and 124c5 are arranged on the substrate 122 at unequal intervals, wherein the structure of the LED package structures 124c1, 124c2, 124c3, 124c4, and 124c5 and the LED package structure 124a Or the LED package structure 124b is the same, and is not limited herein. Preferably, 0.9P < P < 1.1P. As shown in FIG. 4, the distance P1 between the LED package structure 124c3 and the LED package structure 124c2, or the distance P1 between the LED package structure 124c3 and the LED package structure 124c4. It is greater than the distance P2 between the LED package structure 124c1 and the LED package structure 124c2, or the distance P2 between the LED package structure 124c4 and the LED package structure 124c5. For example, the distance P1 is, for example, 1.1P, and the distance P2 is, for example, 0.9P, wherein the distance P is expressed as when the light emitting diode package structures 124a are arranged at equal intervals, the adjacent two light emitting diode package structures 124a. The distance between the middle points.

In the backlight module 100b of the present embodiment, the LED packages 124c1, 124c2, 124c3, 124c4, and 124c5 are arranged on the substrate 122 at unequal intervals, thereby widening the brightness of the center of the light box 110. In order to reduce the light intensity in the center of the light box 110 to complement the dark area at the edge of the light box 110, the backlight module 100b can provide a uniform ground light source. The backlight modules 100a and 100b described above are, for example, advertising light boxes.

Further, the present embodiment does not limit the number and type of the optical sheets 130a. Referring to FIG. 5, in the present embodiment, the backlight module 100c is similar to the backlight module 100a of FIG. 1, but the main difference between the two is that the optical film of the embodiment has three slices, which are respectively two. The diffusion sheets 130c1, 130c3 and a cymbal sheet 130c2 are disposed between the diffusion sheets 130c1, 130c3. Alternatively, please refer to FIG. 6. In this embodiment, the backlight module 100d is similar to the backlight module 100a of FIG. 1, but the main difference between the two is that the optical film of the embodiment has four pieces. The three diffusion sheets 130d1, 130d3, and 130d4 are respectively disposed between the diffusion sheets 130d1 and 130d3, but are not limited thereto. The backlight modules 100c and 100d described above are, for example, backlight modules of televisions.

In addition, this embodiment does not limit the radius of curvature of the light incident surface 126a2 of the lens 126. Please refer to FIG. 7A and FIG. 7B simultaneously, wherein FIG. 7A is the LED package structure 124a and the lens portion 126a of FIG. 1, and the LED package structure 124a of FIG. 7B and the LED package of FIG. 7A. The structure 124a is the same, and the main difference is that the radius of curvature of the light incident surface 126a2' of the lens portion 126a' in Fig. 7B is smaller than the radius of curvature of the light incident surface 126a2 of the lens portion 126a in Fig. 7A. As can be clearly seen from FIG. 7A and FIG. 7B, the radius of curvature of the light incident surface 126a2 of the lens portion 126a in FIG. 7A is relatively large, so that the light beam emitted by the light emitting diode package structure 124a is relatively divergent, and the lens in FIG. 7B is relatively dense. The light incident surface 126a2' of the portion 126a' has a small radius of curvature, so that the light beam emitted by the light emitting diode package structure 124a is concentrated. In short, the user can select the radius of curvature of the light incident surfaces 126a2, 126a2' of the lens portions 126a, 126a' according to the desired effect, and is not limited thereto.

In summary, the light emitting diode package structure of the present invention is disposed corresponding to the lens, so that the light beam emitted by the light emitting diode package structure can be uniformly dispersed, that is, between adjacent two light emitting diode package structures. The pitch is increased, thereby effectively reducing the number of used LED package structures, thereby effectively reducing the production cost of the backlight module and improving the uniformity of the backlight module.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

100a, 100b, 100c, 100d‧‧‧ backlight module
110‧‧‧Lightbox
112‧‧‧ bottom
114‧‧‧Lighting side
120‧‧‧light strips
122‧‧‧Substrate
122a‧‧‧ upper surface
124a, 124b, 124c1, 124c2, 124c3, 124c4, 124c5‧‧‧Light emitting diode package structure
124a1‧‧‧bearing substrate
124a2, 124b1‧‧‧Light Emitter Wafer
124a3‧‧‧wavelength conversion layer
124a4‧‧‧Transparent rubber layer
124a5, 124b3‧‧‧ resin colloid layer
124b2‧‧‧ wavelength conversion film
125a1‧‧‧ upper surface
125a2‧‧‧ lower surface
125a3‧‧‧first mat
125a4‧‧‧second mat
126‧‧‧ lens
126a, 126a'‧‧‧ lens section
126a1‧‧‧Glossy surface
126a2, 126a2'‧‧‧ into the glossy surface
126b‧‧‧Support
127a1, 125b1‧‧‧ active surface
127a2, 125b2‧‧‧ back surface
127a3, 125b3‧‧‧ side surface
127a4, 125b4‧‧‧ electrode pads
128a‧‧‧ solder paste
128b‧‧‧Package layer
129a1, 127b1‧‧‧ surrounding surface
129a2, 127b2‧‧‧ top surface
130a‧‧‧Optical diaphragm
130c1, 130c3, 130d1, 130d3, 130d4‧‧‧ diffuser
130c1, 130d2‧‧‧ pictures
132a‧‧‧ bottom surface
L1, L2‧‧‧ curve
P, P1, P2‧‧‧ distance
R‧‧‧Lighting radius
S‧‧‧ gap
OD‧‧‧ optical distance θ‧‧‧1/2 divergence angle

FIG. 1 is a schematic diagram of a backlight module according to an embodiment of the invention. FIG. 2A is an enlarged schematic view showing a light emitting diode package structure of FIG. 1. FIG. 2B is an enlarged schematic view showing a light emitting diode package structure in another embodiment. 3 is a graph showing the relationship between the normalized light intensity and the divergence angle of a light-emitting diode package structure of FIG. 1 corresponding to a lens. FIG. 4 is a schematic diagram of a backlight module according to another embodiment of the invention. FIG. 5 is a schematic diagram of a backlight module according to another embodiment of the invention. FIG. 6 is a schematic diagram of a backlight module according to another embodiment of the invention. 7A and FIG. 7B are schematic diagrams showing light paths of the light incident surface of the lens having different radii of curvature and light beams emitted by the light emitting diode package structure.

100a‧‧‧Backlight module

110‧‧‧Lightbox

112‧‧‧ bottom

114‧‧‧Lighting side

120‧‧‧light strips

122‧‧‧Substrate

122a‧‧‧ upper surface

124a‧‧‧Light Emitting Diode Structure

126‧‧‧ lens

126a‧‧‧Lens Department

126a1‧‧‧Into the glossy surface

126a2‧‧‧Glossy surface

126b‧‧‧Support

130a‧‧‧Optical diaphragm

132a‧‧‧ bottom surface

P‧‧‧ distance

R‧‧‧Lighting radius

S‧‧‧ gap

OD‧‧‧ optical distance

Θ‧‧‧1/2 divergence angle

Claims (10)

A backlight module includes: a light box having a bottom and a light exiting side opposite to the bottom; at least one light strip disposed at the bottom of the light box, wherein the light strip comprises: a substrate; a plurality of light emitting diodes The body package structure is disposed on the substrate; and a plurality of lenses are disposed on the substrate and respectively disposed corresponding to the light emitting diode package structures; and at least one optical film is disposed on the light exiting side of the light box. The backlight module of claim 1, wherein each of the light emitting diode package structures comprises: a carrier substrate having an upper surface and a lower surface opposite to each other, and a plurality of the first surface disposed on the upper surface a pad and a plurality of second pads disposed on the lower surface; a light emitting diode chip overlying the carrier substrate and having an active surface opposite to each other and a back surface a side surface of the back surface and a plurality of electrode pads disposed on the active surface, wherein the light emitting diode chip is electrically connected to the first pads through the electrode pads; a wavelength conversion layer, configured On the back surface of the light-emitting diode wafer, and extending along the side surface of the light-emitting diode wafer on the upper surface of the carrier substrate; a transparent adhesive layer disposed on the wavelength conversion layer; And a resin colloid layer disposed on the carrier substrate and covering a surrounding surface of the transparent adhesive layer. The backlight module of claim 1, wherein each of the light emitting diode package structures comprises: a light emitting diode chip, which is overlaid on the substrate of the light bar and has an active opposite to each other a surface and a back surface, a side surface connecting the active surface and the back surface, and a plurality of electrode pads disposed on the active surface, wherein the light emitting diode chip is electrically connected to the substrate through the electrode pads; a wavelength conversion film disposed on the back surface of the light emitting diode chip, wherein the wavelength conversion film extends beyond the side surface of the light emitting diode wafer; and a resin colloid layer covering the wavelength conversion film a surrounding surface disposed along the side surface of the light emitting diode wafer. The backlight module of claim 1, wherein each of the lenses has a lens portion, and the lens portion has a light incident surface and a light exit surface, and a radius of curvature of the light incident surface is greater than the light exit surface Radius of curvature. The backlight module of claim 4, wherein each of the lenses further has a plurality of supporting portions disposed between the lens portion and the substrate of the light bar. The backlight module of claim 1, wherein the at least one optical film is a two-diffusion sheet and a cymbal sheet, and the cymbal sheet is located between the diffusion sheets. The backlight module of claim 1, wherein each of the light emitting diode package structures has an illumination radius R, and an upper surface of the substrate of the light bar has a bottom surface of the optical film. An optical distance OD, and a 1/2 divergence angle of the lens is θ, then R / OD = tan (θ). The backlight module of claim 7, wherein a distance P between adjacent points of the two adjacent LED package structures has an optimum value constant E between 1.7 and 2.3. Then R = E * P. The backlight module of claim 1, wherein the light emitting diode packages are arranged at unequal intervals. The backlight module of claim 9, wherein a distance P between two intermediate points of the two adjacent light emitting diode packages is 0.9P<P<1.1P.