TWI393923B - Prism sheet and backlight module using the same - Google Patents

Description

Backlight module and its chip

The invention relates to a backlight module and a cymbal thereof, in particular to a backlight module for liquid crystal display and a cymbal thereof.

Referring to FIG. 1 , a conventional direct type backlight module 100 includes a frame 11 , a plurality of light sources 12 disposed inside the frame 11 , a diffusion plate 13 disposed above the light source 12 and covering the frame 11 , and A piece of film 10. The diffusing plate 13 generally contains scattering particles for diffusing light. The cymbal 10 includes a light incident surface 101 for receiving a light beam, a light exit surface 103 opposite to the light incident surface 101, and a plurality of elongated V-shaped projections 105 formed on the light exit surface 103.

In use, after the light generated by the complex light source 12 is uniformly diffused into the diffusing plate 13, it continues to enter the cymbal 10, and the emitted light is concentrated to some extent under the action of the elongated V-shaped projection 105 of the cymbal 10. Thereby, the brightness of the backlight module 100 within a certain viewing angle range is improved.

Referring to FIG. 2 and FIG. 3 together, the light becomes uniform after being diffused by the diffusion plate 13, but the angle at which the scattered light is incident on the cymbal 10 becomes disordered. The disordered light enters the cymbal 10 and exits at the interface of the V-shaped protrusion 105. Part of the emitted light (such as a1, a2) is concentrated in a direction close to the vertical direction (ie, parallel to the Y-axis), and the portion of the emitted light can be emitted. Increasing the brightness of the front surface of the backlight module 100; however, part of the emitted light (eg, a3, a4) is emitted toward the horizontal direction (X-axis direction) at the interface of the V-shaped protrusion 105, and the portion of the emitted light is not effectively utilized; There is still some light (such as a5, a6) which is refracted at the interface of the V-shaped protrusion 105 and then re-entered into the cymbal 10, in which the light energy loss is large. In addition, the plurality of V-shaped protrusions 105 of the cymbal 10 are arranged in parallel, and the light is concentrated. Mainly occurs in a plane perpendicular to the extending direction of the V-shaped protrusion 105, and the light of a plane parallel to the extending direction of the V-shaped protrusion 105 does not aggregate, so that the portion of the light is not effectively utilized.

In view of the above situation, it is necessary to provide a backlight module and a chip which can improve the effective utilization of light and high brightness.

A cymbal sheet consisting of a transparent body comprising a first surface and a second surface opposite the first surface. The first surface of the transparent body has a plurality of circular trough-shaped grooves, and the second surface of the transparent body has a plurality of micro-grooves, each micro-groove includes four inner sides sequentially connected, and the horizontal width of each inner side is from The second surface tapers inwardly.

A backlight module includes a light source, a diffusion plate and a cymbal plate. The diffusion plate and the cymbal plate are sequentially disposed above the light source. The cymbal piece is composed of a transparent body, and the transparent body includes a first surface and the first The surface is opposite the second surface. The first surface of the transparent body has a plurality of circular trough-shaped grooves, and the second surface of the transparent body has a plurality of micro-grooves, each micro-groove includes four inner sides sequentially connected, and the horizontal width of each inner side is from The second surface tapers inwardly.

The first surface of the cymbal has a plurality of circular truncated grooves, and the second surface has a plurality of micro-grooves. The plurality of dimples on the first surface have a varying curved surface structure, and the plurality of dimples of the second surface The groove has an inclined surface structure, and the curved surface structure cooperates with the inclined surface structure to cooperate with the light incident on the cymbal, so that the backlight module using the cymbal can improve the effective utilization of light and the brightness of the emitted light.

(this invention)

200‧‧‧Backlight module

20, 30, 40, 50‧‧‧ pictures

201, 401, 501‧‧‧ first surface

202, 302‧‧‧ second surface

203, 403, 503‧‧‧ round table groove

204, 304‧‧‧ micro-groove

3041‧‧‧ micro groove bottom

3042‧‧‧ micro groove notch

21‧‧‧Diffuser

22‧‧‧Light source

23‧‧‧Frame

FIG. 1 is a schematic cross-sectional view of a conventional backlight module.

2 is a perspective view of a cymbal of the backlight module shown in FIG. 1.

Fig. 3 is a schematic view showing the light exiting along the line III-III of the cymbal shown in Fig. 2.

4 is a cross-sectional view of a backlight module in accordance with a preferred embodiment of the present invention.

FIG. 5 is a perspective view of the cymbal of the backlight module shown in FIG. 4.

6 is a top plan view of the cymbal of the backlight module shown in FIG. 4.

Figure 7 is a plan view of a cymbal sheet of the preferred embodiment 2 of the present invention.

Figure 8 is a bottom plan view of a third embodiment of the preferred embodiment of the present invention.

Figure 9 is a bottom plan view of the cymbal of the preferred embodiment of the present invention.

The backlight module and the cymbal of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

Referring to FIG. 4 , a backlight module 200 according to a preferred embodiment of the present invention includes a cymbal 20 and a diffusion plate 21 disposed on one side of the cymbal 20 , a plurality of light sources 22 , and a plurality of light sources 22 . Frame 23. The crotch panel 20 and the diffuser plate 21 cover the frame 23. The light emitted from the light source 22 is reflected directly or by the frame 23 into the diffusing plate 21, diffused through the diffusing plate 21, and then enters the cymbal 20 to be collected.

Referring to FIG. 5, the cymbal 20 is formed by a transparent body including a first surface 201 and a second surface 202 opposite the first surface 201. The first surface 201 has a plurality of truncated-shaped grooves 203, and the second surface 202 has a plurality of micro-grooves 204.

Referring to FIG. 4 and FIG. 5 simultaneously, the first surface 201 faces the diffusion plate 21, and the truncated cone-shaped recess 203 is used to converge the light incident on the cymbal 20. The plurality of truncated grooves 203 are arranged in a regular array. The distance P between the centers of the adjacent truncated grooves 203 is 0.025 mm to 1.5 mm. The maximum radius R of each of the truncated grooves 203 is P/4 to P; the angle θ between the inner side of each truncated groove 203 and the center line of the truncated groove 203 is 30 to 75 degrees. That is, when the center of the adjacent truncated groove 203 is When the distance P is from 0.025 mm to 1.5 mm, the maximum radius R of each of the truncated grooves 203 may be from 0.006 mm to 1.5 mm. In this embodiment, the maximum radius R of the truncated-shaped groove 203 is equal to P/2, that is, the plurality of truncated-shaped grooves 203 are closely arranged in a regular array in this embodiment.

Referring to FIGS. 4 and 6, the second surface 202 faces away from the diffuser plate 21, and the micro-grooves 204 are used to collect the light emitted from the cymbal 20. The plurality of micro-grooves 204 are arranged closely in a regular array. Each of the micro-grooves 204 includes four inner side faces that are sequentially connected, and the inner side faces of the micro-grooves 204 are two opposite-isometric four-isometric triangles, that is, the micro-grooves 204 have a quadrangular pyramid shape. The angle formed by the opposite sides of the micro-grooves 204 is equal and the angle ranges from 60 degrees to 120 degrees. In the X direction, the center distance X ₁ between adjacent micro grooves 204 is 0.025 mm to 1 mm; in the Y direction, the center distance Y ₁ between adjacent micro grooves 204 is 0.025 mm to 1 mm. It can be understood that the angle formed by the opposite sides of the micro-grooves 204 may not be equal. By adjusting the angle of the angle and the aspect ratio of the micro-grooves 204, the brightness enhancement and the light-emitting angle of the cymbal 20 can be adjusted. .

The overall thickness of the crotch panel 20 can range from 0.5 mm to 3 mm. The cymbal sheet 20 may be injection molded from one or more of polymethyl methacrylate, polycarbonate, polystyrene, and styrene-methyl methacrylate copolymer. During the preparation process, a convex structure corresponding to the truncated cone-shaped recess 203 and the micro-groove 204 is provided on the mold, so that the cymbal sheet 20 can be formed in a single injection molding process.

Light source 22 can be a line source or a point source, such as a light emitting diode and a cold cathode fluorescent lamp.

The frame 23 may be made of metal or plastic having high reflectivity or metal or plastic coated with a high reflectivity coating.

Since the plurality of truncated-shaped grooves 203 on the first surface 201 have a varying curved surface structure, the plurality of micro-grooves 204 of the second surface 202 have an inclined surface structure, and the curved surface structure cooperates with the inclined surface structure to cooperate The light incident on the cymbal 20 is easy to make the backlight module 200 using the cymbal 20 improve the effective utilization of light and the brightness of the emitted light.

Specifically, in the embodiment, when the light enters the cymbal 20 from the first surface 201, since the first surface has a plurality of circular truncated grooves 203, the curved surface structure of the truncated concave 203 gradually changes the ray to be perpendicular to the rib. The direction of the lens 20 converges to some extent; when the light exits from the second surface 202, since the second surface 202 has a plurality of micro-grooves 204, the surface structure of the micro-grooves 204 is inclined such that the outgoing light is perpendicular to the cymbal 20. Further gathering, so that the brightness of the outgoing light of the backlight module 200 can be greatly improved. At the same time, since the first surface 201 converges most of the light to a direction perpendicular to the cymbal 20 when the light enters the cymbal 20, when the light is emitted from the second surface 202, it is parallel to the cymbal 20. Less light is emitted, which reduces the light that is returned to the cymbal 20 again and allows more light to be effectively utilized.

Further, since the micro-grooves 204 of the second surface 202 are quadrangular pyramid-shaped, and have four inner sides connected in sequence, the outgoing light can be effectively concentrated regardless of the XZ plane or the YZ plane, thereby making full use of The light in all directions further increases the brightness of the light emitted from the front surface of the backlight module 200.

In addition, the cymbal sheet 20 is integrally formed by injection molding, and the conventional cymbal sheet is formed by coating a transparent film with a resin film forming microstructure, and the cymbal sheet 20 is easier to achieve rapid mass production and lower cost. In addition, when used, there is no light interface loss in the cymbal 20, and the light utilization rate is higher. In addition, the conventional method applies a resin film forming microstructure on a transparent plate, and since the bonding force between the coated resin film and the transparent plate is generally low and the resin film itself is difficult to form high strength, the microstructure is easily scratched and pressed. The ruthenium 20 formed by injection molding has a truncated groove 203 and a micro groove 204 formed together with other portions of the cymbal 20, so that the truncated groove 203 and the micro groove 204 can be compared. The high structural strength can also improve the bonding force between the truncated cone-shaped recess 203 and the micro-groove 204 and other portions of the cymbal 20, so that the truncated-shaped recess 203 and the micro-groove 204 can be avoided or reduced. 20 Risk of damage during use.

It can be understood that the second surface 202 can also be used to face the diffusion plate 21, and the first surface 201 is extended toward the surface. Dispersion plate 21.

Referring to Figure 7, there is shown a die 30 of a preferred embodiment of the present invention. The cymbal sheet 30 is similar to the cymbal sheet 20 of the first embodiment except that the micro-grooves 304 of the second surface 302 are quadrangular-shaped, and the shape of the groove bottom 3041 and the notch 3042 are square, and the micro-grooves 304 Arranged in regular arrays. It can be understood that the shape of the groove bottom 3041 and the notch 3042 of the micro groove 304 can also be a rectangle.

Referring to Figure 8, there is shown a third embodiment of a third embodiment of the present invention. The cymbal 40 is similar to the cymbal 20 of the first embodiment except that the truncated grooves 403 of the first surface 401 are closely staggered in an array.

Referring to Figure 9, there is shown a topsheet 50 of a preferred embodiment of the present invention. The crotch panel 50 is similar to the crotch panel 20 of the first embodiment except that the truncated grooves 503 of the first surface 501 are arranged in a random arrangement.

It can be understood that, in the above-mentioned cymbal, the truncated-shaped grooves of the first surface may be arranged in an array or arranged symmetrically with respect to the center of the cymbal, and are arranged in a circular shape in the array arrangement. The direction in which the grooves are arranged may also form an acute angle with the sides of the crotch. Similarly, the microgrooves of the second surface may also have a similar arrangement to the truncated cones.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. However, the above description is only the preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiments, and those skilled in the art will be equivalently modified or changed in the spirit of the invention. All should be included in the scope of the following patent application.

200‧‧‧Backlight module

20‧‧‧ Picture

201‧‧‧ first surface

202‧‧‧ second surface

203‧‧‧round table groove

204‧‧‧Microgroove

21‧‧‧Diffuser

22‧‧‧Light source

23‧‧‧Frame

Claims (17)

A cymbal sheet is a transparent body, the transparent body includes a first surface and a second surface opposite to the first surface, and the improvement is that the first surface of the transparent body has a plurality of circular truncated grooves, the transparent The second surface of the body has a plurality of micro-grooves, each micro-groove comprising four inner sides sequentially connected, and the horizontal width of each inner side gradually decreases inward from the second surface. The cymbal according to claim 1, wherein the center-to-center spacing of the adjacent truncated grooves is 0.025 mm to 1.5 mm; the maximum radius of each truncated groove is 0.006 mm to 1.5 mm; The angle between the inner side surface of the groove and the center line of the truncated groove is 30 to 75 degrees. The cymbal of claim 1, wherein the plurality of micro-grooves are quadrangular pyramid-shaped grooves or quadrangular-shaped grooves. The cymbal of claim 3, wherein the angle between the two opposite inner sides of each micro-groove is 60 degrees to 120 degrees. The cymbal according to claim 1, wherein the center spacing of the adjacent micro grooves is 0.025 mm to 1 mm. The bracts of claim 1, wherein the bracts have a thickness of from 0.5 mm to 3 mm. The cymbal of claim 1, wherein the plurality of circular troughs and the plurality of micro-grooves are arranged in an array. The bracts of claim 1, wherein the bracts are one or more of polymethyl methacrylate, polycarbonate, polystyrene, styrene-methyl methacrylate copolymer. The material is injection molded. A backlight module includes a light source, a diffusion plate and a cymbal piece, and the diffusion plate and the cymbal piece are in turn Provided above the light source, the cymbal piece is formed by a transparent body, the transparent body comprises a first surface and a second surface opposite to the first surface, and the improvement is that the first surface of the transparent body has a plurality of round tables The second surface of the transparent body has a plurality of micro-grooves, each micro-groove includes four inner sides sequentially connected, and a horizontal width of each inner side gradually decreases inward from the second surface. The backlight module of claim 9, wherein the first surface faces the diffusion plate. The backlight module of claim 9, wherein a center-to-center spacing of the adjacent truncated-shaped grooves is 0.025 mm to 1.5 mm; and a maximum radius of each of the truncated-shaped grooves is 0.006 mm to 1.5 mm; The angle between the inner side surface of a circular truncated groove and the center line of the truncated groove is 30 to 75 degrees. The backlight module of claim 9, wherein the plurality of micro-grooves are quadrangular pyramid-shaped grooves or quadrangular-shaped grooves. The backlight module of claim 12, wherein an angle between two opposite inner sides of each micro-groove is 60 degrees to 120 degrees. The backlight module of claim 9, wherein the center spacing of the adjacent micro grooves is 0.025 mm to 1 mm. The backlight module of claim 9, wherein the ruthenium has a thickness of 0.5 mm to 3 mm. The backlight module of claim 9, wherein the plurality of circular truncated grooves and the plurality of micro-grooves are arranged in an array. The backlight module of claim 9, wherein the cymbal sheet is one or more of polymethyl methacrylate, polycarbonate, polystyrene, and styrene-methyl methacrylate copolymer. The material is injection molded.