CN103925524B - The energy-saving backlight module that angle of visibility is adjustable - Google Patents
The energy-saving backlight module that angle of visibility is adjustable Download PDFInfo
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- CN103925524B CN103925524B CN201410154809.XA CN201410154809A CN103925524B CN 103925524 B CN103925524 B CN 103925524B CN 201410154809 A CN201410154809 A CN 201410154809A CN 103925524 B CN103925524 B CN 103925524B
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- micro
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Abstract
The invention discloses the energy-saving backlight module that a kind of angle of visibility is adjustable, comprise the first light source, secondary light source and light guide plate.Wherein, the light that the first light source sends makes liquid crystal display have the first angle of visibility after light guide plate outgoing, and the light that secondary light source sends makes liquid crystal display have the second angle of visibility after light guide plate outgoing.The full width at half maximum number of degrees (FWHM) of the first angle of visibility are within ± 10 °, and the full width at half maximum number of degrees (FWHM) of the second angle of visibility are between ± 60 ° and ± 70 °.The energy-saving backlight module that angle of visibility of the present invention is adjustable can make liquid crystal display switch, to be applicable to different viewing occasions between two kinds of different angle of visibilities.For the occasion only having a people, the energy-saving backlight module that angle of visibility of the present invention is adjustable only need provide forward brightness, thus reduces the energy consumption of liquid crystal display.
Description
Technical field
The present invention relates to a kind of backlight module, particularly relate to the energy-saving backlight module that a kind of angle of visibility is adjustable.
Background technology
The display of liquid crystal display (LCD) to be a kind of with liquid crystal be material.Under electric field action, the change that liquid crystal molecule can arrange, thus impact is by light change wherein, the change of this light can show as the change of light and shade by the effect of polaroid.Like this, by control electric field can light regulating light and shade change, thus display image.At present, liquid crystal display is widely used in the fields such as mobile phone, panel computer, Vehicular display device, TV, wherein most liquid crystal display, LCD TV and part mobile phone all adopt thin film transistor (TFT) (TFT, ThinFilmTransistor) to drive, and they are commonly called TFT-LCD.
TFT-LCD display is non-autonomous luminescence type display, needs additional backlight module to provide planar light source.Backlight module is one of key part and component of panel of LCD, is generally divided into front light formula and backlight type two kinds.Wherein the backlight module of backlight type can according to the requirement of its scale, is divided into side-light type, full run-down type and hollow type three macrostructure according to the position difference of fluorescent tube.For side-light backlight module, adopt light guide plate to form planar light source traditionally, its main member is except light emitting diode (LED) light source, light guide plate, reflector plate, diffusion sheet, also has at least mutually perpendicular light harvesting prismatic lens of two panels, its role is to the visible angle limiting liquid crystal display, most light is made to be outgoing in the scope of ± 30 °-± 60 ° at visual angle, front, to reach the effect of light harvesting blast.
But the visible angle of liquid crystal display being set in (as ± 30 °-± 60 °) in a scope determined is be unfavorable for actual use.In actual use, sometimes only have a people to watch this display, at this time only need to provide enough brightness just can meet the viewing needs of user at the forward of this display; And sometimes have many people and watch this display simultaneously, at this time then need in the polarizers of big angle scope of this display, provide enough brightness to meet the viewing needs of user.Prior art is to provide the liquid crystal display with large visible angle to this way to solve the problem, but such display can cause unnecessary energy consumption when user only has a people.
Therefore, those skilled in the art is devoted to develop a kind of energy-saving backlight module, to realize freely switching between the less angle of visibility and larger angle of visibility of liquid crystal display.
Summary of the invention
Because the above-mentioned defect of prior art, technical problem to be solved by this invention is to provide a kind of energy-saving backlight module, makes liquid crystal display selectively provide two kinds of visible angles by arranging two kinds of light sources.
For achieving the above object, the invention provides the energy-saving backlight module that a kind of angle of visibility is adjustable, comprise the first light source, secondary light source and light guide plate; Described light guide plate is a hexahedron be made up of the first side, the second side, the 3rd side, the 4th side, bottom surface and end face, wherein, described second side and described 4th side in a center of symmetry, described 3rd side becomes axial symmetry with described first side, and described end face and described bottom surface are parallel to each other; Described first light source is close to described first side and is placed, and described secondary light source is close to described 3rd side and is placed;
The described end face of described light guide plate is coated with scattering material.
Further, described second side is provided with the first micro-structural, and described first micro-structural enables to send and the light passing described first side reflexes to described 3rd side from described first light source; Described 3rd side is provided with the second micro-structural, and described second micro-structural enables the light inciding described 3rd side reflex to described bottom surface; Described bottom surface is provided with the 3rd micro-structural, the light inciding described bottom surface is reflexed to described end face by described 3rd micro-structural, and from described end face outgoing, forming surface light source, described area source has the first angle of visibility, and the full width at half maximum number of degrees (FWHM) of described first angle of visibility are within ± 10 °.
Further, described 4th side is provided with the 4th micro-structural, and described 4th micro-structural enables to send and the light passing described 3rd side reflexes to described first side from described secondary light source; Described first side is provided with the 5th micro-structural, described 5th micro-structural enables the light inciding described first side reflex in described 3rd micro-structural of described bottom surface, the light inciding described bottom surface is reflexed to described end face by described 3rd micro-structural, and through described scattering material generation scattering, form the second angle of visibility, the full width at half maximum number of degrees (FWHM) of described second angle of visibility are between ± 60 ° and ± 70 °.
Further, described scattering material is strip or zonal distribution.
Further, described first light source and described secondary light source be light emitting diode, Organic Light Emitting Diode, laser, spontaneous formation or through the light source with high directivity of ovennodulation.
Further, the angle of described second side and described first light source incidence light is the first angle, and described first angle is greater than 0 °.
Further, the angle of described 4th side and described secondary light source incident ray is the second angle, and described second angle is equal with described first angular dimension.
Further, the angle of described 3rd side and vertical plane is the 3rd angle, and described 3rd angle is greater than 0 °.
Further, the angle of described first side and vertical plane is the 4th angle, described 4th angle and described 3rd angle equal and opposite in direction.
Further, described first micro-structural and described 4th micro-structural are the array of multiple sphenoid composition, and each described sphenoid is projected as triangle in described bottom surface, described first micro-structural and described 4th micro-structural in a center of symmetry.
Further, described second micro-structural and described 5th micro-structural are the array of multiple sphenoid composition, and each described sphenoid is projected as triangle in described bottom surface, described second micro-structural and described 5th micro-structural in a center of symmetry.
Further, described sphenoid upper surface is parallelogram, rectangle, square or trapezoidal.
Further, described 3rd micro-structural is the array of multiple triangular prism composition, and each described triangular prism is projected as triangle on described second side or the 4th side.
Further, described first micro-structural, described second micro-structural, described 3rd micro-structural, described 4th micro-structural and described 5th micro-structure surface are coated with total reflection material.
The energy-saving backlight module that angle of visibility of the present invention is adjustable can realize the switching of liquid crystal display between two kinds of angle of visibilities, wherein a kind of angle of visibility is less, be suitable for the occasion that a people watches liquid crystal display, another kind of angle of visibility is comparatively large, is suitable for the occasion that many people watch liquid crystal display simultaneously.Like this, the energy-saving backlight module of the application of the invention, need not provide the light of wide-angle when a people watches liquid crystal display and only need provide forward brightness, thus reducing the energy consumption of liquid crystal display, reaching energy-conservation object.
Accompanying drawing explanation
Fig. 1 is the isometric view of a preferred embodiment of the present invention;
Fig. 2 is the top view of a preferred embodiment of the present invention;
Fig. 3 be a preferred embodiment of the present invention along the partial sectional view in the 1-1 cross section in Fig. 1 and realize the first visible angle time the schematic diagram in light transmition path;
Fig. 4 is the schematic diagram in middle light transmition path when realizing the first visible angle embodiment illustrated in fig. 2;
Fig. 5 is the schematic diagram in middle light transmition path when realizing the first visible angle embodiment illustrated in fig. 3;
Fig. 6 is the schematic diagram in light transmition path when realizing the second visible angle in present pre-ferred embodiments;
Detailed description of the invention
Elaborate to embodiments of the invention below in conjunction with accompanying drawing, the present embodiment is implemented under premised on technical solution of the present invention, give detailed embodiment and concrete operating process, but scope is not limited to following embodiment.
In a preferred embodiments of the present invention, as Figure 1-3, the energy-saving backlight module that a kind of angle of visibility is adjustable, comprises the first light source 10, secondary light source 11 and light guide plate; First light source 10 and secondary light source 11 are light emitting diode, in the embodiment that other is alternative can also for Organic Light Emitting Diode, laser, spontaneous formation or through the light source with high directivity of ovennodulation.Light guide plate is a hexahedron be made up of the first side 32, side 31, second, the 3rd side 33, the 4th side 34, bottom surface 21 and end face 20.Wherein, the second side 32 and the 4th side 34 in a center of symmetry, and the second side 32 and the first light source incidence light have angle, and are designated as the first angle [alpha]
1; 4th side 34 has angle with secondary light source incident ray, is designated as the second angle [alpha]
2, α
1and α
2equal and opposite in direction and be all greater than 0 °.3rd side 33 and 31 one-tenth, the first side axial symmetry, and the 3rd side 33 has angle with vertical plane, is designated as the 3rd angle [alpha]
3, the first side 31 also has angle with vertical plane, is designated as the 4th angle [alpha]
4, α
3and α
4equal and opposite in direction and be all greater than 0 °.End face 20 and bottom surface 21 are parallel to each other.First light source 10 is close to the first side 31 and is placed, and secondary light source 11 is close to the 3rd side 33 and is placed.
The end face 20 of light guide plate is coated with scattering material 90, and this scattering material 90 is in strip or zonal distribution.In the embodiment that other is alternative, scattering material 90 can also first apply on optical thin film, and then sticks in end face 20.
Second side 32 is provided with the first micro-structural, and this first micro-structural is the array of multiple sphenoid 41 composition, and each sphenoid 41 is projected as triangle in bottom surface, and each upper surface of sphenoid 41 and the angle of lower surface are designated as β
1, the upper surface of sphenoid 41 can be parallelogram, rectangle, square or trapezoidal.
3rd side 32 is provided with the second micro-structural, and the second micro-structural is the array of multiple sphenoid 42 composition, and each sphenoid 42 is projected as triangle in bottom surface, and each upper surface of sphenoid 42 and the angle of lower surface are designated as β
2, the upper surface of sphenoid 42 can be parallelogram, rectangle, square or trapezoidal.
Bottom surface 21 is provided with the 3rd micro-structural, and the 3rd micro-structural is the array of multiple triangular prism 43 composition, and each triangular prism 43 is projected as triangle on the second side 32 or the 4th side 34, and two sides 81 and 82 of triangular prism 43 and the angle of its bottom surface are designated as β respectively
3and β
4.
4th side 34 is provided with the 4th micro-structural, and the 4th micro-structural is the array of multiple sphenoid 44 composition, and each sphenoid 44 is projected as triangle in bottom surface 21, and the upper surface of sphenoid 44 can be parallelogram, rectangle, square or trapezoidal; 4th micro-structural and the first micro-structural in a center of symmetry.
First side 31 is provided with the 5th micro-structural, and the 5th micro-structural is the array of multiple sphenoid 45 composition, and each sphenoid 45 is projected as triangle in bottom surface, and the upper surface of sphenoid 45 can be parallelogram, rectangle, square or trapezoidal; 5th micro-structural and the second micro-structural in a center of symmetry.
In preferred embodiment of the present invention, the first micro-structural, the second micro-structural, the 3rd micro-structural, the 4th micro-structural and the 5th micro-structure surface are coated with total reflection material.
Fig. 4 is the schematic diagram in light transmition path when realizing the first visible angle in the adjustable energy-saving backlight module top view of the angle of visibility of preferred embodiment of the present invention, as shown in the figure, emit beam 100 through the first side 31 from the first light source 10, incide the upper surface of the sphenoid 41 in the first micro-structural and total reflection occurs become light 200; Light 200 incides the upper surface of the sphenoid 42 in the second micro-structural and total reflection occurs becomes light 300.At the upper surface of sphenoid 41, light 100 is designated as θ with the angle of normal 51
1, light 200 is designated as θ with the angle of normal 51
2; At the upper surface of sphenoid 42, light 200 is designated as θ with the angle of normal 52
3, light 300 is designated as θ with the angle of normal 52
4, and light 200 is designated as δ with the angle of the lower surface of sphenoid 42, light 200 is designated as γ with the angle of light 100.Each angle meets following formula:
α
1=tan
-1(H
cls/L)
γ=tan
-1(W/L)
δ=tan
-1(L/W)
θ
1=θ
2=(180-γ)/2
θ
3=θ
4=(90-δ)/2
β
1=90-α
1-θ
1
β
2=90-δ-θ
3
In formula, L is the length of the second side 32, and W is the length of the 3rd side 33, H
clsit is the width of the first light source 10.
Fig. 5 is the adjustable energy-saving backlight module of the angle of visibility of preferred embodiment of the present invention along the schematic diagram in light transmition path when realizing the first visible angle in the sectional view in the 1-1 cross section in Fig. 1, as shown in the figure, light 200 incides the upper surface of the sphenoid 42 in the second micro-structural and total reflection occurs becomes light 300, and light 300 incides the surface 82 of triangular prism 43 and total reflection occurs becomes 400; Finally, as shown in Figure 3, light 400 is from end face 20 outgoing, and form first surface light source, for LCDs provides the first angle of visibility, the full width at half maximum number of degrees (FWHM) of the first angle of visibility are within ± 10 °.At the upper surface of sphenoid 42, light 200 is designated as ω with the angle of normal 53
1, light 300 is designated as ω with the angle of normal 53
2, and light 300 is designated as with vertical direction angle
on the surface 82 of triangular prism 43, light 300 is designated as ω with the angle of normal 54
3, light 300 and horizontal direction angle are designated as ψ, and light 400 is designated as ω with the angle of normal 54
4.Each angle meets following formula:
ψ=tan
-1(H/L)
ω
3=ω
4
β
3=β
4=90-ψ-ω
3
In formula, L is the length of the second side 32, and H is the height of light guide plate, i.e. the distance of bottom surface 21 and end face 20.
Fig. 6 is the adjustable energy-saving backlight module of the angle of visibility of preferred embodiment of the present invention along the schematic diagram in light transmition path when realizing the second visible angle in the sectional view in the 1-1 cross section in Fig. 1, the light sent by secondary light source 11 is reflexed to bottom surface 21 by the 4th micro-structural on the 4th side 34 and the 5th micro-structural on the first side 31 successively, then end face 20 is reflexed to by the 3rd micro-structural on bottom surface 21, run into the after 90s by the scattering material of strip or zonal distribution of end face 20, light 500 scatters completely, for LCDs provides the planar light source of the second angle of visibility, the full width at half maximum number of degrees (FWHM) of the second angle of visibility are between ± 60 ° and ± 70 °.
The energy-saving backlight module that the angle of visibility of the present embodiment is adjustable is when realizing the first angle of visibility, and under same brightness, the energy consumed is much smaller than energy resource consumption when realizing the second angle of visibility.The energy-saving backlight module that angle of visibility of the present invention is adjustable can realize the switching of liquid crystal display between the first angle of visibility and the second angle of visibility, like this, the energy-saving backlight module of the application of the invention, the light of wide-angle need not be provided when a people watches liquid crystal display and forward brightness only need be provided, thus reduce the energy consumption of liquid crystal display, reach energy-conservation object.
More than describe preferred embodiment of the present invention in detail.Should be appreciated that the ordinary skill of this area just design according to the present invention can make many modifications and variations without the need to creative work.Therefore, all technical staff in the art, all should by the determined protection domain of claims under this invention's idea on the basis of existing technology by the available technical scheme of logical analysis, reasoning, or a limited experiment.
Claims (3)
1. the energy-saving backlight module that angle of visibility is adjustable, is characterized in that comprising the first light source, secondary light source and light guide plate; Described light guide plate is a hexahedron be made up of the first side, the second side, the 3rd side, the 4th side, bottom surface and end face, wherein, described second side and described 4th side in a center of symmetry, described 3rd side becomes axial symmetry with described first side, and described end face and described bottom surface are parallel to each other; Described first light source is close to described first side and is placed, and described secondary light source is close to described 3rd side and is placed;
Described second side and described first light source incidence light have angle, and are designated as the first angle [alpha]
1; Described 4th side and described secondary light source incident ray have angle, and are designated as the second angle [alpha]
2, α
land α
2equal and opposite in direction and be all greater than 0 °; Described 3rd side and vertical plane have angle, and are designated as the 3rd angle [alpha]
3, described first side also has angle with vertical plane, is designated as the 4th angle [alpha]
4, α
3and α
4equal and opposite in direction and be all greater than 0 °;
The described end face of described light guide plate is coated with scattering material, and described scattering material is strip or zonal distribution;
Described second side is provided with the first micro-structural, and described first micro-structural enables to send and the light passing described first side reflexes to described 3rd side from described first light source; Described 3rd side is provided with the second micro-structural, and described second micro-structural enables the light inciding described 3rd side reflex to described bottom surface; Described bottom surface is provided with the 3rd micro-structural, the light inciding described bottom surface is reflexed to described end face by described 3rd micro-structural, and from described end face outgoing, forming surface light source, described area source has the first angle of visibility, and the full width at half maximum number of degrees (FWHM) of described first angle of visibility are within ± 10 °; Described 4th side is provided with the 4th micro-structural, and described 4th micro-structural enables to send and the light passing described 3rd side reflexes to described first side from described secondary light source; Described first side is provided with the 5th micro-structural, described 5th micro-structural enables the light inciding described first side reflex in described 3rd micro-structural of described bottom surface, the light inciding described bottom surface is reflexed to described end face by described 3rd micro-structural, and through described scattering material generation scattering, form the second angle of visibility, the full width at half maximum number of degrees (FWHM) of described second angle of visibility are between ± 60 ° and ± 70 °;
Described first micro-structural is the array of multiple sphenoid composition, each sphenoid is projected as triangle in bottom surface, described second micro-structural is the array of multiple sphenoid composition, each sphenoid is projected as triangle in bottom surface, described 3rd micro-structural is the array of multiple triangular prism composition, each triangular prism is projected as triangle on the second side or the 4th side, described 4th micro-structural is the array of multiple sphenoid composition, each sphenoid is projected as triangle in bottom surface, described 5th micro-structural is the array of multiple sphenoid composition, each sphenoid is projected as triangle in bottom surface, described 4th micro-structural and described first micro-structural in a center of symmetry, described 5th micro-structural and described second micro-structural in a center of symmetry.
2. the energy-saving backlight module that angle of visibility as claimed in claim 1 is adjustable, it is characterized in that, described first light source and described secondary light source are Organic Light Emitting Diode or laser.
3. the energy-saving backlight module that angle of visibility as claimed in claim 1 is adjustable, it is characterized in that, described first micro-structural, described second micro-structural, described 3rd micro-structural, described 4th micro-structural and described 5th micro-structure surface are coated with total reflection material.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410154809.XA CN103925524B (en) | 2014-04-17 | 2014-04-17 | The energy-saving backlight module that angle of visibility is adjustable |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410154809.XA CN103925524B (en) | 2014-04-17 | 2014-04-17 | The energy-saving backlight module that angle of visibility is adjustable |
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| CN103925524A CN103925524A (en) | 2014-07-16 |
| CN103925524B true CN103925524B (en) | 2016-03-09 |
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107479219A (en) * | 2016-06-08 | 2017-12-15 | 南京博昱光电科技有限公司 | Planar light source device and liquid crystal display device |
| CN105911637B (en) * | 2016-07-01 | 2019-05-03 | 京东方科技集团股份有限公司 | Light guide plate, backlight module and display device |
| CN108319071B (en) * | 2017-01-17 | 2021-09-28 | 群创光电股份有限公司 | Display device |
| CN112764151B (en) * | 2021-01-29 | 2023-01-17 | 马鞍山晶智科技有限公司 | Surface light source device and liquid crystal display device |
| CN113835247B (en) * | 2021-09-30 | 2023-09-15 | 上海天马微电子有限公司 | Display module, driving method thereof, display device and vehicle |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102759051A (en) * | 2012-07-18 | 2012-10-31 | 上海交通大学 | Energy-saving backlight module with adjustable viewing angle based on collimation backlight |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI245931B (en) * | 2004-05-07 | 2005-12-21 | Ace T Corp | Light guide panel whose structure is like a triangular prism |
| JP5011151B2 (en) * | 2008-02-12 | 2012-08-29 | 株式会社日立製作所 | Liquid crystal display equipment |
| KR20110076275A (en) * | 2009-12-29 | 2011-07-06 | 서울반도체 주식회사 | Back light unit using led |
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2014
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102759051A (en) * | 2012-07-18 | 2012-10-31 | 上海交通大学 | Energy-saving backlight module with adjustable viewing angle based on collimation backlight |
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