CN101936488B - Backlight module - Google Patents

Abstract

The invention discloses a backlight module which comprises a light guide plate and a plurality of light-emitting components. The light guide plate is provided with an incidence surface and an emergence surface which is provided with a visible area, the light-emitting components are arranged on the incidence surface of the light guide plate, and each light-emitting component is provided with a light emission surface and an optical shaft perpendicular to the light emission surface. The optical shafts are approximately crossed in a center point of the visible area.

Description

Backlight module

Technical field

The present invention relates to a kind of backlight module, and particularly relevant for a kind of backlight module that improves overall brightness.

Background technology

In general, liquid crystal indicator has comprised display panels and backlight module usually, and wherein backlight module mainly is to be used to provide display panels required area source when showing.

Fig. 1 is the schematic top plan view of known a kind of backlight module, wherein explanation for ease, and Fig. 1 only illustrates the interior light emitting diode of backlight module and the relative position of LGP, does not illustrate to be positioned at LGP blooming piece up and down.Please refer to Fig. 1, backlight module 100 includes a plurality of light emitting diodes 110 and a LGP 120.LGP 120 has long limit and minor face; And light emitting diode 110 normally is arranged in long limit or the minor face of LGP 120 with the light emitting source as backlight module 100; Wherein Fig. 1 illustrates the minor face that light emitting diode 110 is arranged in LGP 120; In other words, this minor face is an incidence surface 122 of LGP 120.

Each light emitting diode 110 has an optical axis 114 of a light emitting surface 112 and a vertical light surface of emission 112.In detail, the arrangement mode that light emitting diode 110 is disposed at the minor face of LGP 120 is generally straight line parallel and distributes, and promptly the optical axis 112 of each light emitting diode 110 is for being parallel to each other, and is as shown in Figure 1.

Because the lighting angle of light emitting diode 110 is about 110 degree usually; And it is as shown in Figure 1 that light emitting diode 110 is disposed at the arrangement mode of minor face of LGP 120; Therefore; The refraction number of times of the light that light emitting diode 110 provides in LGP can be lower, and the light path that is incident in LGP 120 also can be along with being easy to outside the dispersion light-guiding board 120 near the edge of LGP 120, and then reduce the light utilization of light emitting diode 110.Thus, the overall brightness of backlight module 100 will be difficult to obtain lifting.

Summary of the invention

In view of this, the present invention provides a kind of backlight module, and it can concentrate the light that is incident in LGP, and can promote the refraction number of times of light in LGP, and has preferable overall brightness.

The present invention proposes a kind of backlight module, and it comprises a LGP and a plurality of light-emitting component.LGP has an incidence surface and an exiting surface, and wherein exiting surface has a visible area.Light-emitting component is arranged on the incidence surface of LGP, and wherein each light-emitting component has a light emitting surface and an optical axis vertical with light emitting surface.These optical axises roughly intersect at the central point of visible area.

In one embodiment of this invention, the incidence surface of LGP is provided with the odd number light-emitting component.

In one embodiment of this invention, visible area has a width X in the horizontal direction and has a length Y in vertical direction.Has an angle theta between the optical axis of each light-emitting component and the vertical direction of visible area _mFor:

${\mathrm{\θ}}_m={\tan }^{-1}\left|\left(\frac{(2m+\mathrm{\σ})X}{(2n+1)Y}\right)\right|$

Wherein, the incidence surface of LGP is provided with 2n+1 light-emitting component, and n ≠ 0, and m is the positive integer of 0～n, and-1＜σ＜1.

In one embodiment of this invention, visible area has a width X in the horizontal direction and has a length Y in vertical direction.Visible area has a center line in vertical direction, and has one apart from d between each light-emitting component of along continuous straight runs and the center line _mFor:

$d_m=\left|(1+\frac{2a}{Y})(m+\mathrm{\σ})\frac{X}{2n+1}\right|$

Wherein, the incidence surface of LGP is provided with 2n+1 light-emitting component, n ≠ 0, and m is the positive integer of 0～n, a is the distance at edge of incidence surface to the visible area of LGP, and-0.5＜σ＜0.5.

In one embodiment of this invention, the incidence surface of LGP is provided with the even number light-emitting component.

In one embodiment of this invention, visible area has a width X in the horizontal direction and has a length Y in vertical direction, has an angle theta between the optical axis of each light-emitting component and the vertical direction of visible area _mFor:

${\mathrm{\θ}}_m={\mathrm{Tan}}^{-1}\left|\left(\frac{((2m-1)+\mathrm{\σ})X}{2\mathrm{NY}}\right)\right|,$ And θ _m≠ 0

Wherein, the incidence surface of LGP is provided with 2n light-emitting component, and n ≠ 0, and m is the positive integer of 1～n, and-0.5＜σ＜0.5.

In one embodiment of this invention, visible area has a width X in the horizontal direction and has a length Y in vertical direction.Visible area has a center line in vertical direction, and has one apart from d between each light-emitting component of along continuous straight runs and the center line _mFor:

$d_m=\left|(1+\frac{2a}{Y})((2m-1)+\mathrm{\σ})\frac{X}{4n}\right|,$ And d _m≠ 0

Wherein, the incidence surface of LGP is provided with 2n light-emitting component, n ≠ 0, and m is the positive integer of 1～n, a is the distance at edge of incidence surface to the visible area of LGP, and-1＜σ＜1.

In one embodiment of this invention, have a plurality of grooves on the incidence surface of LGP, and be placed with a light-emitting component in each groove.

In one embodiment of this invention, visible area has a center line in vertical direction, and groove has an angle of inclination respectively, and more little the closer to the angle of inclination of the groove of the center line of LGP.

In one embodiment of this invention, backlight module more comprises an optical diaphragm group and a reflector plate.Optical diaphragm group is arranged at the top of the exiting surface of LGP.Reflector plate is arranged on the surface of exiting surface subtend of LGP.

Based on above-mentioned; The optical axis intersection of the backlight module of present embodiment through making each light-emitting component is in the central point of visible area; And the collocation light-emitting component quantity (like odd number or even number) and adopt above-mentioned formula so that light-emitting component is disposed on the incidence surface; So can promote the overall brightness of the exiting surface of LGP, and then can make backlight module that the backlight of preferable brightness is provided.

For let above-mentioned purpose of the present invention, characteristic, and advantage can be more obviously understandable, below cooperate appended accompanying drawing, elaborate as follows:

Description of drawings

Fig. 1 is the schematic top plan view of known a kind of backlight module;

Fig. 2 A is the schematic top plan view of the backlight module of one embodiment of the invention;

Fig. 2 B is the cut-away view of the backlight module that illustrated along the line AA ' of Fig. 2 A;

Fig. 3 is the schematic top plan view of the backlight module of another embodiment of the present invention.

Wherein, Reference numeral

100,200,300: backlight module 110: light emitting diode

120,210: LGP 122,212: incidence surface

112,222: light emitting surface 114,224: optical axis

214: exiting surface 214a: visible area

216: groove 220: light-emitting component

230: optical diaphragm group 240: reflector plate

C1: center point P 1: horizontal direction

P2: vertical direction L1: center line

X: width Y: length

d _m: distance theta _m: angle

Embodiment

Fig. 2 A is the schematic top plan view of the backlight module of one embodiment of the invention, and Fig. 2 B is the cut-away view of the backlight module that illustrated along the line AA ' of Fig. 2 A.Explanation for ease, Fig. 2 A only illustrates the light-emitting component of backlight module and the relative position of LGP, does not illustrate to be positioned at LGP diaphragm up and down.Please be simultaneously with reference to figure 2A and Fig. 2 B, the backlight module 200 of present embodiment comprises a LGP 210 and a plurality of light-emitting component 220.LGP 210 has an incidence surface 212 and an exiting surface 214, and wherein exiting surface 214 has a visible area 214a.Light-emitting component 220 is arranged on the incidence surface 212 of LGP 210, and wherein each light-emitting component 220 has a light emitting surface 222 and an optical axis 224 vertical with light emitting surface 222, and these optical axises 224 roughly intersect at the central point C1 of visible area 214a.

In the present embodiment, come the light of self-emission device 220 to be suitable for being incident to the inside of LGP 210 from incidence surface 212, and in wherein repeatedly after the refraction again by exiting surface 214 outgoing.In addition, light-emitting component 220 for example is to adopt light emitting diode, and wherein the kind of light emitting diode can be that side is penetrated luminous or top light emitting, looks closely user's design and demand and decides.In addition, the light emitting surface 222 of the usually most vertical light-emitting element 220 of the multiple light rays that light-emitting component 220 is sent wherein is positioned at light emitting surface 222 central authorities and is the strongest position of light intensity, and often is called optical axis.Therefore, the optical axis 224 of present embodiment may be defined as the middle position of light emitting surface 222.

In the present embodiment, the incidence surface 212 of LGP 210 is provided with odd number light-emitting component 220, shown in Fig. 2 A.In detail, the incidence surface 212 of LGP 210 is provided with 2n+1 light-emitting component 220, and n is the integer greater than zero.In addition, visible area 214a in the horizontal direction P1 have a width X and have a length Y at vertical direction P2.In the present embodiment, has an angle theta between the vertical direction P2 of the optical axis 224 of each light-emitting component 220 and visible area 214a _m, angle theta wherein _mBe defined as:

${\mathrm{\θ}}_m={\tan }^{-1}\left|\left(\frac{(2m+\mathrm{\σ})X}{(2n+1)Y}\right)\right|,$

M is the integer of 0～n, and-1＜σ＜1.That need explain in addition, is θ ₀Representative is angle between the vertical direction P2 of light-emitting component 220 its optical axises in the middle of the ordering of a plurality of light-emitting components 220 and visible area 214a.

In addition, visible area 214a has a centre line L 1 on vertical direction P2, and has one apart from d between each light-emitting component 220 of along continuous straight runs P1 and the centre line L 1 _mFor, d wherein _mBe defined as:

$d_m=\left|(1+\frac{2a}{Y})(m+\mathrm{\σ})\frac{X}{2n+1}\right|$

M is the positive integer of 0～n ,-0.5＜σ＜0.5, and a is defined as the distance at the incidence surface 212 of LGP 210 to the edge of visible area 214a, and incidence surface 212 refers to the plane at parallel visible area 214a edge here.

Hold said structure; If width X is less than length Y; Then representing light-emitting component 220 is the minor face incident with LGP 210; And, so, can improve the refraction number of times of light in LGP 210 that light-emitting component 220 is provided because of light-emitting component 220 is to adopt above-mentioned condition setting on the incidence surface 212 of LGP 210.In the present embodiment; Under the situation of width X less than length Y; Light-emitting component 220 adopts above-mentioned configuration mode can promote the ray refraction number of times that is incident in LGP 210 inside, and can be promoted to 8.1% at least compared to the configuration mode that adopts known technology.

In addition; If width X is greater than length Y; Then representing light-emitting component 220 is the long limit incident with LGP 210, likewise, if light-emitting component 220 adopts above-mentioned condition setting when the incidence surface 212 of LGP 210; Then can promote the ray refraction number of times that is incident in LGP 210 inside, and can be promoted to more than 50.9% at least compared to the configuration mode that adopts known technology.

In other words; The light no matter light-emitting component 220 is provided is long limit or the minor face incident from LGP 210; As long as the optical axis 224 of each light-emitting component 220 roughly intersects at the central point C1 of visible area 214a; And each light-emitting component 220 can adopt above-mentioned condition setting when the incidence surface 212 of LGP 210, then can promote light in the inner refraction number of times of LGP 210, and then promotes the overall brightness of exiting surface 214.In addition, the optical axis 222 of each light-emitting component 220 of the present invention roughly intersects is provided with notion, also can effectively improve the problem of bright blanking bar around the visible area 214a of LGP 210, the difference that can reduce bright blanking bar with improve the light homogeneity.

In the present embodiment, have a plurality of grooves 216 on the incidence surface 212 of LGP 210, and be placed with a light-emitting component 220 in each groove 216, shown in Fig. 2 A.Wherein, these grooves 216 have an angle of inclination (indicate) respectively, and more little the closer to the angle of inclination of the groove 216 of the centre line L 1 of LGP 210.The size at this angle of inclination and above-mentioned angle theta _mCan be identical in fact.Groove 216 can be used as light-emitting component 220 assembling and positioning structures.

In addition, backlight module 200 more comprises an optical diaphragm group 230 and a reflector plate 240, shown in Fig. 2 B.In the present embodiment, optical diaphragm group 230 is arranged at the top of the exiting surface 214 of LGP 210, and reflector plate 240 is arranged on the surface of exiting surface 214 subtends of LGP 210.Optical diaphragm group 230 can be diffusion sheet, brightening piece, even sheet and combined optical sheet one of which at least.In addition, the LGP 210 of present embodiment is to be that example is explained with the wedge shape LGP, but the invention is not restricted to this kind LGP.

Fig. 3 is the schematic top plan view of the backlight module of another embodiment of the present invention.Likewise, explanation for ease, Fig. 3 only illustrates the light-emitting component of backlight module and the relative position of LGP, does not illustrate to be positioned at LGP diaphragm up and down.Please be simultaneously with reference to figure 2A and Fig. 3, the backlight module 300 of present embodiment is similar with backlight module 200, but the two difference is in, the slightly different backlight module 200 of the configuration mode of the light-emitting component 210 of backlight module 300, and it specifies as follows.

In backlight module 300, the incidence surface 212 of LGP 210 is provided with even number light-emitting component 220, and is as shown in Figure 3.In detail, the incidence surface 212 of LGP 210 is provided with 2n light-emitting component 220, and n is the positive integer greater than zero.In addition, visible area 214a in the horizontal direction P1 have a width X and have a length Y at vertical direction P2.In the present embodiment, has an angle theta between the vertical direction P2 of the optical axis 224 of each light-emitting component 220 and visible area 214a _m, the angle theta of present embodiment wherein _mBe defined as:

${\mathrm{\θ}}_m={\mathrm{Tan}}^{-1}\left|\left(\frac{((2m-1)+\mathrm{\σ})X}{2\mathrm{NY}}\right)\right|,$ And θ _m≠ 0

M is the positive integer of 1～n, and-0.5＜σ＜0.5.

Likewise, visible area 214a has a centre line L 1 on vertical direction P2, and has one apart from d between each light-emitting component 220 of along continuous straight runs P1 and the centre line L 1 _mFor, the d of present embodiment wherein _mBe defined as:

$d_m=\left|(1+\frac{2a}{Y})((2m-1)+\mathrm{\σ})\frac{X}{4n}\right|,$ And d _m≠ 0

And m is the positive integer of 1～n, and a is the distance at the incidence surface 212 of LGP 210 to the edge of visible area 214a, and incidence surface 212 refers to the plane at parallel visible area 214a edge here, and-1＜σ＜1.

Hold and above-mentionedly know, because of the quantity of the light-emitting component 220 of backlight module 300 is even number, therefore, the condition that light-emitting component 220 is arranged on the incidence surface 212 changes equally, for example angle theta _m, apart from d _mEtc. parameter.And, though angle theta _m, apart from d _mThe and then quantity of light-emitting component 220 and adjusting, however identical with above-mentioned backlight module 200 is that the optical axis 224 of each light-emitting component 220 is the central point C1 that roughly intersects at visible area 214a equally, and is as shown in Figure 3.

In other words, the backlight module 300 of present embodiment is different with the quantity that backlight module 200 is merely light-emitting component 220, and wherein light-emitting component 220 is arranged at parameter condition on the incidence surface 212 (like angle theta _m, apart from d _m) can adopt odd number or even number and slightly adjust along with the quantity of light-emitting component 220, therefore, the backlight module 300 of present embodiment has the mentioned advantage of backlight module 200 equally, repeats no more at this.

In sum, backlight module of the present invention has advantage at least.At first; The optical axis of each light-emitting component can roughly intersect at the central point of visible area; Thus; The light that light-emitting component provided can concentrate in the visible area, and then can promote the overall brightness of exiting surface, and the light that light-emitting component provided that is positioned at the LGP edge also is difficult for outside the dispersion light-guiding board.In addition, to the light-emitting component (like odd number or even number) of varying number, light-emitting component is arranged at parameter condition on the incidence surface (like angle theta _m, apart from d _m) also can and then adjust, be incident in the ray refraction number of times in the LGP with lifting, and then can further promote the overall brightness of backlight module.In addition, can improve the visible area picture because of the uneven bright blanking bar phenomenon that is caused of distribution of light sources.

Certainly; The present invention also can have other various embodiments; Under the situation that does not deviate from spirit of the present invention and essence thereof; Those of ordinary skill in the art work as can make various corresponding changes and distortion according to the present invention, but these corresponding changes and distortion all should belong to the protection domain of the appended claim of the present invention.

Claims (5)

1. a backlight module is characterized in that, comprising:

One LGP, it has an incidence surface and an exiting surface, and this incidence surface is in abutting connection with this exiting surface, and wherein this exiting surface has a visible area; And

A plurality of light-emitting components are arranged on this incidence surface of this LGP, and wherein each light-emitting component has a light emitting surface and an optical axis vertical with this light emitting surface, and said optical axis roughly intersects at the central point of this visible area; Wherein

This incidence surface of this LGP is provided with the even number light-emitting component;

This visible area has a width X in the horizontal direction and has a length Y in vertical direction, has an angle theta between the optical axis of each light-emitting component and the vertical direction of this visible area _mFor:

${\mathrm{\θ}}_m={\mathrm{Tan}}^{-1}\left|\left(\frac{((2m-1)+\mathrm{\σ})X}{2\mathrm{NY}}\right)\right|,$ And θ _m≠ 0

Wherein, this incidence surface of this LGP is provided with 2n light-emitting component, and n ≠ 0, and m is the positive integer of 1～n, and-1＜σ＜1.

2. backlight module according to claim 1; It is characterized in that; This visible area has a width X in the horizontal direction and has a length Y in vertical direction, and this visible area has a center line in vertical direction, and has one apart from d between each light-emitting component of along continuous straight runs and this center line _mFor:

$d_m=\left|(1+\frac{2a}{Y})((2m-1)+\mathrm{\σ})\frac{X}{4n}\right|,$ And d _m≠ 0

Wherein, this incidence surface of this LGP is provided with 2n light-emitting component, n ≠ 0, and m is the positive integer of 1～n, a is the distance at edge of this incidence surface to this visible area of this LGP, and-1＜σ＜1.

3. backlight module according to claim 1 is characterized in that, has a plurality of grooves on this incidence surface of this LGP, and is placed with a light-emitting component in each groove.

4. backlight module according to claim 3 is characterized in that this visible area has a center line in vertical direction, and said groove has an angle of inclination respectively, and more little the closer to the angle of inclination of the groove of this center line of this LGP.

5. backlight module according to claim 1 is characterized in that, this backlight module more comprises:

One optical diaphragm group is arranged at the top of this exiting surface of this LGP; And

One reflector plate is arranged on the surface of this exiting surface subtend of this LGP.

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