CN201448680U

CN201448680U - LED backlight device

Info

Publication number: CN201448680U
Application number: CN2009200340652U
Authority: CN
Inventors: 张小宁; 丁兴隆; 姜凤山; 刘钱飞; 马俊龙; 刘纯亮
Original assignee: Xian Jiaotong University; Irico Group Corp
Current assignee: Xian Jiaotong University; Irico Group Corp
Priority date: 2009-07-31
Filing date: 2009-07-31
Publication date: 2010-05-05
Anticipated expiration: 2019-07-31

Abstract

The utility model discloses an LED backlight device; reflecting material is coated on the back surface and the side surface of a light guide plate, a groove for arranging an LED lamp tube is arranged on the corresponding surface of the light guide plate and the LED lamp tube, and the groove is designed by taking all parameters of the LED lamp tube into account, and the reflecting material which is the same as the material at the bottom part of the light guide plate is coated on the inner wall of the groove, so as to ensure the light rays of the LED lamp tube to be utilized fully and lead the light brightness at the glaring surface of the light guide plate to be uniform and consistent.

Description

A kind of LED-backlit source apparatus

Technical field

The utility model relates to a kind of light emitting diode (hereinafter to be referred as LED) backlight arrangement, relates in particular to a kind ofly in conjunction with LGP and reflector characteristic, obtains the uniform LCD of luminosity (hereinafter to be referred as LCD) backlight arrangement.

Background technology

Along with the development of technology, LCD has become the flat-panel display device of main flow at present, yet because liquid crystal itself does not possess emitting characteristics, backlight must be the indispensable important component part of LCD.The performance of backlight has directly determined every indexs such as brightness, color and power consumption of LCD.

The backlight that is used for LCD at present mainly is CCFL (CCFL), but comparatively speaking, and it is low, low in energy consumption to use LED to have a driving voltage as the backlight of LCD, and color reducibility is good, and environmental suitability is strong, advantages such as no mercury pollution.Under the present case, the LED-backlit source structure that is used for LCD has two kinds of side entering type and straight-down negatives, and side entering type generally is used for the LCD of small-medium size, and the LED-backlit source of large-scale LCD is generally the straight-down negative structure.

In the side entering type structure, generally can make full use of the structure of original CCFL module backlight, but in the straight-down negative structure, because LED encapsulation, circuit board assemble isostructural influence, therefore cause the uniformity of backlight to reduce greatly, be necessary to propose a kind ofly can make full use of LED and even brightness LED-backlit source apparatus.

Incidence surface and the exiting surface described among the patent CN 101206280A in backlight all have groove, incidence surface be one by rectangle, square, trapezoidal, triangle, semicircle or arbitrary curve around, rotating shaft through LGP incidence surface and exiting surface center rotates and the rotary body of formation, exiting surface is also the same with incidence surface to be a rotary body that the rotation of certain planar graph forms, and scribble reflecting material on the exiting surface groove, this patent is also mentioned directly reflectance coating is plated on the backlight bottom surface in addition.This patent is considered the own design that combines of LGP incidence surface and LED, but what solve in the processing of incidence surface groove is insufficient, and do not consider the relation of incidence surface groove and various LED lamp tube structures, in the integrally-built processing of LGP, do not consider to reduce leaking of LED light how better in addition yet.

Summary of the invention

The purpose of this utility model is to propose a kind of LED-backlit source structure, by the compound and structure optimization of LGP and reflector, reduces the light loss of LED lamp, makes full use of the light that LED sends, and the backlight luminosity is evenly distributed.

The LED-backlit device that the utility model proposes is achieved in that

Do not use reflecting plate in the backlight arrangement, the LED position is removed on circuit board (hereinafter referred to as the LED arrangement board) surface that a plurality of LED are installed all be coated with the last layer reflecting material, bottom surface of light guide plate and LED arrangement board are close to, the light that the LED arrangement board sends is after the reflection of LED inner surface reflecting material, enter the LGP internal mix, LGP is reserved corresponding grooves in the position of corresponding LED according to encapsulation shape size and the LED rising angle of LED in addition, groove is divided into two parts up and down, the groove lower inner wall is close to the LED fluorescent tube, groove top and the bottom inwall all scribbles reflecting material. and lower part groove cross section figure is consistent with LED fluorescent tube encapsulation shape itself, whole groove bottom is divided into cross-sectional view shape longitudinal extension gained cylinder, the height of lower part groove need be considered factors such as the rising angle of LED fluorescent tube and LED fluorescent tube transverse width, can be through calculating. the purpose of lower part reflecting material that groove surfaces is coated with is to make light to the LGP internal reflection, the LGP internal light material reflected back LGP inside that is reflected is carried out light and is mixed. and the top of groove is divided into the handstand cylinder, be that upper surface is bigger than lower surface area, this cylinder cross section is identical with LED fluorescent tube exiting surface shape of cross section, height of column need be considered LED fluorescent tube rising angle and LED fluorescent tube transverse width, but the high computational of engagement groove bottom obtains. the upper portion side wall of groove scribbles the double-sided reflecting material, can make the luminous process groove inwall reflection of LED in the groove vertically enter LGP on the one hand, the LGP internal light reflects through the groove inwall on the other hand, returning LGP inside and carry out the light mixing. whole LGP can be divided into two parts up and down according to the position of groove: lower guide tabula rasa height is consistent with groove lower part height, its shape of cross section and groove lower cross section are interosculated, form a planar graph, shape of cross section is by square, rectangle, the wave that arc and arc combine is linear, the perhaps planar graph that combines of other arbitrary curve sections. LGP top height is by groove upper height and module shape backlight decision, its shape of cross section is the planar graph that groove top cross section interosculates and forms, it can be square, rectangle, the wave that arc and arc combine is linear, the perhaps planar graph that combines of other arbitrary curve sections. LGP is except that upper surface and lower surface, wall all scribbles reflecting material, and the LGP internal light can only be mixed in LGP inside under the reflecting material effect.

As a kind of simplification of the present utility model, the area of LGP top and the bottom all can be done bigger, thereby whole LGP cross section up and down is a rectangle, and it is trapezoidal that vertical four sides, the top of LGP are handstand, and vertical four sides, LGP bottom are square or rectangle.

The back lighting device that the utility model proposed has following advantage:

(1) simplified back light module unit structure, made the module assembling of LED-backlit source simple.

(2) reduce LED fluorescent tube light and leaked, improved the utilization rate of the light of LED fluorescent tube.

(3) light that enters LGP inside can fully mix, and guarantees that the brightness of LGP exiting surface is evenly good.

Description of drawings

Fig. 1 is the side view of the LED-backlit device that the utility model proposes;

Fig. 2 is the profile of the LED-backlit device that the utility model proposes;

Fig. 3 A and Fig. 3 B are respectively the side view and the vertical views of the described LGP groove of first embodiment of the utility model;

Fig. 4 A and Fig. 4 B are respectively the side view and the vertical views of second described LGP groove of embodiment of the utility model;

Fig. 5 A and Fig. 5 B are respectively the side view and the vertical views of the 3rd the described LGP groove of embodiment of the utility model;

The specific embodiment

See figures.1.and.2, do not have reflector in the module backlight, LGP is pressed on the LED arrangement board 140, and LED arrangement board 140 surfaces all scribble reflecting material except that the position that the LED fluorescent tube takies, and the side 120 of LGP also scribbles reflecting material.The light that enters LGP mixes fully in LGP inside under the reflex of the side 120 of LED arrangement board 140 and LGP, thus the brightness uniformity that assurance is gone out from LGP upper surface 110.Whole LGP also is divided into two parts up and down according to the division methods up and down of groove, lower guide tabula rasa height is consistent with the groove lower height, its shape of cross section is to be that the wave that combined by square, rectangle, arc and arc is linear, perhaps the planar graph that combines of other arbitrary curve sections; LGP upper height h1 can try to achieve according to groove upper height and LED-backlit module shape, and its shape of cross section is that the wave that is combined by square, rectangle, arc and arc is linear, perhaps the planar graph that combines of other arbitrary curve sections.

Fig. 3 A and Fig. 3 B are first embodiment of the present utility model.With reference to Fig. 3 A, LED fluorescent tube 160 is embedded in the groove of LGP, and groove lower inner wall 150 scribbles reflecting material, and the light of LGP inside returns LGP and mixes under the reflecting material effect.The magnitude range of the side of LED fluorescent tube 160 and the spacing x of groove is 0-25mm, considers the width d of LED cross section, and the bottom portion of groove width is (x+d).The reflecting material that inwall 130 surfaces on groove top scribble, the light that the LED fluorescent tube is sent vertically enters LGP after the reflection of groove upper inside wall, make the light of LGP inside return LGP inside on the other hand after the reflection of groove upper inside wall.Beam angle according to LED fluorescent tube 160, after the light that guarantees edge is through 130 reflections of groove inwall, can vertically inject on the basis of LGP 100, calculate groove top opening angle b, thereby calculate the groove lower height, be h2=H+y/tan (b), the span of y is 0-100mm.The height E span of distance from top LED fluorescent tube 160 exiting surfaces on groove top is 0.1-1000mm.

With reference to Fig. 3 B, groove lower cross section shape is consistent with the encapsulation shape of LED fluorescent tube 160, and LED fluorescent tube 160 is encapsulated as square or cuboid in the present embodiment, thereby the groove bottom also is square or cuboid, and height is highly identical with LED.The shape on groove top and LED fluorescent tube 160 exiting surface shapes are consistent, the exiting surface of LED fluorescent tube 160 is square or rectangle in the present embodiment, thereby groove top cross section figure is square or rectangle, and the longitudinal cross-section figure on whole groove top is to go up the prismatoid structure of bottom side length greater than the length of side of going to the bottom.Consider the arrangement pitches of LED fluorescent tube 160, LGP lower cross section and top cross section are square or rectangle in the present embodiment.

Fig. 4 A and Fig. 4 B are second embodiment of the present utility model.With reference to Fig. 4 A, LED fluorescent tube 160 is encapsulated as cylinder or oval cylinder in the present embodiment, and exiting surface is circular or oval.Thereby in the present embodiment, it is identical with LED fluorescent tube height that the groove bottom is divided into height, and the cross section figure is circular or oval cylinder; Groove top is divided into the cone or the elliptic cone body structure at a handstand excision top, and promptly upper surface area is greater than the lower surface area.LED fluorescent tube 160 is embedded in the groove of LGP, and groove lower inner wall 150 scribbles reflecting material, and the light of LGP inside returns LGP and mixes under the reflecting material effect.The magnitude range of the side of LED fluorescent tube 160 and the spacing x of groove is 0-25mm, considers the width d of LED cross section, and the bottom portion of groove width is (x+d).The reflecting material that inwall 130 surfaces on groove top scribble, the light that the LED fluorescent tube is sent vertically enters LGP after the reflection of groove upper inside wall, make the light of LGP inside return LGP inside on the other hand after the reflection of groove upper inside wall.Beam angle according to LED fluorescent tube 160, after the light that guarantees edge is through 130 reflections of groove inwall, can vertically inject on the basis of LGP 100, calculate groove top opening angle b, thereby calculate the groove lower height, be h2=H+y/tan (b), the span of y is 0-100mm.The height E span of distance from top LED fluorescent tube 160 exiting surfaces on groove top is 0.1-1000mm.

With reference to Fig. 4 B, LGP lower part shape of cross section in the present embodiment is consistent with the following stated shape, and promptly to close the graphics shape that the planar graph that forms is formed by stacking consistent with each groove lower part cross section of LED arrangement board edge and each cross section center of circle link group.LGP top shape of cross section is consistent with the following stated shape, and promptly to close the graphics shape that the planar graph that forms is formed by stacking consistent with each groove top cross section of LED arrangement board edge and each cross section center of circle link group.

Fig. 5 A and Fig. 5 B are the 3rd embodiment of the utility model. with reference to Fig. 5 A, LED fluorescent tube 160 itself is encapsulated as triangular prism or N prism in the present embodiment, exiting surface is triangle or N limit shape, thereby Ben Tu is identical with Fig. 3 A. in the present embodiment, it is identical with LED fluorescent tube height that the groove bottom is divided into height, and the cross section figure is the cylinder of triangle or N limit shape; Groove top is divided into a handstand tri-prismoid or N prism structure, be that upper surface area is embedded in the groove of LGP greater than lower surface area .LED fluorescent tube 160, groove lower inner wall 150 scribbles reflecting material, the light of LGP inside is under the reflecting material effect, the magnitude range of returning the spacing x of the side of LGP mixing .LED fluorescent tube 160 and groove is 0-25mm, consider the width d of LED cross section, the bottom portion of groove width is (x+d). the reflecting material that inwall 130 surfaces on groove top scribble, the light that the LED fluorescent tube is sent vertically enters LGP after the reflection of groove upper inside wall, make the light of LGP inside after the reflection of groove upper inside wall, return LGP inside on the other hand. according to the beam angle of LED fluorescent tube 160, after the light that guarantees edge is through 130 reflections of groove inwall, can vertically inject on the basis of LGP 100, calculate groove top opening angle b, thereby calculate the groove lower height, be h2=H+y/tan (b), the span of y is that the height E span of distance from top LED fluorescent tube 160 exiting surfaces on 0-100mm. groove top is 0.1-1000mm.

With reference to Fig. 5 B, LGP lower part shape of cross section in the present embodiment is consistent with the following stated shape, and promptly the graphics shape that is formed by stacking with planar graph that each groove lower part cross section of LED arrangement board edge and each cross section unfaithful intention line combine is consistent.LGP top shape of cross section is consistent with the following stated shape, and promptly the graphics shape that is formed by stacking with planar graph that each groove top cross section of LED arrangement board edge and each cross section unfaithful intention line combine is consistent.

The LED-backlit source apparatus that the utility model proposes is work like this: at first, the LED fluorescent tube is embedded in the groove of LGP, injects in the LGP after luminous process the first half groove inwall reflection of LED fluorescent tube; Then, the light that enters LGP inside is at LED arrangement board surface reflecting material, LGP groove inwall reflecting material, and under the effect of LGP offside reflection material, fully mix in LGP inside, thereby guarantee exiting surface brightness uniformity.

Claims

1. LED-backlit source apparatus, it is characterized in that, reflecting material is coated in LED arrangement board surface, LED fluorescent tube light enters LGP under the reflection of LED arrangement board, the LGP incidence surface leaves the groove that holds the LED fluorescent tube, the inwall of groove scribbles reflecting material, and LGP is except that all scribbling reflecting material around the upper and lower surface.

2. LED-backlit source apparatus according to claim 1, it is characterized in that: groove is divided into two parts up and down, groove lower part inwall is close to the LED fluorescent tube, the groove bottom is divided into a cylinder, the shape of cross section of groove lower part is identical with LED fluorescent tube encapsulation shape, shape of cross section can be square, rectangle, the wave that arc and arc combine is linear, the perhaps planar graph that combines of other arbitrary curve sections, groove lower part inwall scribbles reflecting material, the light of LGP inside is under the reflection of groove lower part inwall, returning LGP inside mixes, groove the first half is a handstand cylinder, be that upper surface area is greater than lower surface, groove top shape of cross section is consistent with LED fluorescent tube exiting surface shape, shape of cross section can be square, rectangle, the wave that arc and arc combine is linear, the perhaps planar graph that combines of other arbitrary curve sections, and groove top inwall scribbles the double-sided reflecting material.

3. LED-backlit source apparatus according to claim 1, it is characterized in that: whole LGP also is divided into two parts up and down according to the division up and down of groove, lower part LGP height is consistent with groove lower part height, its cross section is a planar graph, shape of cross section can be square, rectangle, the wave that arc and arc combine is linear, the perhaps planar graph that combines of other arbitrary curve sections, the LGP cross section is a planar graph, shape of cross section can be square, rectangle, the wave that arc and arc combine is linear, the perhaps planar graph that combines of other arbitrary curve sections, LGP is except that upper surface and lower surface, all scribble reflecting material all around, LGP internal light return conduit intralamellar part under the reflecting material effect mixes.

4. LED-backlit source apparatus according to claim 1, it is characterized in that: LGP top and the bottom cross section all is designed to square or rectangle, it is trapezoidal that vertical four sides, the top of LGP are handstand, and vertical four sides, LGP lower part are square or rectangle.