CN106415378A - Edge-light type backlight unit and reflective tape member - Google Patents

Abstract

In order to provide an edge-light type backlight unit in which light utilization efficiency is increased and luminosity improvement is accelerated by a beam of light output from a light source being accurately incidented inside a light guide film, an edge-light type backlight unit according to the present invention: is equipped with a light guide film having an average thickness of 100-600 microns inclusive, and one or a plurality of thin light sources arranged facing one or a plurality of end surfaces of the light guide film; outputs a beam of light, which is output from the thin light source, from a surface of the light guide film; and is also equipped with a first reflective tape arranged so as to cover the surface side of light guide film at the edges of the side thereof to which the one or a plurality of thin light sources are arranged. The first reflective tape may be arranged so as to cover the surface side of a gap between the light guide film and the one or a plurality of thin light sources.

Description

Edge-lit backlight unit and reflection band member

Technical field

The present invention relates to edge-lit backlight unit and reflection band member.

Background technology

Liquid crystal indicator has been popularized makes its luminous backlight mode from back side illuminaton liquid crystal layer, in the rear side of liquid crystal layer The back light units such as side-light type, straight-down negative are installed.Normally, as shown in figure 17, described edge-lit backlight unit 110 possesses：Join Put the reflector plate 115 on the surface of top board 116, the configuration light guide plate 111 on the surface of described reflector plate 115, configure described The light source 117 of the optical sheet 112 on the surface of light guide plate 111 and the end face irradiation light to described light guide plate 111 is (referring to Japan specially Sharp Publication JP 2010-177130).In the edge-lit backlight unit 110 of this Figure 17, as light source 117, for example may be used So that using multiple LED, this light source 117 irradiates and incides the light of light guide plate 111, propagate in light guide plate 111.The light of this propagation A part, from the back side of light guide plate 111 project, reflected by reflector plate 115 and be again incident on light guide plate 111.

Additionally, possessing the liquid crystal indicator of such liquid crystal display part, in order to improve its portability, convenience and require Slimming and lightweight, are accompanied by this, also require that slimming to liquid crystal display part.Particularly the thick in housing is 21mm It is desirable to the thickness of liquid crystal display part is about 4mm to 5mm, to being assembled in liquid crystal display in following super-thin portable terminal Edge-lit backlight unit in portion requires further slimming.

Prior art literature

Patent documentation

Patent documentation 1：Japanese Laid-Open Patent Publication 2010-177130

Content of the invention

The technical problem to be solved in the present invention

In the edge-lit backlight unit of such extra-thin portable terminal, because the thickness of liquid crystal display part is institute State the thickness of degree, so also requiring that further slimming for light guide plate.From such point, as described The light guide plate of the edge-lit backlight unit of extra-thin portable terminal is it is proposed that a kind of scheme：Replacement section is approximate wedge shape The larger conventional light guide plate of thickness, using the light guiding film of the film like with generally uniform thickness.

The present inventor, in the case of employing the liquid crystal indicator possessing such light guiding film, finds and conventional liquid Crystal device is compared, and there is the situation of luminance-reduction.The present inventor has carried out the result of wholwe-hearted research for this shortcoming, distinguishes , due to promoting the slimming of light guiding film, do not make the light from light source irradiation substantially entirely incident from the end face of light guiding film To in light guiding film.

The present invention is in view of such situation and the invention made, it is an object of the invention to provide a kind of side-light backlight Unit, it passes through to make the light irradiating from light source rightly incide in light guiding film, it is possible to increase the utilization ratio of light, can promote The raising of brightness.Additionally, further object is that providing a kind of reflection band member, it can make from light source irradiation Light rightly incides in light guiding film.

Solve the technical scheme of technical problem

In order to solve the problems, such as the present invention a kind of edge-lit backlight unit of offer that is described and making, it possesses：Light guiding film, Average thickness is less than more than 100 μm 600 μm；And one or more low profile light source, with one or many with described light guiding film The relative mode of individual end face configures, described edge-lit backlight unit make from described low profile light source project light from described light guiding film Surface project, described edge-lit backlight unit possesses first zone of reflections, and described first zone of reflections is to cover described light guiding film The mode of the face side of one or more of low profile light source side edge configures.

Typically, since the just diffusion light projecting from light sources such as LED, so in edge-lit backlight unit, penetrating from light source A part for the light going out does not impinge on the end face of light guiding film or does not rightly propagate in light guiding film, thus losing. Additionally, the loss of such light becomes more notable with the filming more promoting light guiding film.On the other hand, the side-light type of the present invention Back light unit, because possessing first zone of reflections, described first zone of reflections is to cover one or more low profile light source sides of light guiding film The mode of the face side of ora terminalis configures, it is possible to making the light projecting from one or more low profile light sources be reflected by described first Band reflection, and can make to be incided in light guiding film by the light of described first zone of reflections reflection.Thus, the side-light type of the present invention Back light unit, though light guiding film average thickness be less than more than 100 μm 600 μm so less in the case of, by make from The light that one or more low profile light sources irradiate rightly incides in light guiding film it is also possible to improve the utilization ratio of light, promotion The raising of brightness.

Preferably, described first zone of reflections is to cover between one or more of low profile light sources and described light guiding film The mode of the face side in space configures.Accordingly, because described first zone of reflections with cover one or more of low profile light sources with The mode of the face side in the space between described light guiding film configures, it is possible to making to project from one or more low profile light sources and compare More reflected and incide by first zone of reflections to the light of face side diffusion to the light guiding film end face relative with low profile light source and lead In light film.

Preferably, described edge-lit backlight unit is also equipped with second zone of reflections, and described second zone of reflections is described to cover The mode of the rear side in the space between one or more low profile light sources and described light guiding film configures.Accordingly, because described sidelight Formula back light unit is also equipped with second zone of reflections, and described second zone of reflections is led with described with covering one or more of low profile light sources The mode of the rear side in the space between light film configures, it is possible to making to project from one or more low profile light sources and compare to leaded light The end face relative with low profile light source of film more support or oppose surface side diffusion light reflected and incided in light guiding film by second zone of reflections.

Preferably, described light guiding film has the prism portion that section is triangle, and described prism portion is to be configured with described one The mode that individual or multiple low profile light source end edge surface is more gradually increased the closer to end edge side thickness is formed, described first zone of reflections Configured in the way of covering the surface in described prism portion.Accordingly, because described light guiding film has the prism portion that section is triangle, Described prism portion is more gradually increased the closer to end edge side thickness with the end edge surface being configured with one or more of low profile light sources Mode formed, so pass through described prism portion, can make the light of light guiding film incident end face area increase, can make from The light that low profile light source projects easily incides light guiding film.Additionally, because described first zone of reflections is to cover described prism portion The mode on surface configures, it is possible to preventing the light inciding described prism portion from directly injecting to light guiding film through prism portion Outward.

Preferably, described first zone of reflections possesses reflecting layer, and described reflecting layer has：Matrix, with resin as main constituent； And Chinese white, it is contained in described matrix.Accordingly, because described first zone of reflections possesses reflecting layer, described reflecting layer has： Matrix, with resin as main constituent；And Chinese white, it is contained in described matrix, so easily being formed at the back side in this reflecting layer Result from multiple minute asperities of Chinese white, the light projecting and being irradiated to first zone of reflections from low profile light source can be made to pass through The plurality of minute asperities appropriateness scatters.Therefore, by the light of the first zone of reflections reflection to the incident angle of incidence of light guiding film It is suitably adjusted, it is possible to increase the light inciding in light guiding film is propagated in light guiding film.

Preferably, described first zone of reflections is also equipped with adhesive phase, and described adhesive is laminated on described reflecting layer, institute layer by layer State first zone of reflections and pass through described adhesive layer and one or more of low profile light sources and the bonding of described light guiding film.Thus, Because described first zone of reflections is also equipped with adhesive phase, described adhesive is laminated on described reflecting layer, described first zone of reflections layer by layer By described adhesive layer and one or more of low profile light sources and the bonding of described light guiding film, it is possible to prevent light from Spill between first zone of reflections and light guiding film, the light projecting from low profile light source can be made further rightly to incide leaded light Film.

Described first zone of reflections is with false tacky state and one or more of low profile light sources and the bonding of described light guiding film. Accordingly, because described first zone of reflections is glued with one or more of low profile light sources and described light guiding film with false tacky state Closing, it is possible to preventing light from spilling between first zone of reflections and light guiding film, and the configuration of first zone of reflections 14 can be made Become easy with re-pasting.

Additionally, in order to solve the problems, such as that the present invention that is described and making also provides a kind of reflection band member, it is as described First zone of reflections of edge-lit backlight unit uses.

This reflection band member because first zone of reflections as described edge-lit backlight unit uses, it is possible to make from The light that low profile light source irradiates rightly incides in light guiding film.

In addition, " face side " in the present invention refers to the side of beholder when being installed to the liquid crystal indicator, " back side Side " refers to the side contrary with face side." main constituent " refers to the most composition of content, and for example referring to content is more than 50 mass % Composition." false tacky state " refers in lower of room temperature (25 DEG C) with pulling the state being easy to peel off, for example, peel off strong Spend for more than 0.02N/5cm below 5N/5cm, preferably peel strength is more than 0.1N/5cm below 1N/5cm.

Invention effect

Cross as mentioned above, the edge-lit backlight unit of the present invention, by make from light source project light rightly Incide in light guiding film, it is possible to increase the utilization ratio of light, and the raising of brightness can be promoted.Additionally, the zone of reflections structure of the present invention Part, can make the light projecting from light source rightly incide in light guiding film.

Brief description

Fig. 1 is the schematic perspective view of the portable terminal of the first embodiment representing the present invention, and (a) of Fig. 1 represents liquid The state that brilliant display part is opened, (b) of Fig. 1 represents the state that liquid crystal display part is closed.

Fig. 2 is the cross-sectional schematic of the edge-lit backlight unit of the portable terminal representing Fig. 1.

Fig. 3 is the close-up schematic view of the manufacture device of the light guiding film of the back light unit representing Fig. 2.

Fig. 4 is the cross-sectional schematic representing the back light unit of mode different from the back light unit of Fig. 2.

Fig. 5 is the cross-sectional schematic representing the back light unit of mode different from the back light unit of Fig. 2, Fig. 4.

Fig. 6 is the cross-sectional schematic representing the back light unit of mode different from the back light unit of Fig. 2, Fig. 4, Fig. 5.

Fig. 7 is the cross-sectional schematic of the light guiding film of the other embodiment representing the present invention.

Fig. 8 is the cross-sectional schematic representing the back light unit of mode different from the back light unit of Fig. 2, Fig. 4, Fig. 5, Fig. 6.

Fig. 9 is that the section view representing the back light unit of mode different from the back light unit of Fig. 2, Fig. 4, Fig. 5, Fig. 6, Fig. 8 is shown It is intended to.

Figure 10 is to represent cuing open of the back light unit of mode different from the back light unit of Fig. 2, Fig. 4, Fig. 5, Fig. 6, Fig. 8, Fig. 9 Depending on schematic diagram.

Figure 11 is to represent cuing open of the back light unit of mode different from the back light unit of Fig. 2, Fig. 4, Fig. 5, Fig. 6, Fig. 8～10 Depending on schematic diagram.

Figure 12 is to represent cuing open of the back light unit of mode different from the back light unit of Fig. 2, Fig. 4, Fig. 5, Fig. 6, Fig. 8～11 Depending on schematic diagram.

Figure 13 is to represent cuing open of the back light unit of mode different from the back light unit of Fig. 2, Fig. 4, Fig. 5, Fig. 6, Fig. 8～12 Depending on schematic diagram.

Figure 14 is to represent cuing open of the back light unit of mode different from the back light unit of Fig. 2, Fig. 4, Fig. 5, Fig. 6, Fig. 8～13 Depending on schematic diagram.

Figure 15 is to represent cuing open of the back light unit of mode different from the back light unit of Fig. 2, Fig. 4, Fig. 5, Fig. 6, Fig. 8～14 Depending on schematic diagram.

Figure 16 is to represent cuing open of the back light unit of mode different from the back light unit of Fig. 2, Fig. 4, Fig. 5, Fig. 6, Fig. 8～15 Depending on schematic diagram.

Figure 17 is the cross-sectional schematic representing conventional edge-lit backlight unit.

Description of reference numerals

1 portable terminal, very thin computer

2 operating portions

3 liquid crystal display parts

4 liquid crystal panels

5 liquid crystal display part shells

6 top boards

7 surface bearing components

8 connecting portions

9 operating portion shells

11 back light units

12 light guiding film

12a main body

12b prism portion

12c inclined plane

13 low profile light sources

14 first zones of reflections

15 second zones of reflections

16 reflector plates

17 optical sheets

18 reflecting layer

19 adhesive phases

20 reflecting layer

21 adhesive phases

31 extrusion molding apparatus

32 T-shaped moulds

33 compression rollers

33a compression roller

33b compression roller

41 back light units

42 first zones of reflections

43 reflecting layer

44 adhesive phases

51 back light units

52 light guiding film

53 first zones of reflections

54 second zones of reflections

55 back light units

56 light guiding film

57 first zones of reflections

58 light guiding film

58a main body

58b prism portion

61 back light units

62 light guiding film

63 first zones of reflections

64 second zones of reflections

65 back light units

66 light guiding film

67 first zones of reflections

71 back light units

72 light guiding film

73 first zones of reflections

74 second zones of reflections

75 back light units

76 light guiding film

77 first zones of reflections

78 light diffusion points

81 back light units

82 light guiding film

83 first zones of reflections

84 second zones of reflections

85 back light units

86 light guiding film

87 first zones of reflections

88 second zones of reflections

89 back light units

90 zones of reflections

91 back light units

92 light guiding film

93 first zones of reflections

94 second zones of reflections

95 light guiding film

96 prism portions

97 first zones of reflections

98 second zones of reflections

110 edge-lit backlight unit

111 light guide plates

112 optical sheets

115 reflector plates

116 top boards

117 light sources

X space

Specific embodiment

Hereinafter, while with reference to suitable accompanying drawing, embodiments of the present invention are described in detail.

[first embodiment]

＜ portable terminal ＞

The portable terminal 1 of Fig. 1 has operating portion 2 and liquid crystal display part 3, and described liquid crystal display part 3 is rotatably (can open Close) mode be connected with described operating portion 2.Described portable terminal 1, the composition of portable terminal 1 is partly integrally housed The thickness the thickest portion of liquid crystal display part 3 while closing () of housing (casing) be below 21mm, be ultrathin notebook PC (hereinafter referred to as " very thin computer 1 ").

The liquid crystal display part 3 of described very thin computer 1 have liquid crystal panel 4 and side-light type ultrathin back light unit (with Down also referred to as " back light unit "), described back light unit is from the back side laterally described liquid crystal panel 4 irradiation light.By the liquid crystal of housing Display part shell 5 keeps around the back side, side and the surface of described liquid crystal panel 4.Here, liquid crystal display part shell 5 Have：Top board 6, configuration is at the back side (and below) of liquid crystal panel 4；And, surface bearing component 7, configuration is in liquid crystal panel 4 The face side of the surrounding on surface.The housing of described very thin computer 1 has：Liquid crystal display part shell 5 and operating portion shell 9, described operating portion shell 9 is pivotally arranged at described liquid crystal display part shell 5 by connecting portion 8, built-in There is central processing unit (ultralow pressure CPU) etc..

As long as the average thickness as described liquid crystal display part 3 is not although the thickness of housing, in desired scope, just has There is special restriction, but, as the upper limit of the average thickness of liquid crystal display part 3, preferably 7mm, more preferably 6mm, Further preferably 5mm.On the other hand, as the lower limit of the average thickness of liquid crystal display part 3, preferably 2mm, more preferably Be 3mm it is further preferred that 4mm.If the average thickness of liquid crystal display part 3 exceedes the described upper limit, exist and cannot accord with Close the problem of the requirement of slimming of very thin computer 1.If additionally, the average thickness of liquid crystal display part 3 is less than described lower limit, Then there is to lead to intensity decreases, the luminance-reduction of liquid crystal display part 3.

＜ back light unit ＞

Possesses the back light unit 11 of Fig. 2 in the liquid crystal display part 3 of very thin computer 1.Back light unit 11 has：Light guiding film 12；One or more low profile light sources 13, to the end face irradiation light of light guiding film 12；First zone of reflections 14, to cover light guiding film 12 The mode of the face side of one or more low profile light source 13 side edge configures；Second zone of reflections 15, to cover the one of light guiding film 12 The mode of the rear side of individual or multiple low profile light source 13 side edge configures；Reflector plate 16, configuration is in the rear side of light guiding film 12；With And optical sheet 17, configuration is in the face side of light guiding film 12.Back light unit 11 makes the light projecting from one or more low profile light sources 13 Line substantially evenly projects from the surface of light guiding film 12.

(light guiding film)

Light guiding film 12 has main body 12a, and described main body 12a is formed as the plate that average thickness is less than more than 100 μm 600 μm Shape, light guiding film 12 is formed as less than more than 100 μm 600 μm as overall average thickness.Additionally, light guiding film 12 is formed as overlooking For general square shape.Light guiding film 12 is integrally formed as thickness substantially uniform lamellar (non-wedge-like).Light guiding film 12 also has Section is the prism portion 12b of triangle, and described prism portion 12b is got over the end edge surface being configured with one or more low profile light sources 13 The mode being more gradually increased near end edge side thickness is formed.In addition, " general square shape " except refer to completely square in addition to, for example Also following shapes are included：Two relative sides are with the tetragon of less than 10 ° of angle configurations；One or more of four corners Corner is the shape that have passed through chamfering；Four while one or more of while on the presence of sweep shape；Etc..This Outward, " ora terminalis of light guiding film " refers to the region at the surface of end face side comprising light guiding film and the back side, for example, refer to from light guiding film End face plays the 10mm area below on the end face direction relative with this end face.

Prism portion 12b from the surface of main body 12a to the height and position on the surface of low profile light source 13 or to low profile light source 13 The height and position on surface more than position formed.Prism portion 12b has towards oblique the inclining of inclination of low profile light source 13 lateral surface Inclined-plane 12c.Prism portion 12b is formed in the way of the end face of the end face of low profile light source 13 side and main body 12a becomes a face.Prism Portion 12b is formed in the way of one end of the long side direction of the ora terminalis of low profile light source 13 side from main body 12a to the other end.Additionally, Shape on the longitudinal section perpendicular to the end face relative with low profile light source 13 of prism portion 12b is uniform.

Preferably, prism portion 12b is formed by with main body 12a identical material.Moreover it is preferred that prism portion 12b with Main body 12a is integrally formed (that is, not passing through the others formable layer such as adhesive phase).Described back light unit 11, because rib Mirror portion 12b and main body 12a are integrally formed by identical material, it is possible to preventing from producing boundary between prism portion 12b and main body 12a Face, can make light to easily and reliably incide main body 12a from prism portion 12b.

As prism portion 12b bottom (boundary member with main body 12a) short side direction length (from low profile light source 13 side End to the end of another side length) (d) lower limit, preferably 2.5mm, more preferably 3mm, further preferably Be 4mm.On the other hand, as the upper limit of short side direction length (d) of prism portion 12b bottom, preferably 15mm, more preferably Be 10mm it is further preferred that 7mm.If described length (d) be less than described lower limit, exist inclined plane 12c with respect to The angle of inclination on the surface of main body 12a becomes too much and leads to be difficult to make to be laminated in the first reflector plate 14 of described inclined plane 12c The problem that the light of reflection is rightly propagated in light guiding film 12.If on the contrary, described length (d) exceedes the described upper limit, deposited Become big in the prism portion 12b forming region having main body 12a surface, thus the light that can not fully obtain main body 12a surface projects The problem in region.

Inclination angle (inclination angle of inclined plane 12c) as the prism portion 12b surface of the in-plane with respect to main body 12a (α) lower limit, preferably 10 °, more preferably 12 ° it is further preferred that 15 °.On the other hand, as with respect to main body The upper limit at the inclination angle (α) on the prism portion 12b surface of the in-plane of 12a, more preferably 40 °, enters one by preferably 45 ° Preferably 35 ° of step.If described inclination angle (α) is less than described lower limit, there are the prism portion 12b shape on main body 12a surface Region is become to become big, thus the light that can not fully obtain main body 12a surface projects the problem in region.If on the contrary, described incline (α) exceedes the described upper limit at oblique angle, then there is the light of the first reflector plate 14 reflection being difficult to make to be laminated in inclined plane 12c rightly The problem propagated in light guiding film 12.

As the lower limit of the average thickness of main body 12a, more preferably 150 μm it is further preferred that 200 μm.Another Aspect, as the upper limit of the average thickness of main body 12a, more preferably 500 μm it is further preferred that 400 μm.In main body In the case that the average thickness of 12a is less than described lower limit, there is a problem of that the intensity of light guiding film 12 becomes inadequate, additionally, there are The light that low profile light source 13 cannot be made fully incides the problem of light guiding film 12.On the contrary, the average thickness in main body 12a exceedes In the case of the described upper limit, exist and cannot use as the light guiding film of desired thin film in extra-thin portable terminal, Do not meet the problem of the requirement of the slimming of back light unit 11.

As the lower limit of necessary leaded light distance from the end face of low profile light source 13 side for the light guiding film 12, preferably 7cm, More preferably 9cm is it is further preferred that 11cm.On the other hand, the end face from low profile light source 13 side as light guiding film 12 The upper limit of the necessary leaded light distance rising, preferably 25cm, more preferably 23cm are it is further preferred that 22cm.Described Necessary leaded light distance less than described lower limit in the case of, exist and cannot use in the large-scale terminal beyond small mobile terminals Problem.On the contrary, in the case that described necessary leaded light distance exceedes the described upper limit, there are and as average thickness be Less than 600 μm of thin film light-guiding film easily produces warpage, can not obtain the problem of enough light conductivities in the case of using.Separately Outward, so-called " the necessary leaded light distance the end face from low profile light source 13 side of light guiding film 12 " refers to, penetrates from low profile light source 13 Go out and incide the light of the end face of light guiding film 12, the distance required for this end face is propagated to opposing end surface direction.Specifically come Say, for example, for unilateral edge-lit backlight unit, " necessity the end face from low profile light source 13 side of light guiding film 12 is led Electrical distance " refers to the distance from the end face of the low profile light source side of light guiding film to opposing end surface；For both sides edge-lit backlight unit For, " the necessary leaded light distance the end face from low profile light source 13 side of light guiding film 12 " refers to the end of the light source side from light guiding film Face is to the distance of central part.

As the lower limit of the surface area of light guiding film 12, preferably 150cm², more preferably 180cm², further preferably Be 200cm².On the other hand, as the upper limit of the surface area of light guiding film 12, preferably 760cm², more preferably 740cm²It is further preferred that 840cm².In the case that the surface area of light guiding film 12 is less than described lower limit, existing cannot be Problem used in large-scale terminal beyond small mobile terminals.On the contrary, the surface area in light guiding film 12 exceedes the described upper limit In the case of, there are in the case that the thin film light-guiding film as average thickness being less than 600 μm uses easily produce warpage, The problem of light conductivity can not fully be obtained.

Because light guiding film 12 must allow light pass through, thus using transparent, particularly water white synthetic resin as Main constituent is formed.Wherein, as the main constituent of light guiding film 12, preferably Merlon or acrylic resin, particularly preferred It is Merlon.Because polycarbonate transparent is excellent and refractive index is high, comprise Merlon by making light guiding film 12 As main constituent, it is susceptible to be totally reflected on the surface of light guiding film 12 and the back side, light can be made to have effect spread.Additionally, because Merlon has thermostability, so being difficult to deterioration that generation leads to etc. because of the heating of low profile light source 13.Further, because with Acrylic resin etc. is compared, and the water absorption of Merlon is little, so dimensional stability is high.Therefore, light guiding film 12 is by comprising to gather Carbonic ester, as main constituent, can suppress aging.On the other hand, because acrylic resin transparency is high, it is possible to reduce leading The loss of the light of light film 12.Light guiding film 12 preferably comprises the described main constituent of more than 80 mass %, more preferably comprises Described main constituents more than 90 mass % is it is further preferred that comprise more than 98% described main constituent.

As described Merlon, there is no particular limitation, can be in Linear polycarbonate or branched polycarbonate Any one or comprise Linear polycarbonate and the Merlon of branched polycarbonate both sides.

As Linear polycarbonate, there is the fragrant adoption carbon of the straight chain being fabricated by by known phosgenation or fusion method Acid esters, is made up of carbonate component and bisphenol component.As the precursor substance for importing carbonate component, for example, can arrange Lift：Phosgene, diphenyl carbonate etc..Additionally, as bis-phenol, such as can enumerate：2,2- double (4- hydroxy phenyl) propane, 2,2- Double (3,5- dimethyl -4- hydroxy phenyl) propane, 1,1-bis(4-hydroxyphenyl)-cyclohexane, 1,1- pair (3,5- dimesyl - 4- hydroxy phenyl) hexamethylene, double (4- hydroxy phenyl) decane of 1,1-, double (4- hydroxy phenyl) cyclodecane of 1,1-, double (the 4- hydroxyl of 1,1- Base phenyl) propane, double (3,5- dimethyl -4- hydroxy phenyl) cyclododecane of 1,1-, 4,4 '-dihydroxy diphenyl ether, 4,4 '-thio Biphenol, 4,4 '-dihydroxy -3,3- dichloro-diphenyl ether etc..These bisphenol components, can be used alone it is also possible to combine two kinds Used above.

The Merlon manufacturing as branched polycarbonate, useful branching agent, as branching agent, for example, can enumerate：Between Benzenetriol, trimellitic acid, 1,1,1- tri- (4- hydroxy phenyl) ethane, 1,1,2- tri- (4- hydroxy phenyl) ethane, 1,1,2- tri- (4- Hydroxy phenyl) propane, 1,1,1- tri- (4- hydroxy phenyl) methane, 1,1,1- tri- (4- hydroxy phenyl) propane, 1,1,1- tri- (2- first Base -4- hydroxy phenyl) methane, 1,1,1- tri- (2- methyl -4- hydroxy phenyl) ethane, 1,1,1- tri- (3- methyl -4- hydroxy benzeness Base) methane, 1,1,1- tri- (3- methyl -4- hydroxy phenyl) ethane, 1,1,1- tri- (3,5- dimethyl -4- hydroxy phenyl) methane, 1,1,1- tri- (3,5- dimethyl -4- hydroxy phenyl) ethane, 1,1,1- tri- (3- chloro-4-hydroxyl phenyl) methane, 1,1,1- tri- (3- Chloro-4-hydroxyl phenyl) ethane, 1,1,1- tri- (the chloro- 4- hydroxy phenyl of 3,5- bis-) methane, 1,1,1- tri- (3,5- bis- chloro-4-hydroxyl Phenyl) ethane, 1,1,1- tri- (3- bromo- 4- hydroxy phenyl) methane, 1,1,1- tri- (3- bromo- 4- hydroxy phenyl) ethane, 1,1,1- Three (the bromo- 4- hydroxy phenyl of 3,5- bis-) methane, 1,1,1- tri- (the bromo- 4- hydroxy phenyl of 3,5- bis-) ethane, 4,4 '-hydroxyl -2,5- Dihydroxydiphenyl ether etc..

As described acrylic resin, it is that have the resin coming from acrylic or methacrylic acid skeleton.As third The example of olefin(e) acid resin is although there is no particular limitation, but can enumerate：Polymethyl methacrylate etc. poly- (methyl) propylene Acid esters, methyl methacrylate-(methyl) acrylate copolymer, methyl methacrylate-(methyl) acrylic ester copolymer Thing, methyl methacrylate-acrylate-(methyl) acrylate copolymer, (methyl) acrylate-styrene are common Polymers, there is polymer (for example, methyl methacrylate-cyclohexyl methacrylate copolymer, the methyl of alicyclic alkyl Acrylic acid methyl ester .-(methyl) acrylic acid norborneol ester copolymer) etc..In these acrylic resins, preferably poly- (methyl) Acrylic acid methyl ester. etc. poly- (methyl) acrylic acid C1-6 Arrcostab, more preferably methyl methacrylate system resin.

In addition, light guiding film 12 can contain UV absorbent, incombustible agent, stabilizer, lubricant, processing aid, plasticising Agent, impact resistance auxiliary agent, phase contrast reduce agent, delustering agent, antibacterial, antifungus agent, antioxidant, releasing agent, antistatic additive etc. and appoint Meaning composition.

Preferably, light guiding film 12 overleaf has be made up of multiple recesses diffusion patterned.These multiple recesses are to dissipate Point-like is formed at the back side of light guiding film 12.Multiple recesses are projected to face side with making the uniform light from light guiding film 12 Mode configures.Specifically, multiple recesses with the position close to low profile light source 13 exist ratio few, with away from low profile light source 13 have the many modes of ratio change configures.Can by make the size of each recess identical and adjust allocation position adjust multiple recessed The presence ratio in portion it is also possible to adjust the presence ratio of multiple recesses by the size changing each recess.

As the shape of described recess, there is no particular limitation, can be hemispherical, coniform, cylindric, many pyramids Shape, polygonal column, shoes etc..Wherein, described recess is formed preferably as hemispherical concavity.By making described recess For hemispherical concavity, it is possible to increase mouldability, it is prevented from occurring edge and can promote slimming.

(first zone of reflections)

First zone of reflections 14 is shaped generally as rectangular long ribbon shape.First zone of reflections 14 is one or more slim to cover The mode of the face side of space X between light source 13 and light guiding film 12 configures.Additionally, first zone of reflections 14 with light guiding film 12 The parallel mode of end edge configures.Specifically, the ora terminalis of the side extending along long side direction of first zone of reflections 14, configures one The surface of individual or multiple low profile light source 13, and the ora terminalis side of the opposing party extending along long side direction, to cover prism portion 12b's The mode on surface configures.First zone of reflections 14 with one end of the long side direction of the ora terminalis of low profile light source 13 side from light guiding film 12 to The mode of the other end is formed.First zone of reflections 14 has flexibility.First zone of reflections 14, by having flexibility, can coordinate prism portion The curved edges bonding of the shape side such as surface of inclined plane 12c of 12b and low profile light source 13.In addition, " flexible " refers to, such as by width Degree 10cm, the test film of length 20cm are wrapped in along its length on the pole of diameter 5cm and are not produced brokenly with during visual observation Split, preferably refer to the test film of width 10cm, length 20cm be wrapped on the pole of diameter 3cm along its length and visual Rupture is not produced during observation.

Because first zone of reflections 14 is to cover the surface in the space between one or more low profile light sources 13 and light guiding film 12 The mode of side configures, thus described back light unit 11 can make from one or more low profile light sources 13 project and than to light guiding film The relative end face of 12 low profile light source 13 is more reflected and incides light guiding film by first zone of reflections 14 to the light of face side diffusion In 12.Additionally, because the refractive index of light guiding film 12 is than the sky being present between one or more low profile light sources 13 and light guiding film 12 The refractive index of the air of gap X is big, so described back light unit 11 can suppress the light being reflected by first zone of reflections 14 in light guiding film 12 and the interface of air be totally reflected, it is possible to increase to the incident efficiency of light guiding film 12 incidence.

Because light guiding film 12 has the prism portion 12b that section is triangle, described prism portion 12b is to be configured with one or many The mode that the end edge surface of individual low profile light source 13 is more gradually increased the closer to end edge side thickness is formed, so described back light unit 11 Can be increased by the area that described prism portion 12b makes the incident end face of the light of light guiding film 12, can make from low profile light source 13 The light projecting becomes easily to incide light guiding film.Additionally, because first zone of reflections 14 is to cover the side on the surface of prism portion 12b Formula configures, so the light that described back light unit 11 is prevented from inciding described prism portion 12b directly projects through prism portion To outside light guiding film 12.

In addition, first zone of reflections 14 covers the whole region of inclined plane 12c of prism portion 12b.According to such composition, institute Stating back light unit 11 can make to incide the light of prism portion 12b exactly to main body 12a from one or more low profile light sources 13 Incident.Additionally, first zone of reflections 14 be not covered with inclined plane 12c of prism portion 12b of light guiding film 12 beyond region (also It is the surface region of main body 12a).According to such composition, described back light unit 11 can make light easily from main body 12a Surface is substantially evenly projected.

First zone of reflections 14 has reflecting layer 18 and adhesive phase 19, and described adhesive layer 19 is layered in reflecting layer 18 The back side.First zone of reflections 14 is bonded with one or more low profile light sources 13 and light guiding film 12 by adhesive phase 19.Because first The zone of reflections 14 has the adhesive phase 19 being layered in reflecting layer 18, and by this adhesive phase 19 and one or more low profile light sources 13 and light guiding film 12 bond, so described back light unit 11 is prevented from light and leaks between first zone of reflections 14 and light guiding film 12 Go out, can further make the light projecting from low profile light source 13 rightly incide light guiding film 12.In addition, in present embodiment In, adhesive phase 19 is layered in the entire surface at the back side in reflecting layer 18, however, this adhesive phase 19 can also only be layered in On the adhesive surface of one or more low profile light sources 13 and light guiding film 12 bonding.

Reflecting layer 18 has：Matrix；With resin as main constituent；And Chinese white, it is contained in described matrix.Additionally, In reflecting layer 18, Chinese white is surrounded by matrix.Because reflecting layer 18 has：Matrix；With resin as main constituent；And white face Material, is contained in described matrix, so described back light unit 11 can make to project from low profile light source 13 and incide first zone of reflections 14 light diffuse-reflectance.Additionally, because reflecting layer 18 has：Matrix；With resin as main constituent；And Chinese white, it is contained in institute State in matrix, so easily formed at the back side in reflecting layer 18 resulting from multiple minute asperities of Chinese white, described backlight list Unit 11 can make to project from low profile light source 13 and occur to the light of first zone of reflections 14 incidence appropriate by described minute asperities Scattering.Therefore, described back light unit 11 can rightly adjust the light being reflected by first zone of reflections 14 and enters to light guiding film 12 The angle of incidence penetrated, it is possible to increase the light inciding in light guiding film 12 is propagated in light guiding film 12.

As the resin forming described matrix, there is no particular limitation, for example, can enumerate：Polyethylene terephthalate Ester, PEN, acrylic resin, Merlon, polystyrene, polyolefin, cellulose acetate, weatherability chlorine Ethylene etc..Wherein it is preferred that the polyethylene terephthalate of excellent heat resistance.

Additionally, as described Chinese white, there is no particular limitation, for example, can enumerate：Titanium oxide (titanium white), zinc oxide (flowers of zinc), ceruse (white lead), barium sulfate, Calcium Carbonate (Chalk) etc..

As the lower limit of the average thickness in reflecting layer 18, preferably 50 μm, more preferably 75 μm, further preferred It is 100 μm.On the other hand, as the upper limit of the average thickness in reflecting layer 18, preferably 300 μm, more preferably 275 μm, Further preferably 250 μm.In the case of average thickness in reflecting layer 18 is less than described lower limit, there is intensity becomes inadequate Problem.On the contrary, in the case that the average thickness in reflecting layer 18 exceedes the described upper limit, existing slim with portable terminal 1 The contrary problem of requirement changed.

As the lower limit of the mean diameter of described Chinese white, preferably 100nm, more preferably 200nm, further Preferably 300nm.On the other hand, as the upper limit of the mean diameter of described Chinese white, preferably 30 μm, more preferably It it is 20 μm it is further preferred that 10 μm.In the case that the mean diameter of described Chinese white is less than described lower limit, there are Reflexive reduces and is difficult to form the problem of suitable minute asperities at the back side in reflecting layer 18.On the contrary, in described white In the case that the mean diameter of pigment exceedes the described upper limit, there is a problem of that reflexive becomes uneven.In addition " mean diameter " Refer to：By the particle diameter from random 30 granules extracted out of the granule observing in the ultramicroscope of 1000 times of multiplying power averagely The meansigma methodss arriving, particle diameter is defined as Fei Leite footpath (clamping interval during projection image with the parallel lines of certain orientation).

As the lower limit of the content of described Chinese white, preferably 3 mass %, more preferably 5 mass %, further Preferably 7 mass %.On the other hand, as the upper limit of the content of described Chinese white, preferably 30 mass %, more preferably Be 25 mass % it is further preferred that 20 mass %.In the case that the content of described Chinese white is less than described lower limit, Presence cannot sufficient reflexive problem.On the contrary, in the case that the content of described Chinese white exceedes the described upper limit, There are dispersibility reduction, the intensity decreases in reflecting layer 18 of Chinese white.

In addition, UV absorbent, incombustible agent, stabilizer, lubricant, processing aid, increasing can also be contained in reflecting layer 18 Mould agent, impact resistance auxiliary agent, phase contrast reduction agent, delustering agent, antibacterial, antifungus agent, antioxidant, releasing agent, antistatic additive etc. Any condition.

As the binding agent for adhesive phase 19, there is no particular limitation, for example, can enumerate：Comprise vinyl acetate The aqueous binder of resin, synthetic rubber, polylactic acid, starch, acrylic resin etc. or emulsion binding agent；Comprise urea resin, Binding agent of the thermosetting resins such as melmac, phenol resin, epoxy resin, polyurethane resin etc..

The lower limit of the arithmetic mean roughness (Ra) as the back side in reflecting layer 18, preferably 1.5 μm, more preferably 1.7 μm it is further preferred that 2.0 μm.On the other hand, the arithmetic mean roughness as the back side in reflecting layer 18 (Ra) is upper Limit, preferably 4.0 μm, more preferably 3.8 μm it is further preferred that 3.5 μm.Reflecting layer 18 the back side count flat In the case that all roughness (Ra) is less than described lower limit, there is the light being reflected by first zone of reflections 14 and can not fully scatter, no The problem of the incident angle to light guiding film 12 incidence for the light being reflected by first zone of reflections 14 can fully be adjusted.On the contrary, anti- Penetrate the back side of layer 18 arithmetic mean roughness (Ra) exceed the described upper limit in the case of, exist and reflected by first zone of reflections 14 Light excessively scattering is thus be difficult to the problem of propagation in main body 12a of light guiding film 12.In addition, " arithmetic mean roughness (Ra) " is Refer to according to JIS-B0601-1994, cutoff λ c2.5mm, the value of evaluation length 12.5mm.

As the lower limit of 10 points of mean roughness (Rz) at the back side in reflecting layer 18, preferably 1.5 μm, more preferably 1.7 μm it is further preferred that 2.0 μm.On the other hand, as the back side in reflecting layer 18 10 points of mean roughness (Rz) upper Limit, preferably 40 μm, more preferably 35 μm it is further preferred that 30 μm.10 points of the back side in reflecting layer 18 average Roughness (Rz) be less than described lower limit in the case of, exist the light being reflected by first zone of reflections 14 can not fully scatter, can not Fully adjust the problem of the angle of incidence to light guiding film 12 incidence for the light being reflected by first zone of reflections 14.On the contrary, in reflecting layer In the case that 10 points of mean roughness (Rz) at 18 back side exceed the described upper limit, exist be difficult to adjustment anti-by first zone of reflections 14 The problem of the light penetrated.In addition, " 10 points of mean roughness (Rz) " is the value obtaining according to JIS-B0601-1994.

10 points of mean roughness (Rz) as the back side in reflecting layer 18 and the ratio (Rz/Ra) of arithmetic mean roughness (Ra) Lower limit, preferably 1.On the other hand, 10 points of mean roughness (Rz) as the back side in reflecting layer 18 are thick with arithmetic mean The upper limit of the ratio (Rz/Ra) of rugosity (Ra), preferably 20, more preferably 15 it is further preferred that 10.In reflecting layer 18 10 points of mean roughness (Rz) at the back side and the ratio (Rz/Ra) of arithmetic mean roughness (Ra) exceed the situation of the described upper limit Under, there is a problem of that the uneven of minute asperities becomes big, cannot get suitable scattered light.

Second zone of reflections 15 is shaped generally as rectangular long ribbon shape.Second zone of reflections 15 is one or more slim to cover The mode of the rear side of space X between light source 13 and light guiding film 12 configures.Additionally, second zone of reflections 15 be configured with one Or the parallel mode of end edge of the light guiding film 12 of multiple low profile light source 13 configures.Second zone of reflections 15 is with slim from light guiding film 12 The mode of one end to the other end of the long side direction of ora terminalis of light source 13 side is formed.Second zone of reflections 15 has flexibility.Second is anti- Penetrate the ora terminalis with 15 sides extending along long side direction to configure at the back side of one or more low profile light sources 13, and along long side The ora terminalis side of the opposing party that direction extends configures at the back side of main body 12a.Additionally, second zone of reflections 15 along long side direction extend The ora terminalis of the opposing party and first zone of reflections 14 along long side direction extend the opposing party ora terminalis overlook when be consistent.By This, described back light unit 11 can by the vertical view of light guiding film 12 when there is first zone of reflections 14 and the region of second zone of reflections 15 is made For reflector space, the light projecting from one or more low profile light sources 13 is reflected exactly, and can from by when overlooking not Light is substantially evenly projected in the injection region that there is the light of region composition of first zone of reflections 14 and second zone of reflections 15.But It is that, in described back light unit 11, the ora terminalis of the opposing party extending along long side direction of second zone of reflections 15 is it is also possible to compare first The ora terminalis of the opposing party extending along long side direction of the zone of reflections 14 is more to the inner side (end relative with one or more low profile light sources 13 The end face side of the opposite side in face) extend.According to such composition, light easily the penetrating from light reflected by second zone of reflections 15 Go out region to project.

Described back light unit 11, because having second zone of reflections 15, it is possible to make from one or more low profile light sources 13 Project and compare to the relative end face of the low profile light source 13 with light guiding film 12 more support or oppose surface side diffusion light by second zone of reflections 15 Reflect and incide in light guiding film 12.Additionally, this back light unit 11, because the refractive index ratio of light guiding film 12 is present in one or many The refractive index of the air of space X between individual low profile light source 13 and light guiding film 12 is big, it is possible to suppression is by second zone of reflections 15 The light of reflection is totally reflected at the interface of light guiding film 12 and air, it is possible to increase to the incident efficiency of light guiding film 12 incidence.Special It is not, because described back light unit 11, except having first zone of reflections 14, also has second zone of reflections 15, it is possible to further To easily and reliably prevent space X between one or more low profile light sources 13 and light guiding film 12 for the light from spilling.

Second zone of reflections 15 has reflecting layer 20 and adhesive phase 21, and described adhesive layer 21 is layered in reflecting layer 20 Surface.Second zone of reflections 15 is bonded with one or more low profile light sources 13 and light guiding film 12 by adhesive phase 21.Because second The zone of reflections 15 is bonded with one or more low profile light sources 13 and light guiding film 12 by adhesive phase 21, so described back light unit 11 It is prevented from light to spill between second zone of reflections 15 and light guiding film 12, can more reliably make from low profile light source 13 injection Light rightly incides in light guiding film 12.

As the reflecting layer 20 of second zone of reflections 15, can have the reflecting layer 18 identical structure with first zone of reflections 14 Become.Additionally, as the adhesive phase 21 of second zone of reflections 15, can have adhesive phase 19 identical with first zone of reflections 14 Constitute.Additionally, the arithmetic mean roughness (Ra) on surface as reflecting layer 20,10 points of mean roughness (Rz) and 10 points Mean roughness (Rz) and the ratio (Rz/Ra) of arithmetic mean roughness (Ra), can be with the reflecting layer 18 of first zone of reflections 14 The back side is identical.

(low profile light source)

One or more low profile light sources 13 are configured in the way of relative with one or more end faces of light guiding film 12, in this reality Apply in mode, configured in the way of relative with the 1 of light guiding film 12 end face.The outgoing plane of low profile light source 13 with light guiding film 12 The relative mode of end face configures.The low profile light source of the prism portion 12b of the height and position on the surface of low profile light source 13 and light guiding film 12 The end height position of 13 sides is equal or below it, the height and position at the back side of low profile light source 13 and the back side of light guiding film 12 Height and position is equal.As low profile light source 13, it is possible to use various low profile light sources, for example, can enumerate thin-type LED element.This Outward, as described thin-type LED element, for example, there is one or more light emitting diodes (LED) and the housing surrounding this LED. In addition, " low profile light source " refers to, such as average height is the light source of below 1mm, and preferably effectively outgoing plane (for example surrounds light The peristome of the housing in source) average height be below 1.5mm light source, the average height of more preferably effectively outgoing plane is Less than 800 μm of light source is it is further preferred that the average height of effective outgoing plane is less than 600 μm of light source.

The end face of low profile light source 13 and the light guiding film 12 relative with this low profile light source 13 separates.Low profile light source 13 and light guiding film The lower limit of 12 equispaced, preferably 30 μm, more preferably 50 μm.On the other hand, low profile light source 13 and light guiding film 12 The equispaced of end face the upper limit, preferably 2mm, more preferably 1mm.If low profile light source 13 is flat with light guiding film 12 All interval is less than described lower limit, then the light projecting and being reflected by first zone of reflections 14 or second zone of reflections 15 from low profile light source 13 Incident angle to light guiding film 12 incidence easily diminishes, and there is the light being reflected by first zone of reflections 14 or second zone of reflections 15 difficult To incide the problem in light guiding film 12.If on the contrary, low profile light source 13 is exceeded on described with the equispaced of light guiding film 12 Limit, then have that back light unit 11 unnecessarily becomes big, and there is a problem of that reflection loss increases.

(reflector plate)

The light that the rear side from light guiding film 12 for the reflector plate 16 projects is to surface lateral reflection.As reflector plate 16, permissible Enumerate：The white tablets containing filler are disperseed in the substrate resins such as polyester based resin；By being formed by polyester based resin etc. The metals such as the surface AM aluminum metallization of film, silver and improve minute surface piece of normal reflection etc..

(optical sheet)

Optical sheet 17 has to optical functions such as the light diffusion incident from rear side, refractions.As optical sheet 17, for example Can enumerate：There is the light diffusing sheet of light diffusion function；There is the prism of the reflective functions reflecting light to normal direction side Piece etc..

＜ manufacture method ＞

(manufacture method of light guiding film)

Then, the manufacture method of light guiding film 12 is illustrated.Light guiding film 12 for example passes through extrusion moulding molding.

Manufacture method as the situation being manufactured light guiding film 12 by extrusion moulding is had：Make the operation (step of film molding Rapid 1)；Overleaf form diffusion patterned operation (step 2)；And form the operation of prism portion 12b on surface.Using Fig. 3's Extrusion molding apparatus 31 carry out step 1 to step 3 simultaneously.In addition, not forming diffusion patterned situation at the back side of light guiding film 12 Under, omit step 2.

Extrusion molding apparatus 31 have：Extruder and T-shaped mould 32, a pair of compression roller 33 and devices for taking-up (the non-table of in figure Show) etc..As T-shaped mould 32, for example, can use the well-known mould such as fish tail mould, difference pipe die, rack-style mould.Squeeze for a pair Pressure roller 33 is configured in the way of adjacent and parallel.Extruder and T-shaped mould 32 can will melt tree in the crack of a pair of compression roller 33 Fat extrudes slabbing.A pair of compression roller 33 is provided with temperature control equipment, can be to be best suitable for being extruded into by surface temperature control The temperature of type.As compression roller 33, it is preferred to use covered the gold that the flexible roller of elastomer is constituted by metallic roll and surface Belong to resilient roller.

The compression roller 33a of a pair of compression roller 33 and compression roller 33b relative configuration.Wherein, compression roller 33a turns as on surface Print diffusion patterned roller mould to be formed.Additionally, being formed with recess corresponding with prism portion 12b on the surface of compression roller 33b.

Step 1 is carried out by following methods of forming that melt extrudes：By the formation material of the light guiding film 12 of molten condition to T-shaped Mould 32 supplies, and by this formation material after extruder and T-shaped mould 32 are extruded, is extruded by a pair of compression roller 33.In addition, Fusing point of used resin etc. can be considered, suitably select the melting of the formation material of light guiding film 12 from T-shaped mould 32 extrusion Temperature.To adjust the average thickness of light guiding film 12 by adjusting configuration space of a pair of compression roller 33 etc..

The diffusion patterned of the surface of compression roller 33a will be transferred in, in the formation material solidification of the light guiding film 12 of molten condition Before transferred, thus carry out step 2.In step 2, by the light guiding film 12 with a pair of compression roller 33 extrusion molten state Form material, the diffusion patterned back side being transferred to light guiding film 12 on compression roller 33a surface will be transferred in.In step 2, by institute State transfer, formed at the back side of light guiding film 12 diffusion patterned.

Step 3 and step 2 are carried out simultaneously.The formation material of the light guiding film 12 of molten condition enters and is formed at compression roller 33b Surface recess, and then make the formation material solidification of light guiding film 12 when maintaining the state entering, thus carry out step 3.

In addition, step 1, step 2 and step 3, can carry out it is also possible to carry out offline as described above online.

(manufacture method of the zone of reflections)

As the manufacture method of first zone of reflections 14 and second zone of reflections 15, for example, have：To comprise to form resin-made base The formation material in the reflecting layer 18,20 of the synthetic resin of body and Chinese white, after extruder and T-shaped mould are extruded, to specify Stretching ratio stretching operation (step 11)；By coating, adhesive phase 19,21 is laminated in squeezing by step 11 molding Go out the operation (step 12) on a face of body；And the duplexer being formed by step 12 is cut to the operation of given size (step 13).

Additionally, in the manufacture of first zone of reflections 14 and second zone of reflections 15, it is possible to have overleaf implement unglazed place The operation of reason, for forming suitable minute asperities,.

＜ advantage ＞

Typically, since the just diffusion light projecting from light sources such as LED, so in edge-lit backlight unit, penetrating from light source A part for the light going out does not impinge on the end face of light guiding film or does not rightly propagate in light guiding film, thus losing.This Outward, more promote the filming of light guiding film, the loss of such light becomes more notable.On the other hand, because described side-light backlight Unit 11 possesses first zone of reflections 14, and described first zone of reflections 14 is to cover one or more low profile light sources 13 side of light guiding film 12 The mode of the face side of ora terminalis configures, it is possible to make from one or more low profile light sources 13 project light by first zone of reflections 14 reflections, and the light after can making to be reflected by this first zone of reflections 14 incides in light guiding film 12.Therefore, even if in leaded light In the case of the average thickness of film 12 is less than more than 100 μm 600 μm less, described edge-lit backlight unit 11 also can make The light irradiating from one or more low profile light sources 13 rightly incides in light guiding film 12, and the utilization thus, it is possible to improve light is imitated Rate, can promote the raising of brightness.

Described reflection band member (first zone of reflections 14 and second zone of reflections 15) can make the light projecting from low profile light source 13 Line rightly incides in light guiding film 12.

Described portable terminal 1, because possessing described back light unit 11, it is possible to make from one or more low profile light sources The light of 13 irradiations rightly incides in light guiding film 12, thus, it is possible to improve the utilization ratio of light, can promote carrying of brightness High.

[second embodiment]

With reference to Fig. 2, the back light unit of second embodiment of the present invention is illustrated.Except for first zone of reflections 14 Adhesive phase 19 different with the binding agent of the adhesive phase 21 of second zone of reflections 15 beyond, second embodiment of the present invention Back light unit has identical composition with the back light unit 11 of Fig. 2.As first zone of reflections 14 for described back light unit The binding agent of the adhesive phase 21 of adhesive phase 19 and second zone of reflections 15, it is possible to use can be by first zone of reflections 14 and second The binding agent that the zone of reflections 15 is bonded with false tacky state with one or more low profile light sources 13 and light guiding film 12.As such viscous Mixture, for example, can enumerate acrylic resin, methacrylic resin, methacrylic resin, butyl rubber, silicones etc. As the pressure sensitive binding agent for principal polymeric.

＜ advantage ＞

Because first zone of reflections 14 and second zone of reflections 15 with false tacky state and one or more low profile light sources 13 and are led Light film 12 bonds, so described back light unit is prevented from light from first zone of reflections 14 and second zone of reflections 15 and light guiding film 12 Between spill, and can easily configure and re-paste first zone of reflections 14 and second zone of reflections 15.

[the 3rd embodiment]

The liquid crystal display part 3 of very thin computer 1 possesses the back light unit 41 of Fig. 4.Back light unit 41 has：Light guiding film 12； One or more low profile light sources 13, as the light source of the end face irradiation light to light guiding film 12；And first zone of reflections 42, to cover The mode of the face side of one or more low profile light sources 13 side edge of light guiding film 12 configures.Additionally, back light unit 41 is except leading Outside light film 12, one or more low profile light source 13 and first zone of reflections 42, can also have configuration at the back side of light guiding film 12 The reflector plate of side and configuration are in the optical sheet of face side etc. of light guiding film 12.Back light unit 41 makes from one or more slim The light that light source 13 projects substantially evenly projects from the surface of light guiding film 12.The light guiding film 12 of back light unit 41 and low profile light source 13, due to identical with the back light unit 11 of Fig. 2, so giving identical reference and omitting the description.

First zone of reflections 42 has reflecting layer 43 and adhesive phase 44, and described adhesive layer 44 is layered in the back of the body in reflecting layer 43 Face.First zone of reflections 42 is bonded with by way of covering prism portion 12b surface by adhesive phase 44.In addition, in present embodiment In, the first zone of reflections 42 configuration region overlapping with prism portion 12b when overlooking.In addition to the position difference of configuration, the One zone of reflections 42 has identical composition with first zone of reflections 14 of Fig. 2.

＜ advantage ＞

This back light unit 41 can make the light projecting from low profile light source 13 rightly incide in light guiding film 12, thus, it is possible to Enough improve the utilization ratio of light, the raising of brightness can be promoted.This back light unit 41, makes light guiding film 12 by prism portion 12b The area of the incident end face of light increases, and the light irradiating from low profile light source 13 can be made easily to incide light guiding film 12, and Because first zone of reflections 42 is configured in the way of covering prism portion 12b surface, it is possible to preventing from inciding this prism portion 12b's Light directly injects to outside light guiding film 12 through prism portion 12b.

[other embodiment]

In addition, in addition to described embodiment, the edge-lit backlight unit of the present invention and reflection band member can be to enter Gone various modifications, improvement mode implement.For example, described back light unit need not necessarily have reflector plate and optical sheet.Additionally, Described back light unit need not necessarily have first zone of reflections and second zone of reflections it is also possible to only have first zone of reflections.Additionally, i.e. Make in the case that there is first zone of reflections and second zone of reflections, the composition of first zone of reflections and second zone of reflections can not also Same, can also be for example that any one party in only first zone of reflections and second zone of reflections can bond in vacation.Additionally, described leaded light Film need not necessarily have prism portion it is also possible to be only made up of the main body for the tabular of general square shape when being formed as overlooking.Additionally, institute State the section in prism portion without must be triangle.The cross sectional shape in described prism portion, can also be for example by with main body Border is trapezoidal as go to the bottom, or has continuous and extend to one or more low profile light source sides for the region of triangle with section Section be rectangular segment shape, etc..

The reflecting layer of described first zone of reflections and/or second zone of reflections is without necessarily having matrix and be contained in described base Chinese white in body, such as this reflecting layer can also be made up of metal forming, metallic plate etc..Additionally, described first zone of reflections and/ Or second the zone of reflections for example can also have：Substrate layer, is formed by white synthetic resin；And light scattering layer, it is layered in described Inner face (face with the low profile light source opposite side) stacking of substrate layer, the binding agent comprising filler and coating this filler.Described First zone of reflections and/or second zone of reflections have in the case that such composition has, and the light being reflected by substrate layer can be made to pass through Light scattering layer scatters.Therefore, it is possible to rightly adjust by the light of described first zone of reflections and/or the reflection of second zone of reflections to leaded light The incident angle of incidence of film, it is possible to increase incident light is propagated in light guiding film into light guiding film.Described first zone of reflections and/ Or second the zone of reflections without certain with one end of the long side direction of the ora terminalis of the low profile light source side from light guiding film to the other end Mode is formed, for example, can configure described first zone of reflections and/or second zone of reflections in the allocation position of each low profile light source.

Additionally, illustrating the composition with forming prism portion with main body identical material in the embodiment shown, but Described prism portion can also be formed with the material different from main body.So, forming prism portion with the material different from main body In the case of, as the main constituent forming prism portion, for example, can enumerate active energy ray-curable resin, thermosetting resin etc.. Wherein, as the main constituent forming prism portion, preferably ultraviolet curing resin.By as the main one-tenth forming prism portion Divide and use ultraviolet curing resin, it is possible to increase the mouldability of the coating in prism portion.

As described ultraviolet curing resin, can enumerate：Urethane acrylate system resin, polyester acrylate system Resin, epoxy acrylate system resin, polyalcohol acrylate system resin, epoxy resin etc., wherein it is preferred that acrylate It is resin, particularly preferably polyfunctional acrylic ester.

As described polyfunctional acrylic ester, for example, can enumerate：Pentaerythritol acrylate, dipentaerythritol acrylic acid Ester, tetramethylolmethane methacrylate, dipentaerythritol methacrylate etc..In addition, so-called " polyfunctional acrylic ester " Refer to the compound in molecule with plural acryloxy or methacryloxy.

As polyfunctional acrylate monomer, for example, can enumerate：Ethylene glycol diacrylate, diethylene glycol diacrylate Ester, 1,6 hexanediol diacrylate, neopentylglycol diacrylate, trimethylolpropane trimethacrylate, trihydroxy methyl second Alkane triacrylate, tetramethylol methane triacrylate, tetramethylol methane tetraacrylate, trimethylolethane trimethacrylate propylene Acid esters, pentaerythritol diacrylate, pentaerythritol triacrylate, tetramethylol methane tetraacrylate, glycerol tri-acrylate, Dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, Dipentaerythritol Pentaacrylate, dipentaerythritol 6 third Olefin(e) acid ester, three (acryloyl-oxyethyl) isocyanuric acid ester, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate Ester, 1,6-HD dimethylacrylate, neopentylglycol dimethacrylate, trimethylol propane trimethyl acrylic acid Ester, trimethylolethane trimethacrylate methacrylate, tetramethylol methane trimethyl acrylic ester, tetramethylol methane tetramethyl third Olefin(e) acid ester, trimethylolethane trimethacrylate methacrylate, dimethyl pentaerythritol acrylate, the acid of tetramethylolmethane trimethacrylate Ester, pentaerythritol tetramethylacrylate, glycerol trimethacrylate, dipentaerythritol trimethyl acrylic ester, two seasons penta Tetrol tetramethyl acrylate, dipentaerythritol pentamethacrylates, dipentaerythritol hexamethacrylate, acrylic acid are different Norbornene ester etc..These compounds may be used singly or in combination of two or more.In addition it is also possible to be described monomer Dimer, the oligomer such as trimer.

Additionally, as the formation material in prism portion, in order to promote the solidification of ultraviolet curing resin, preferably comprising Light trigger.

As described light trigger, for example, can enumerate：1-Phenylethanone., benzophenone, dihydroxy benaophenonel, Michler's keton, α- Amyl group oxime ester, thiaxanthone and their derivant etc..

As with respect to described ultraviolet curing resin 100 mass parts, described light trigger content, for example permissible It is below more than 0.01 mass parts 20 mass parts.

In addition, prism portion can also contain：UV absorbent, incombustible agent, stabilizer, lubricant, processing aid, plasticising Agent, impact resistance auxiliary agent, phase contrast reduce agent, delustering agent, antibacterial, antifungus agent, antioxidant, releasing agent, antistatic additive etc. and appoint Meaning composition.

In the case that main body and prism portion are formed by different materials, as the refractive index (n of main body₁) and prism portion Refractive index (n₂) difference lower limit, preferably 0.05, more preferably 0.07 it is further preferred that 0.09.On the other hand, Refractive index (n as main body₁) and prism portion refractive index (n₂) difference the upper limit, preferably 0.15, more preferably 0.13 it is further preferred that 0.11.By making the refractive index (n of main body₁) and prism portion refractive index (n₂) difference in described model In enclosing, the light of the first reflector plate reflection being laminated in inclined plane can be made suitably to support or oppose at the interface in prism portion and main body Surface side reflects.Region thereby, it is possible to make this light project the low profile light source side region from the light of body surfaces is rightly penetrated Go out, it is possible to increase the homogenization of brightness.

In addition, main body as the light guiding film and prism portion system of the different light guiding film being formed in the case that material is formed Make method, for example, can enumerate：Prism portion forms the method that material is coated with to body surfaces.

Light guiding film for described back light unit can also have wavy small modulated structure on the surface of main body.Have The composition of such small modulated structure is as shown in Figure 5.The back light unit 51 of Fig. 5 has：Light guiding film 52；One or more slim Light source 13, to the end face irradiation light of light guiding film 52；First zone of reflections 53, with parallel with the end edge of light guiding film 52 and cover one or The mode of the face side in space between multiple low profile light sources 13 and light guiding film 52 configures；Second zone of reflections 54, be configured with The end edge of the light guiding film 52 of one or more low profile light sources 13 is parallel and covers one or more low profile light sources 13 and light guiding film 52 Between the mode of the rear side in space configure；Reflector plate (diagram is omitted), configuration is in the rear side of light guiding film 52；And optics Piece (diagram is omitted), configuration is in the face side of light guiding film 52.The back light unit of Fig. 5, except the surface of the main body in light guiding film 52 Have beyond wavy small modulated structure, there is the back light unit 11 identical composition with Fig. 2.

The end face that the ridge line direction of described wavy small modulated structure is relative with the low profile light source 13 of light guiding film 52 is put down Row configuration.Thus, with respect to the direct of travel of the light propagated in light guiding film 52, the ridge line direction position of small modulated structure In substantially vertical position, therefore result from and become to the incident angle of incidence in surface due to the light that small modulated structure causes Dynamic, it is possible to increase to go out photosensitiveness from what light guiding film 52 surface went out light.Additionally, as under the ridge line interval p of small modulated structure Limit, preferably 1mm, more preferably 10mm are it is further preferred that 20mm.On the other hand, as small modulated structure Ridge line is spaced the upper limit of p, and preferably 500mm, more preferably 100mm are it is further preferred that 60mm.Between ridge line In the case that p is less than described lower limit, there is a problem of that light projects from the excessive surface of light guiding film 52.On the other hand, on mountain Crestal line interval p exceed the described upper limit in the case of, there is a problem of light guiding film 52 go out photosensitiveness raising effect low.In addition, it is excellent Choosing be all of ridge line interval p of small modulated structure all in described scope, but multiple mountains of small modulated structure The part that crestal line is spaced in p can also be outside described scope, in such a case, it is possible to be in multiple ridge line intervals More than 50% in described scope, and preferably 70% ridge line is spaced in described scope.

Additionally, as the ridge line on the basis of the approximately virtual face that multiple valley routes of described small modulated structure pass through Average height h lower limit, preferably 5 μm, more preferably 7 μm it is further preferred that 9 μm.On the other hand, with described The upper limit of average height h of ridge line on the basis of the approximately virtual face that multiple valley routes of small modulated structure pass through, preferably Be 40 μm, more preferably 20 μm it is further preferred that 15 μm.It is less than the situation of described lower limit in described average height h Under, there is a problem of light guiding film 52 go out photosensitiveness raising effect low.On the contrary, exceeding the described upper limit in described average height h In the case of, there is a problem of that light projects from the excessive surface of light guiding film 52.

In addition, the ridge line direction of described wavy small modulated structure can also be with low profile light source 13 phase of light guiding film 52 To end face substantially vertical.Thus, the light propagated in light guiding film 52 when surface reflect, the traveling side of a part of light To deflection ridge line side, therefore light is easily to ridge line direction side optically focused.Additionally, in addition, because project from surface Light passes through the refraction in wavy described small modulated structure, spreads slightly to the direction vertical with ridge line direction, so Irradiant diffusibility is improved.Additionally, the ridge line direction as described wavy small modulated structure like this In the case that the end face relative with the low profile light source 13 of light guiding film 52 is substantially vertical, small modulated structure ridge line is spaced p And average height h of the ridge line on the basis of the approximately virtual face that multiple valley routes pass through, can be with small modulated structure The ridge line direction end face configured in parallel relative with the low profile light source 13 of light guiding film 52 when situation identical.

In addition, in the case that light guiding film 52 is formed by extrusion moulding, can be by using specific sectional shape Lip open mold is forming described small modulated structure.Specifically, by using the cross sectional shape of described lip opening can be Along the mould of the reversion shape of small modulated structure, at least one surface side of light guiding film 52, the rugose small modulation of shape Structure.

Additionally, the surface as the main body in light guiding film has the back light unit of wavy small modulated structure, such as The back light unit 55 shown in Fig. 6 can be enumerated.The back light unit 55 of Fig. 6 has：The light guiding film 56 being only made up of main body；One or Multiple low profile light sources 13, the one or more end face relative configurations with light guiding film 56；And first zone of reflections 57, to cover one Or the mode of the face side in space between multiple low profile light source 13 and light guiding film 56 configures.This back light unit 55 described wavy The ridge line direction of the small modulated structure end face configured in parallel relative with the low profile light source 13 of light guiding film 56.Additionally, first The zone of reflections 57 has：Matrix, with resin as main constituent；And Chinese white, it is contained in described matrix.

Additionally, as the light guiding film in body surfaces with wavy small modulated structure, such as Fig. 7 institute can also be enumerated The light guiding film 58 shown.It is the prism portion 58b, described prism portion 58b of triangle that the light guiding film 58 of Fig. 7 has main body 58a and section Formed by the material different from main body 58a, to be configured with the end edge surface of one or more low profile light sources the closer to end edge side thickness Spend the mode being more gradually increased to be formed, in surface configuration first zone of reflections 59 of described prism portion 58b.

Additionally, as the light guiding film of described back light unit, one or more low profile light source, first zone of reflections and the second reflection The composition of band, for example can also be using the composition described in Fig. 8 to Figure 14.

The back light unit 61 of Fig. 8 has：Light guiding film 62；One or more low profile light sources 13, shine to the end face of light guiding film 62 Penetrate light；First zone of reflections 63, with and covering one or more low profile light sources 13 parallel with the end edge of light guiding film 62 and light guiding film 62 Between the mode of the face side in space configure；And second zone of reflections 64, be configured with one or more low profile light sources 13 Light guiding film 62 end edge parallel and cover the rear side in space between one or more low profile light sources 13 and light guiding film 62 Mode configures.Light guiding film 62 is only made up of main body, the height and position on the height and position of this body surfaces and low profile light source 13 surface Roughly equal, and the rear-side height position of the height and position at the back side of this main body and low profile light source 13 is roughly equal.The described back of the body Even if light unit 61 has such composition it is also possible to make the light from the injection of one or more low profile light sources 13 rightly incident The raising of brightness in light guiding film 62, thus, it is possible to improve the utilization ratio of light, can be promoted.

The back light unit 71 of Fig. 9 has：Light guiding film 72；One or more low profile light sources 13, shine to the end face of light guiding film 72 Penetrate light；First zone of reflections 73, with and covering one or more low profile light sources 13 parallel with the end edge of light guiding film 72 and light guiding film 72 Between the mode of the face side in space configure；And second zone of reflections 74, be configured with one or more low profile light sources 13 Light guiding film 72 end edge parallel and cover the rear side in space between one or more low profile light sources 13 and light guiding film 72 Mode configures.Light guiding film 72 is only made up of main body, and the end face relative with one or more low profile light sources 13 from face side to Back side laterally outside tilts.This back light unit 71, by having such composition, can make the incident end of the light of light guiding film 72 The area in face increases, and the light projecting from one or more low profile light sources 13 can be made more effectively to incide in light guiding film 72, The raising of brightness thus, it is possible to improve the utilization ratio of light, can be promoted.

The back light unit 81 of Figure 10 has：Light guiding film 82；One or more low profile light sources 13, shine to the end face of light guiding film 82 Penetrate light；First zone of reflections 83, with and covering one or more low profile light sources 13 parallel with the end edge of light guiding film 82 and light guiding film 82 Between the mode of the face side in space configure；And second zone of reflections 84, be configured with one or more low profile light sources 13 Light guiding film 82 end edge parallel and cover the rear side in space between one or more low profile light sources 13 and light guiding film 82 Mode configures.The light guiding film 82 of this back light unit 81 is only made up of main body, and the surface of one or more low profile light source 13 Height and position is higher than the height and position on light guiding film 82 surface.Generally, in the back light unit of this composition, from one or more slim The light that light source projects, is not incident on light guiding film but easily relative with low profile light source than to light guiding film end face is more to surface Side is spread.On the other hand, this back light unit 81 because having first zone of reflections 83 and second zone of reflections 84, it is possible to make from The light that one or more low profile light sources 13 project more effectively incides in light guiding film 82, and the utilization thus, it is possible to improve light is imitated Rate, can promote the raising of brightness.

The back light unit 91 of Figure 11 has：Light guiding film 92；One or more low profile light sources 13, shine to the end face of light guiding film 92 Penetrate light；First zone of reflections 93, with and covering one or more low profile light sources 13 parallel with the end edge of light guiding film 92 and light guiding film 92 Between the mode of the face side in space configure；And second zone of reflections 94, be configured with one or more low profile light sources 13 Light guiding film 92 end edge parallel and cover the rear side in space between one or more low profile light sources 13 and light guiding film 92 Mode configures.The light guiding film 92 of this back light unit 91 is only made up of main body, and the surface of one or more low profile light source 13 The height and position on the surface than light guiding film 92 for the height and position is high, and the height and position at the back side of one or more low profile light source 13 Lower than the rear-side height position of light guiding film 92.Generally, in such back light unit constituting, penetrate from one or more low profile light sources The light going out, be not incident on light guiding film but easily than to the end face relative with the low profile light source of light guiding film more to face side or the back of the body Surface side is spread.On the other hand, this back light unit 91, because have first zone of reflections 93 and second zone of reflections 94, it is possible to making The light projecting from one or more low profile light sources 13 more effectively incides in light guiding film 92, thus, it is possible to improve the utilization of light Efficiency, can promote the raising of brightness.

The back light unit 65 of Figure 12 has：Light guiding film 66；One or more low profile light sources 13, shine to the end face of light guiding film 66 Penetrate light；And first zone of reflections 67, with parallel with the end edge of light guiding film 66 and cover one or more low profile light sources 13 with guide-lighting The mode of the face side in the space between film 66 configures.Light guiding film 66 is only made up of main body, and one or more low profile light source The height and position on 13 surface is higher than the height and position on light guiding film 66 surface.First zone of reflections 67 has：Matrix, based on resin Composition；And Chinese white, it is contained in described matrix.Additionally, being formed between first zone of reflections 67 and the surface of light guiding film 66 There is hollow region.

As the vertical dimension (d from the surface of light guiding film 66 to the surface of one or more low profile light sources 13₃) with from thin In-plane distance (the d of the bonding part of type light source 13 to the first zone of reflections 67 and light guiding film 66₂) ratio (d₃/d₂) lower limit, excellent Choosing is 1/5, and more preferably 3/10 it is further preferred that 2/5.On the other hand, from the surface of light guiding film 66 to or Vertical dimension (the d on multiple low profile light source 13 surfaces₃) and the bonding from low profile light source 13 to the first zone of reflections 67 and light guiding film 66 In-plane distance (the d in portion₂) ratio (d₃/d₂) the upper limit, preferably 1, more preferably 9/10 it is further preferred that 4/5.In described distance than (d₃/d₂) less than in the case of described lower limit, the plane being covered by first zone of reflections 67 of light guiding film 66 Region becomes big, there is the output optical zone domain that can not fully obtain light guiding film 66 surface.On the contrary, in described distance than (d₃/ d₂) exceed the described upper limit in the case of, there is the light being reflected by first zone of reflections 67 and can not rightly incide in light guiding film 66 Problem.

Even if this back light unit 65 has such composition it is also possible to make the light projecting from one or more low profile light sources 13 Line rightly incides the raising that thus, it is possible to improve the utilization ratio of light, can promote brightness in light guiding film 66.Additionally, should Back light unit 65, because being formed as hollow region between the back side of light guiding film 66 surface and first zone of reflections 67, so while The refractive index of light guiding film 66 bigger than the refractive index of air it is thus possible to make light easily incide light guiding film 66 from hollow region Interior.

The back light unit 75 of Figure 13 has：Light guiding film 76；One or more low profile light sources 13, shine to the end face of light guiding film 76 Penetrate light；And first zone of reflections 77, with parallel with the end edge of light guiding film 76 and cover one or more low profile light sources 13 with guide-lighting The mode of the face side in the space between film 76 configures.Light guiding film 76 is only made up of main body, and one or more low profile light source The height and position on the surface than light guiding film 76 for the height and position on 13 surface is high.First zone of reflections 77 overleaf has multiple light and expands Scatterplot 78.Additionally, being formed with hollow region between first zone of reflections 77 and the surface of light guiding film 76.Even if this back light unit 75 There is such composition it is also possible to make the light projecting from one or more low profile light sources 13 rightly incide light guiding film 76 Interior, the raising of brightness thus, it is possible to improve the utilization ratio of light, can be promoted.Additionally, this back light unit 75, due to light guiding film 76 Surface and the back side of first zone of reflections 77 between formed as hollow region, so while the refractive index of light guiding film 76 compares air Refractive index big it is thus possible to make light easily incide in light guiding film 76 from hollow region.

The back light unit 85 of Figure 14 has：Light guiding film 86；One or more low profile light sources 13, shine to the end face of light guiding film 86 Penetrate light；And first zone of reflections 87, with parallel with the end edge of light guiding film 86 and cover one or more low profile light sources 13 with guide-lighting The mode of the face side in the space between film 86 configures.Additionally, back light unit 85 has second zone of reflections 88, described second reflection Configured in the way of covering the back side of one or more low profile light sources 13 side edge of described light guiding film 86 with 88.Second zone of reflections 88 configure the region in light guiding film 86 with the corresponding rear side in region being configured with first zone of reflections 87.This back light unit 85, Because there is second zone of reflections 88 in light guiding film 86 with the region of the corresponding rear side in region being configured with first zone of reflections 87, It is possible to suppression is reflected and is incided the light in light guiding film 86 by first zone of reflections 87 and projects from the rear side of light guiding film 86, The utilization ratio of light can be improved.

The back light unit 89 of Figure 15, the back light unit in addition to the composition of first zone of reflections and second zone of reflections, with Fig. 2 11 is identical.The surface of the prism portion 12b in light guiding film 12 for the one side configuration of the zone of reflections 90 of back light unit 89, and the other end Side configures the back side of main body 12a in light guiding film 12.One zone of reflections 90 of back light unit 89 passes through from the surface of prism portion 12b The side face of one or more low profile light sources 13 sets up the back side of light guiding film 12 always.That is, the one of this back light unit 89 Open the zone of reflections 90 and double as the composition for first zone of reflections and second zone of reflections.Even if this back light unit 89 has such composition, Also the light projecting from one or more low profile light sources 13 can be made rightly to incide in light guiding film 12, thus, it is possible to improve light Utilization ratio, the raising of brightness can be promoted.Additionally, this back light unit 89, because it is anti-to obtain first with a zone of reflections 90 Penetrate the composition of band and second zone of reflections, so configuration is easily, availability might as well.

Additionally, as the light guiding film of described back light unit and the composition of first zone of reflections and second zone of reflections, example As the composition shown in Figure 16 can also be adopted.The light guiding film 95 of Figure 16 is only made up of main body.Additionally, light guiding film 95 has section being The prism portion 96 of triangle, described prism portion 96 is formed by the material different from main body, to be configured with one or more slim light The mode that the end edge surface in source is more gradually increased the closer to end edge side thickness is formed.Additionally, first zone of reflections 97 configures in prism The surface in portion 96, and in the configuration of the region of corresponding with the region being configured with first zone of reflections 97, light guiding film 95 rear side There is second zone of reflections 98.Even if this back light unit has the structure of light guiding film 95 and first zone of reflections 97 and second zone of reflections 98 It is also possible to make the light projecting from one or more low profile light sources accurately incide in light guiding film 95 in the case of one-tenth, thus, it is possible to Enough improve the utilization ratio of light, the raising of brightness can be promoted.

Described light guiding film need not necessarily overleaf have diffusion patterned.As described portable terminal, except as described above Notebook computer beyond, can also enumerate：Portable data assistances such as the mobile phone terminals such as smart mobile phone, tablet terminal etc. are various Portable terminal.

Industrial applicibility

As described above, the edge-lit backlight unit of the present invention and reflection band member can make the light from light source injection proper Locality is incided in light guiding film, thus, it is possible to improve the utilization ratio of light, can promote the raising of brightness, is therefore applied to promotion The liquid crystal indicator of high brightness.

Claims (8)

1. a kind of edge-lit backlight unit, it possesses：Light guiding film, average thickness is less than more than 100 μm 600 μm；And one Or multiple low profile light source, configured in the way of relative with one or more end faces of described light guiding film, described side-light backlight list Unit makes the light projecting from described low profile light source project from the surface of described light guiding film,

Described edge-lit backlight unit is characterised by,

Described edge-lit backlight unit possesses first zone of reflections, and described first zone of reflections is to cover the one of described light guiding film Or the mode of the face side of multiple low profile light source side edge configures.

2. edge-lit backlight unit according to claim 1 is it is characterised in that described first zone of reflections is to cover described one The mode of the face side in space between individual or multiple low profile light sources and described light guiding film configures.

3. edge-lit backlight unit according to claim 1 and 2 is it is characterised in that described edge-lit backlight unit also has Standby second zone of reflections, described second zone of reflections is to cover the space between one or more of low profile light sources and described light guiding film The mode of rear side configure.

4. edge-lit backlight unit as claimed in any of claims 1 to 3 is it is characterised in that described light guiding film has There is the prism portion that section is triangle, described prism portion is more leaned on the end edge surface being configured with one or more of low profile light sources The mode that near-end avris thickness is more gradually increased is formed,

Described first zone of reflections is configured in the way of covering the surface in described prism portion.

5. edge-lit backlight unit as claimed in any of claims 1 to 4 is it is characterised in that described first reflects Band possesses reflecting layer, and described reflecting layer has：Matrix, with resin as main constituent；And Chinese white, it is contained in described matrix.

6. edge-lit backlight unit according to claim 5 is it is characterised in that described first zone of reflections is also equipped with binding agent Layer, described adhesive is laminated on described reflecting layer layer by layer, described first zone of reflections pass through described adhesive layer with one or many Individual low profile light source and the bonding of described light guiding film.

7. edge-lit backlight unit according to claim 6 is it is characterised in that described first zone of reflections is with false tacky state With one or more of low profile light sources and the bonding of described light guiding film.

8. a kind of reflection band member is it is characterised in that described reflection band member is as described in any one in claim 1 to 7 Edge-lit backlight unit first the zone of reflections use.