TWI514053B - Backlight Module - Google Patents

Description

Backlight module

The invention relates to a backlight module, in particular to a backlight module for improving the phenomenon of jetting bright lines.

The liquid crystal display device includes a liquid crystal display panel (LCD panel) and a backlight module, wherein the backlight module is disposed under the liquid crystal display panel and is configured to provide a surface light source to the liquid crystal display panel. Therefore, the quality of the surface light source provided by the backlight module is closely related to the display quality of the liquid crystal display device. Referring to FIG. 1 , a conventional backlight module includes a back plate 90 , a light guide plate 91 , and a light source 92 . The light guide plate 91 is disposed on the back plate 90 , and the light guide plate 91 has a light incident surface 911 and a light exit surface 912 . The light emitted from the light source 92 is incident on the light incident surface 911 and is emitted to the liquid crystal display panel via the light exit surface 912.

In order to fix the light guide plate 91, a positioning hole 913 is disposed adjacent to the boundary of the light guide plate 91, and the positioning post 901 of the back plate 90 is disposed to fix the light guide plate 91, so that the light guide plate 91 does not easily occur. Shake the offset and even cause damage to the light guide. However, when the light source 92 reflects light to the positioning hole 913 of the light guide plate 91, it will generate a phenomenon of spraying a bright line (Mura) at the positioning hole 913, causing the display image of the visible area of the liquid crystal display panel to be blurred, especially narrow. The display of the frame design is particularly noticeable.

At present, the solution is to attach a light-absorbing black tape to the positioning hole 913 to reduce the phenomenon of spraying the bright line. However, after using this method for a period of time, the positioning post will be shaken due to the movement of the liquid crystal display device, causing the black tape to be damaged due to the shaking of the positioning post, resulting in a decrease in display taste.

In view of the above problems, the present invention provides a backlight module that can eliminate the phenomenon of total reflection of light rays in a part of the backlight module, and can avoid recurrence of the sprayed bright line (Mura) due to the shaking of the fixed column. Reduce maintenance costs.

The invention provides a backlight module, comprising: a light guide plate and an optical tape. The light guide plate has a through groove, a side surface, and opposite first and second surfaces. The side surface is connected between the first surface and the second surface, the through groove is located at a side of the light guide plate, and the first surface, the second surface and the third surface are respectively formed on the first surface, the second surface and the side surface. The optical tape has a continuous portion and two wings, wherein the continuous portion is attached to the second surface and exposes the third opening, and the two wings extend from the two ends of the continuous portion and around the edge of the third opening contour, and are extended The second opening and the edge of the first opening are attached to the side surface and the first surface and do not shield the first opening and the second opening, and the two wings are located on the first surface on both sides of the first opening.

According to the above structure, the optical tape is attached to the first surface, the second surface, and the side surface of the light guide plate, and surrounds the periphery of the first opening, the second opening, and the third opening, in other words, the optical tape is attached to the guide. The periphery of the light plate through the groove. Therefore, when the fixing post of the display is placed in the through slot, since the optical tape is only located at the periphery of the through slot, the fixing post has no contact with the optical tape, and therefore the fixing post does not move due to shaking when the display moves. The optical tape is damaged. In this way, since the optical tape is not damaged by the shaking of the fixing column, the optical tape located at the periphery of the through-groove can maintain the effect of disturbing the light reflection, thereby preventing the light from being emitted by the bright line. Reduce maintenance costs.

10‧‧‧Light guide plate

11‧‧‧through slots

12‧‧‧Central District

13‧‧‧ Peripheral area

14‧‧‧ baseline

101‧‧‧ first surface

102‧‧‧ second surface

103‧‧‧ side surface

104‧‧‧Stained surface

111‧‧‧ first opening

112‧‧‧ second opening

113‧‧‧ third opening

20‧‧‧Optical tape

21‧‧‧Continuous Department

22‧‧‧ wing

23‧‧‧Protruding

221‧‧‧ first fold line

222‧‧‧ second fold line

30‧‧‧Light source

40‧‧‧ Backboard

41‧‧‧Setting surface

42‧‧‧Positioning column

50‧‧‧reflector

90‧‧‧ Backplane

901‧‧‧Positioning column

91‧‧‧Light guide plate

92‧‧‧Light source

911‧‧‧Glossy

912‧‧‧Glossy

913‧‧‧Positioning holes

[Fig. 1] is a perspective exploded view of a backlight module of the prior art.

[Fig. 2] Fig. 2 is a perspective exploded view showing an embodiment of a backlight module of the present invention.

[Fig. 3] is a perspective plan view showing one of the light guide plate and the optical tape of the present invention.

Fig. 4 is a plan view showing one of the light guide plate and the optical tape of the present invention.

[Fig. 5] Fig. 5 is a perspective bottom view of one of the light guide plate and the optical tape of the present invention.

[Fig. 6] is a bottom view of one of the light guide plate and the optical tape of the present invention.

[Fig. 7] is a schematic view showing one of optical tapes of the backlight module of the present invention.

[Fig. 8] A schematic view showing the use of another embodiment of the reflection sheet of the present invention.

[Fig. 9] is a perspective exploded view of another embodiment of the backlight module of the present invention.

FIG. 2 is an exploded view of an embodiment of a backlight module of the present invention. As shown in FIG. 2 , the backlight module includes a light guide plate 10 , an optical tape 20 , a light source 30 , and a back plate 40 . The optical tape 20 is disposed on the surface of the light guide plate 10 , and the light source 30 is located on the side of the light guide plate 10 . The 40 series houses the light guide plate 10.

Fig. 3 is a perspective plan view showing one of the light guide plate 10 and the optical tape 20 of the present invention. Fig. 4 is a plan view showing one of the light guide plate 10 and the optical tape 20 of the present invention. Figure 5 is the current issue A perspective view of one of the light guide plate 10 and the optical tape 20 of the present invention. Fig. 6 is a bottom plan view of the light guide plate 10 and the optical tape 20 of the present invention. In the third to sixth figures, only the light source 30 and the back plate 40 of the backlight module are omitted.

Referring to FIGS. 2-6, the light guide plate 10 has a through slot 11, a side surface 103, and opposite first and second surfaces 101, 102, wherein the side surface 103 is coupled to the first surface 101 and the second surface 102. between. The through slot 11 is located at one side of the light guide plate 10, and forms a first opening 111, a second opening 112 and a third opening 113 on the first surface 101, the second surface 102 and the side surface 103, respectively; that is, the light guide plate The first opening 111 and the second opening 112 are respectively formed on the two ends of the through hole 11 , and the two ends of the third opening 113 respectively adjoin the first opening 111 and the second opening 112 , and An opening 111 is located on the first surface 101, a second opening 112 is located on the second surface 102, and a third opening 113 is located on the side surface 103. The aperture of the through slot 11 is between 3 mm and 4 mm. In the embodiment, the aperture of the through slot 11 is preferably 3.6 mm, but the invention is not limited thereto.

4, the light guide plate 10 includes a central region 12 and a peripheral region 13 surrounding the periphery of the central region 12. The through-groove 11 is located in the peripheral region 13 , and the contour edges of the first opening 111 and the second opening 112 do not exceed the central region 12 ; that is, the contour of the first opening 111 on the first surface 101 is only located in the peripheral region 13 . The boundary between the central portion 12 and the peripheral portion 13 is not touched, and the contour of the second opening 112 on the second surface 102 is correspondingly located in the peripheral region 13, and the second opening 112 does not correspondingly touch the center. The boundary between the zone 12 and the peripheral zone 13. Therefore, the contour edge of the through slot 11 is only located in the peripheral edge region 13 and does not contact the boundary between the central region 12 and the peripheral edge region 13, and the contours of the first opening 111 and the second opening 112 of the through slot 11 are located in the peripheral edge region 13 Inside.

Referring to FIG. 2 again, the backing plate 40 includes a setting surface 41 and a positioning post 42. The positioning post 42 is located in the setting surface 41 and is disposed in the through slot 11 when the light guide plate 10 is placed on the backing plate 40. When the surface 41 is above, the positioning post 42 is penetrated by the second opening 112 of the through slot 11 and passes through the first opening 111, and the side wall of the positioning post 42 abuts against the first opening 111 and the second opening 112. Connected connection surface. As a result, the light guide plate 10 is fixed to the positioning post 42 of the back plate 40 by the through slot 11 , and the positioning post 42 is located only in the peripheral edge region 13 of the light guide plate 10 corresponding to the through slot 11 , thereby avoiding the light guide plate 10 . The displacement and the through-groove 11 can avoid affecting the effect of the light guide plate 10 guiding the light in the central region 12, that is, avoiding the display taste degradation.

Furthermore, the light source 30 is disposed on the light receiving surface 104 of the light guide plate 10 (as shown in FIG. 2), the light receiving surface 104 is adjacent to the side surface 103, and when the light source 30 emits light, the first surface 101 is a light emitting surface; That is, the light source 30 is disposed adjacent to the light receiving surface 104, and the light emitted from the light source 30 is incident on the light receiving surface 104, and is reflected by the inside of the light guide plate 10, and then the first surface 101 serves as a light emitting surface to uniformly emit light. The corresponding liquid crystal display panel can be displayed for viewing. In addition, in the embodiment, the light source 30 is a plurality of LEDs, and the invention is not limited thereto.

Moreover, the light guide plate 10 has a strip-like microstructure (not shown) on the first surface 101, and the strip-shaped microstructure is perpendicular to the light-receiving surface 104, and the light source 30 emits light into the light-receiving surface 104, thereby utilizing the strip-shaped microstructure. Light is supplied to the light guide plate 10 to be reflected more concentrated in the normal direction of the light exit surface (first surface 101), thereby increasing the luminance.

Figure 7 is a schematic view of the optical tape 20 of the backlight module of the present invention. Referring to FIG. 7, the optical tape 20 has a continuous portion 21 and two wings 22. The continuous portion 21 is attached to the second surface 102 (as shown in Figures 5-6) and exposes the third opening 113. Two wings 22 are from Two ends of the continuous portion 21 attached to the second surface 102 extend around the contour edge of the third opening 113, and then continue to extend and adhere to the second opening 112 at the side surface 103 and the first opening 111 at the first surface 101 The two sides of the edge do not cover the second opening 112 and the first opening 111 (as shown in FIGS. 3-6); that is, the optical tape 20 is attached to the periphery of the through slot 11 of the light guide plate 10, and The second surface 102 of the light guide plate 10 is attached to the first surface 101 and includes the attachment side surface 103, that is, the optical tape 20 only surrounds the contour circumference or both sides of the through groove 11 to avoid the through groove 11 so as to penetrate through There is no optical tape 20 in the middle of the groove 11.

Furthermore, as shown in FIGS. 5-6, the optical tape 20 further includes a protruding portion 23 formed on both sides of the optical tape 20 and correspondingly attached to the second surface 102; in other words, the protruding portion 23 is formed on the wing The portion 22 is opposite to the other side of the continuous portion 21 and correspondingly attached to the second surface 102, thereby enhancing the interference effect of the light on the first surface 101 at the periphery of the through slot 11 , that is, when the light source 30 When the light is reflected to the through-groove 11 of the light guide plate 10, a phenomenon of spraying a bright line (Mura) is generated at the through-groove 11, and the periphery of the through-hole 11 interferes with light reflection by attaching the optical tape 20, and the optical tape 20 is attached. When the second surface 102 is extended, the interference range is extended by the protruding portion 23, because the protruding portion 23 prematurely destroys the light reflecting path, so that the light refracting of the first surface 101 adjacent to the through groove 11 is more severely damaged, thereby serving as a light emitting surface. The first surface 101 is produced to reduce the phenomenon of jetting bright lines.

In the present embodiment, the optical tape 20 has a first fold line 221 and a second fold line 222 (shown in FIG. 7), which are respectively located on the wings 22, and the first fold lines 221 are respectively located on the first surface 101 and The second surface line 222 is respectively located at the junction of the second surface 102 and the side surface 103, that is, the first fold line 221 is adjacent to the wing 22 From the end, the second fold line 222 is adjacent to the connecting portion 21. This makes it easy to install the adhesive and saves assembly man-hours.

Referring again to FIG. 4, the light guide plate 10 has a reference line 14, and the reference line 14 passes through the protruding point of the first opening 111 closest to the central portion 12, and the two wings 22 of the optical tape 20 are attached to the first portion. The extent of a surface 101 does not exceed the reference line 14; in other words, the reference line 14 is cut away from the protruding point of the contour of the first opening 111, and the reference line 14 is located in the peripheral region 13, so that the respective wings 22 of the optical tape 20 correspond to The free end of the first surface 101 does not exceed the reference line 14, that is, the free end of each wing portion 22 is between the intersection of the first surface 101 and the side surface 103 and the reference line 14; in this embodiment, The intersection of the first surface 101 and the side surface 103 is parallel to the reference line 14, and the invention is not limited thereto. Furthermore, in the present embodiment, the shortest distance from the point of protrusion to the boundary of the central zone 12 is between 0.5 mm and 3 mm.

Furthermore, in the present embodiment, if the optical tape 20 is not disposed on the light guide plate 10, the length of the jet bright line at the through groove 11 of the light guide plate 10 is about 2-3 mm, so when the optical tape 20 is set In the case of the light guide plate 10, and the area of the optical tape 20 on the second surface 102 is larger than the area attached to the first surface 101, when the light is guided in the light guide plate 10, the area of the optical tape 20 on the second surface 102 is Larger, such that when light is directed to the second surface 102, the total reflection of the light is prematurely destroyed, plus a thickness distance between the second surface 102 and the first surface 101, causing the ejection at the first surface 101. The phenomenon of bright lines is further reduced; in other words, because the area of the optical tape 20 attached to the second surface 102 is large, the light is prematurely destroyed by the total reflection on the second surface 102, so that the ejection of the first surface 101 is bright. The phenomenon of the line will decrease. Moreover, the optical tape 20 extends over the second surface 102 to extend to the region of the light guide plate 10 corresponding to the central region 12, and the present invention is not limited thereto.

In addition, in the present embodiment, each wing portion 22 of the optical tape 20 corresponds to the length of the second surface, and the length of each wing portion 22 corresponding to the boundary between the reference line 14 and the first surface 101 and the side surface 103 is between Between 0 mm and 2 mm, the present invention is not limited thereto, and the length range can be designed according to the range of the bright line of the aperture of the through-groove 11 of the light guide plate 10.

Furthermore, in the present embodiment, the length of the boundary between the central region 12 and the peripheral region 13 of the light guide plate 10 to the reference line 14 is between 1 mm and 4 mm, but the present invention is not limited thereto. The range of the bright line of the aperture of the light plate 10 through the slot 11 is designed to be this length range.

Moreover, in the embodiment, the width of the optical tape 20 attached to the second surface 102 and the width of the first surface 101 are between 0.5 mm and 20 mm, but the invention is not limited thereto. The length range can be designed according to the range of the bright line of the aperture of the through-groove 11 of the light guide plate 10; wherein the direction of the width of the optical tape 20 is the direction of the linear distance between the two protrusions 23, that is, as shown in FIG. The left and right horizontal directions shown.

Referring to FIG. 2 again, the backlight module includes a reflective sheet 50 disposed on the side surface 103 adjacent to one of the two wings 22, and the reflectance of the reflective sheet 50 is preferably less than or equal to optical. The reflectivity of the tape 20; that is, the reflective sheet 50 is disposed on the side surface 103 adjacent to one of the wings 22, and the reflectance via the reflective sheet 50 is not equal to the optical tape 20, whereby the light can be reflected and guided to The first surface 101 of the light-emitting surface emits light, thereby obtaining a distribution of luminance, chromaticity and central region 12 of the region to prevent the light from being emitted into the bright line. The reflectance of the reflective sheet 50 is less than or equal to the reflectivity of the optical tape 20, and the purpose thereof is to prevent the brightness of the bright line range of the optical tape 20 from being too bright. In addition, in the embodiment, the reflective sheet 50 and the optical tape 20 have a gap therebetween. The distance is between 0 mm and 2 mm, but the invention is not limited thereto. The length of the reflective sheet 50 in this embodiment is greater than 20 mm, but the invention is not limited thereto.

In addition, the reflective sheet 50 preferably has a color selected to be gray, and its reflectance is smaller than that of white, mainly because the white reflective sheet 50 causes strong total reflection damage, that is, the light is reflected at a short distance. Further, a bright bright band is generated, that is, if the reflection sheet 50 is white, the brightness in the range of the bright line of the light emission is higher than the brightness of the reflection sheet 50 using the gray.

Furthermore, the material of the reflective sheet 50 is selected from a non-metallic material, mainly because the metal material strongly reflects the light from the side surface 103 toward the central portion 12 of the light guide plate 10, resulting in the brightness of the visible region of the central region 12. Not uniform.

Fig. 8 is a schematic view showing the use of another embodiment of the reflection sheet 50 of the present invention. Referring to FIG. 8, the reflective sheet 50 may also be disposed on the opposite side wings 22 of the optical tape 20, and attached to the side surface 103, respectively, thereby reflecting and guiding the light to the light. The first surface 101 of the surface emits light, and the distribution of the luminance, the chromaticity and the central region of the region is obtained, thereby preventing the light from being emitted into the bright line.

The backlight module formed by the above structure is attached to the first surface 101, the second surface 102, and the side surface 103 of the light guide plate 10 through the optical tape 20, and the optical tape 20 surrounds the first opening 111 and the second surface, respectively. The edge of the opening 112 and the third opening 113, whereby the optical tape 20 is not located within the through slot 11, that is, the optical tape 20 is not located between the first opening 111, the second opening 112 and the third opening 113; In this way, the sway of the positioning post 42 can be avoided to damage the optical tape 20, and the optical tape 20 can maintain the interference light reflection, thereby preventing the light from being sprayed with the bright line, thereby reducing the maintenance cost.

FIG. 9 is a perspective exploded view of another embodiment of the backlight module of the present invention. As shown in FIG. 9 , the light guide plate 10 further includes two through slots 11 , and the optical tape 20 has a corresponding number of two continuous portions 21 and three wings 22 , thereby accommodating the corresponding two positioning posts 50 , that is, The light guide plate 10 of the present invention can increase the through-groove 11 correspondingly, and the optical tape 20 correspondingly increases the continuous portion 21 and the wing portion 22, thereby accommodating a corresponding number of positioning posts 42, which are not limited thereto. In this way, the optical tape 20 is attached to the periphery of the through-groove 11 of the light guide plate 10, thereby preventing the optical column 20 from being damaged by the shaking of the positioning post 42, and the optical tape can maintain the interference light reflection, thereby preventing the light from being sprayed. The phenomenon can also reduce maintenance costs.

10‧‧‧Light guide plate

11‧‧‧through slots

101‧‧‧ first surface

102‧‧‧ second surface

103‧‧‧ side surface

104‧‧‧Stained surface

111‧‧‧ first opening

112‧‧‧ second opening

113‧‧‧ third opening

20‧‧‧Optical tape

22‧‧‧ wing

23‧‧‧Protruding

30‧‧‧Light source

40‧‧‧ Backboard

41‧‧‧Setting surface

42‧‧‧Positioning column

50‧‧‧reflector

Claims (12)

A backlight module includes: a light guide plate having a through groove, a side surface, and a first surface and a second surface, wherein the side surface is connected between the first surface and the second surface, The through slot is located at a side of the light guide plate, and forms a first opening, a second opening and a third opening respectively on the first surface, the second surface and the side surface; and an optical tape having a continuous portion and two wings, wherein the continuous portion is attached to the second surface and exposes the third opening, and the two wings are from the two ends of the continuous portion and around the edge of the third opening contour Extending along the edge of the second opening and the first opening to the side surface and the first surface without shielding the first opening and the second opening, and the two wings are on the first surface It is located on two sides of the first opening. The backlight module of claim 1, wherein the backlight module comprises a reflective sheet disposed on the side surface adjacent to one of the two wings. The backlight module of claim 2, wherein a reflectance of the reflective sheet is less than or equal to a reflectivity of the optical tape. The backlight module of claim 2, wherein each of the reflective sheet and the optical tape has a gap between 0 mm and 2 mm. The backlight module of claim 1, wherein the light guide plate comprises a central area and a peripheral area surrounding the central area, wherein the through groove is disposed in the peripheral area, and the first opening and the second opening The contour edge does not exceed the central zone. The backlight module of claim 5, further comprising a reference line, wherein the contour of the first opening is closest to a protruding point of the central area, and the range of the two wings attached to the first surface does not exceed The baseline. The backlight module of claim 6, wherein the shortest distance from the protruding point to the central area is between 0.5 mm and 3 mm. The backlight module of claim 1, wherein the backlight module further comprises a light source, the light source is disposed on a light receiving surface of the light guide plate, the light receiving surface is adjacent to the side surface, and when the light source emits a light, the light source The first surface is a light exit surface. The backlight module of claim 1, wherein the optical tape is attached to the second surface with an area larger than an area attached to the first surface. The backlight module of claim 1, wherein the backlight module has a positioning post, and the positioning post is received in the through slot. The backlight module of claim 1, wherein the optical tape has a first fold line and a second fold line, wherein the first fold line is respectively located at a joint between the first surface and the side surface, and the second fold line respectively corresponds to Located at a junction of the second surface and the side surface. The backlight module of claim 1, wherein the optical tape further comprises two protrusions respectively attached to the second surface, the protrusions being respectively formed on each of the wings and opposite to the other side of the continuous portion .