TWI546596B - Light guide plate and lighting mogule - Google Patents

Description

Light source module and light guide plate

The invention relates to a light source module and a light guide plate, and particularly relates to a side-entry light source module and a light guide plate applied to the side-entry light source module.

The backlight module is an important component of the liquid crystal display, and the side-in backlight module is mounted on the side of the light guide plate, as shown in FIG. 1 , by forming an optical pattern with light-receiving capability on the light guide plate. It can provide a surface light source with sufficient brightness and uniform intensity distribution.

In FIG. 1 , the side-entry light source module includes a light guide plate 300 and a light bar 400 . The light guide plate 300 includes a light incident side surface 310, a visible area 320, and a transition area 330. The viewing area 320 is provided with an optical pattern (not shown) that is light-increasing from the light-incident side 310 toward the side that is away from the light-incident side. The transition zone 330 is between the light incident side 310 and the viewable area 320. In general, when the liquid crystal display is assembled, the transition zone 330 is covered with an opaque frame to shield the dark areas of the vision that are limited by the light exit angle of the light source.

The light bar 400 includes a first light emitting element 410 and an second light emitting element 420. The first light emitting element 410 is located at an end of the light bar 400, and the second light emitting element 420 is adjacent to the first light emitting element 410. Different from the second illumination source member 420.

When the second light-emitting element 420 emits light, the light-emitting panel 300 is formed with a corner dark area 500 that the light-emitting angle of the second light-emitting element 420 (shown by a broken line in FIG. 1 ) cannot be covered; if the corner dark area 500 penetrates the visible area 320, The visible area 320 may cause a problem of uneven intensity distribution, thereby affecting the display effect of the liquid crystal display having the side-in type light source module.

The invention provides a light source module for avoiding forming a dark area in a corner of a visible area of the light guide plate, thereby providing a surface light source with uniform intensity distribution.

According to the present invention, a light source module includes a light bar and a light guide plate. The light bar has a first light emitting element and a second light emitting element. The first light emitting element is located at one end of the light bar, the second light emitting element is adjacent to the first light emitting element, and the starting time of the first light emitting element is different from the second light emitting element. The light guide plate comprises a light incident side, a visible area, a transition area, a first corner optical microstructure pattern and a second angle optical microstructure pattern. The light entrance side faces the light bar to receive light incident. The viewable area has an optical pattern, and the light taking capability of the optical pattern linearly increases from the adjacent light incident side toward the light entrance side. The transition zone is between the incoming side and the visible section. The first corner optical microstructure pattern is located in the visible area in front of the first light-emitting element, and is used to remove relatively weak light at a relatively high density when the second light-emitting element is activated to avoid forming a dark corner on the visible area. Area. The second corner optical microstructure pattern is located in a transition area in front of the first corner optical microstructure pattern, and is used to remove relatively strong light at a relatively high density when the first light emitting element is activated, thereby avoiding relatively strong The light contacts the first corner optical microstructure pattern and forms a corner bright area on the visible area.

The first corner optical microstructure starts from the first interface adjacent to the visible area and the transition area, and finally the second interface, the second corner optical microstructure starts from the light incident side, finally the first interface, between the light entrance side and the first interface The distance is d1, the distance between the first interface and the second interface is d2, the first light exit angle of the first light-emitting element is 2A, and the second light exit angle of the second light-emitting element is 2B, the first light-emitting element and the first light-emitting element The distance between the two light-emitting elements is 2 h, which satisfies the following conditions: tanA=h/d2; and tanB=2h/(d1+d2).

When the first corner optical microstructure pattern and the second corner optical microstructure pattern are actually disposed, the projection length of the first corner optical microstructure pattern on the light incident side is away from the light incident side. Gradually, the projection length of the second corner optical microstructure pattern on the light incident side gradually decreases with the direction away from the light incident side.

The invention further provides another light guide plate, which is formed with a corner optical microstructure pattern with a high light extraction capability, and a corner of the light source module formed by the point source with the asynchronous control. Dark area problem.

According to the present invention, there is further provided a light guide plate comprising a light incident side surface, a visible area, a transition area, a first corner optical microstructure pattern and a second corner optical microstructure pattern. The viewable area has an optical pattern, and the light taking capability of the optical pattern linearly increases from the adjacent light incident side toward the light entrance side. The transition zone is between the incoming side and the visible section. The first corner optical microstructure pattern is located in one of the transition zones adjacent to the viewing zone. The second corner optical microstructure pattern is located in a transition zone in front of the first corner optical microstructure pattern.

When the first corner optical microstructure pattern and the second corner optical microstructure pattern are actually disposed, the projection length of the first corner optical microstructure pattern on the light incident side surface gradually decreases with a direction away from the light incident side surface, and the second corner optical micro The projected length of the structural pattern on the light incident side gradually decreases as it goes away from the light incident side.

The invention can effectively avoid the occurrence of corner dark areas and corner bright areas of the light source module through the arrangement of the first corner optical microstructure pattern and the second corner optical microstructure pattern.

100, 400‧‧‧ light bars

110, 410‧‧‧ first light-emitting elements

120, 420‧‧‧second light-emitting elements

130‧‧‧ Carrier Board

200, 300‧‧‧ light guide plate

210, 310‧‧‧ light side

220, 320‧‧‧ visual area

222‧‧‧ optical pattern

230, 330‧‧‧ transition zone

240‧‧‧First corner optical microstructure pattern

250‧‧‧second corner optical microstructure pattern

260‧‧‧ first interface

270‧‧‧second interface

1 is a schematic diagram of light distribution of a conventional side-entry light source module; FIG. 2 is a schematic diagram of light distribution of a light source module of the present invention; and FIG. 3 is a partial enlarged view of the light source module of the present invention.

Referring to FIG. 2 and FIG. 3 , the light source module includes a light bar 100 and a light guide plate 200 . The light bar 100 includes a first light emitting element 110 and an second light emitting element 120. The first light emitting element 110 is located at an end of the light bar 100, and the second light emitting element 120 is adjacent to the first light emitting element 110.

The starting timing of the first illuminating element 110 is different from the starting timing of the second illuminating element 120, and the first illuminating element 110 and the second illuminating element 120 are alternately turned off; wherein the starting of the first illuminating element 110 and the second illuminating element 120 The timing is when the first light-emitting element 110 and the second light-emitting element 120 are illuminated to emit light, and the following when the light-emitting element is activated means that the light-emitting element is turned on. The first light emitting element 110 and the second light emitting element 120 can be realized by the light emitting diodes, respectively. The first light-emitting element 110 has a first light-emitting angle 2A, and the second light-emitting element 120 has a second light-emitting angle 2B. The first light-emitting angle 2A and the second light-emitting angle 2B are respectively used by the first light-emitting element 110 and the second light-emitting element 120. The 50% light intensity envelope is defined.

The light bar 100 may further include a carrier 130. The first light emitting element 110 and the second light emitting element 120 are respectively disposed on the carrier 130, and can receive power required for starting the timing through the carrier 130.

The light guide plate 200 has a flat shape and is transparent to light, and is usually composed of acrylic (PMMA) or plastic (PC), but does not exclude other equals; for example, the light guide plate 200 may be acrylic resin (Acrylic Resin), cycloolefin A group of materials composed of polymer (COC), polymethyl methacrylate (PMMA), polycarbonate (PC), polyetherimide, fluorocarbon polymer or silicone (Silicone) At least one of the materials or other alternative materials.

The light guide plate 200 includes a light incident side surface 210, a visible region 220, and a transition region 230. The light incident side surface 210 faces the light bar 100 to receive light incident. As shown in FIG. 2, the light guide plate and the light bar 100 cooperate to form a side-entry light source module. The visible area 220 is an area of uniform intensity, so it can be directly overlapped with the effective display area of the liquid crystal display panel to provide a surface light source when the liquid crystal display panel is operated. The transition region 230 is between the light incident side surface 210 and the visible light region 220. The transition region 230 is adjacent to the first light emitting element 110 and the second light emitting element 120, and is limited by the light emitting angles of the first light emitting element 110 and the second light emitting element 120. Will form a bright contrast zone And dark areas. Since the bright regions and the dark regions distributed in the transition region 230 cannot be remedied by the density change of the optical pattern, the light-shielding material is generally covered on the transition region 230 to avoid affecting the light-emitting effect.

The light guide plate 200 further includes a first corner optical microstructure pattern 240 and a second corner optical microstructure pattern 250. The first corner optical microstructure pattern 240 is located in the visible region 220 in front of the first light emitting element 110, and is more precisely designed. The first corner optical microstructure pattern 240 is located in the visible region 220 adjacent to the transition region 230. The second corner optical microstructure pattern 250 is located within the transition region 230 in front of the first corner optical microstructure pattern 240.

The viewing area 220 further has an optical pattern 222. The light extraction capability of the optical pattern 222 is linearly increased from the light incident side 210 toward the light incident side surface 210 for uniformizing the light generated by the first light emitting element 110 and the second light emitting element 120. The light guide plate 200 is guided to the rear end side of the light incident side surface 210. The light extraction capability can be adjusted by adjusting the density, size, or a combination of the optical patterns 222.

The outlines of the first corner optical microstructure pattern 240 and the second corner optical microstructure pattern 250 may be defined by the second light exit angle 2B of the second light emitting element 120, and more specifically, the first corner optical microstructure pattern 240 and The second corner optical microstructure pattern 250 is not in the range covered by the second light exit angle 2B.

In FIG. 2, the first corner optical microstructure pattern 240 starts from the first interface 260 adjacent to the transition region 230 of the visible region 220, and the projected length of the first corner optical microstructure pattern 240 on the light incident side surface 210 is further away. The light side 210 is shortened and finally the second interface 270. The second corner optical microstructure pattern 250 begins at the light incident side surface 210, finally the first interface 260, and the projected length of the second corner optical microstructure pattern 250 on the light incident side surface 210 is shortened as it moves away from the light incident side surface 210.

As shown in FIG. 3, the light-emitting angle of the first light-emitting element 110 is 2A, the light-emitting angle of the second light-emitting element 120 is 2B, the distance between the light-incident side surface 210 and the first interface 260 is d1, and the first interface 260 and the second interface The distance between the interfaces 270 is d2, which satisfies the following conditions: tanA=h/d2; and tanB=2h/(d1+d2).

The outlines of the first corner optical microstructure pattern 240 and the second corner optical microstructure pattern 250 may be defined by the second light exit angle 2B of the second light emitting element 120, and more specifically, the first corner optical microstructure pattern 240 and The second corner optical microstructure pattern 250 is not in the range covered by the second light exit angle 2B.

The density of the optical pattern formed between the first interface 260 and the second interface 270 is less than the density of the first corner optical microstructure pattern 240. Thereby, the first corner optical microstructure pattern 240 can take out the relatively weak light at a relatively high density when the second light emitting element 120 is activated, thereby avoiding forming a corner dark area on the visible area 220.

Although the first corner optical microstructure pattern 240 can effectively prevent the generation of the dark area of the corner when the second light emitting element 120 is activated, when the first light emitting element 110 is activated, the light is also taken out at a relatively high density. Lead to the emergence of corner highlights. In order to avoid the occurrence of corner highlights, the density of the second corner optical microstructure pattern 250 must be made higher than the density of the first corner optical microstructure pattern 240. Thereby, the second corner optical microstructure 250 can take out relatively strong light at a relatively high density when the first light emitting element 110 is activated, so as to prevent relatively strong light from contacting the first corner optical microstructure pattern 240. While the visible area 220 forms a corner bright area, the visible area 220 can provide a uniform intensity light source.

Although the light extracted by the second corner optical microstructure pattern 250 when the first light emitting element 110 is activated may generate a local bright spot in the transition region 230; in general, the transition region 230 of the light guide plate 200 covers the opaque material. The phenomenon that the intensity formed in the transition region 230 is limited by the light-emitting angle and the arrangement distance of the light-emitting elements is uneven. Therefore, the local bright spots formed in the transition region 230 can be simultaneously shielded by the opaque material without affecting the intensity uniformity of the light source module when actually applied to the liquid crystal display.

While the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and the invention may be modified and modified in various ways without departing from the spirit and scope of the invention. The scope is subject to the definition of the scope of the patent application.

100‧‧‧Light strips

110‧‧‧First light-emitting element

120‧‧‧Second light-emitting element

130‧‧‧ Carrier Board

200‧‧‧Light guide plate

210‧‧‧light side

220‧‧‧visible area

222‧‧‧ optical pattern

230‧‧‧Transition zone

240‧‧‧First corner optical microstructure pattern

250‧‧‧second corner optical microstructure

Claims (7)

A light source module includes: a light bar having a first light emitting element at one end of the light bar and a second light emitting element adjacent to the first light emitting element, the first light emitting element and the second light emitting element And a light guide plate comprising: a light incident side facing the light strip to receive light incident; a visible area having an optical pattern, the optical pattern having a light extraction capability from the adjacent light incident side away from the light The direction of the light incident side is linearly increased; a transition region is between the light incident side and the visible interval; a first corner optical microstructure pattern is located in the visible region in front of the first light emitting element for the first When the two light-emitting elements are lit, the relatively weak light is taken out at a relatively high density to avoid forming a corner dark area on the visible area; and a second corner optical microstructure pattern is located in front of the first light-emitting element The transition region is configured to remove relatively strong light at a relatively high density when the first light-emitting element is illuminated, to avoid relatively strong light from contacting the first corner optical microstructure To form a bright area on the corner of the viewable area. The light source module of claim 1, wherein the first corner optical microstructure starts from a first interface adjacent to the visible region and the transition region, and finally a second interface, the second corner optical micro The structure starts from the light incident side, and finally the first interface, the distance between the light incident side surface and the first interface surface is d1, and the distance between the first interface surface and the second interface surface is d2, the first light emitting element A first light exit angle is 2A, and a second light exit angle of the second light emitting element is 2B, and a distance between the first light emitting element and the second light emitting element is 2h, which satisfies the following condition: tanA=h/ D2; and tanB=2h/(d1+d2). The light source module of claim 1, wherein a projection length of the first corner optical microstructure pattern on the light incident side decreases in a direction away from the light incident side. The light source module of claim 1, wherein a projection length of the second corner optical microstructure pattern on the light incident side decreases in a direction away from the light incident side. A light guide plate comprising: a light-viewing side; a visible region having an optical pattern, the light-taking capability of the optical pattern linearly increasing from a side adjacent to the light-incident side toward a side away from the light-incident side; a transition region between the light-incident side and the a visual interval; a first corner optical microstructure pattern located adjacent to the transition region in the visible region; and a second corner optical microstructure pattern located in the transition region in front of the first corner optical microstructure pattern . The light guide plate of claim 5, wherein a projection length of the first corner optical microstructure pattern on the light incident side decreases in a direction away from the light incident side. The light guide plate of claim 5, wherein a projection length of the second corner optical microstructure pattern on the light incident side decreases in a direction away from the light incident side.