CN1735768A - Lighting device and image display unit and light guide provided with it - Google Patents
Lighting device and image display unit and light guide provided with it Download PDFInfo
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- CN1735768A CN1735768A CNA2003801084042A CN200380108404A CN1735768A CN 1735768 A CN1735768 A CN 1735768A CN A2003801084042 A CNA2003801084042 A CN A2003801084042A CN 200380108404 A CN200380108404 A CN 200380108404A CN 1735768 A CN1735768 A CN 1735768A
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Abstract
A lighting device comprising a light source (10), and a light guide (20) having an incident surface (20a) for receiving a light emitted from the light source (10) and an output surface (20c) for outputting a light entered via the incident surface (20a). The light guide (20) has a polarization selection layer (22) for selectively outputting via the output surface (20c) a light in a specific polarization direction (first polarization) out of lights incident via the incident surface (20a), and a polarization conversion layer (24) for converting a second polarization different in polarization direction than the first polarization into the first polarization. The polarization selection layer (22) substantially reflects the first polarization toward the output surface (20c) side only.
Description
Technical field
The present invention relates to lighting device, possess the image display device and the light conductor of this device, particularly relate to the high lighting device of light utilization ratio, the image display device that possesses this device and light conductor.
Background technology
In recent years, liquid crystal indicator (Liquid Crystal Display) makes full use of its thin thickness, characteristics low in energy consumption, is widely used in mobile information apparatus such as OA equipment, electronic notebooks such as word processor and PC or possesses among the VTR etc. of camera build of LCD monitor.
The non-light emitting display of liquid crystal indicator representative and CRT (Cathode RayTube: cathode-ray tube), PDP (Plasma Display Panel: plasma display) and EL electroluminescent) etc. (Electro Luminescence: self-luminous display device is different, himself is not luminous, but the optical transmission light quantity and the reflection light quantity that come by the control external irradiation show character and image.
Above-mentioned liquid crystal indicator is divided into transmission-type and reflection-type substantially.
The light that the transmissive liquid crystal display device utilization is configured in display panels lighting device (so-called backlight) behind shows that reflection-type liquid-crystal display device then utilizes surround lighting to show.Yet the reflection-type liquid-crystal display device that has possesses lighting device, and it is used for improving display quality under the situation of the surround lighting that can't obtain sufficient intensity; With respect to " backlight " lighting device of transmissive liquid crystal display device, this lighting device is called as " front light-source ".
The transmissive liquid crystal display device major part of practicability possesses across the opposed a pair of polariscope of liquid crystal cell at present, and in addition, the reflection-type liquid-crystal display device major part of practicability possesses the polariscope that is configured in liquid crystal cell observer one side at present.Therefore, be under the situation of light of polarization state at random when the illumination light that penetrates from lighting device (backlight and front light-source), illumination light had 50% to be polarized mirror and to absorb before injecting liquid crystal cell approximately.
Therefore, in order to reduce polariscope to the absorption of light and improve the utilization ratio of light, a kind of lighting device that penetrates regulation polarization direction light has selectively been proposed.
For example, Te Kaiping 9-5739 communique and Tanase and other five are at " A NewBacklighting System with a Polarizer Light Pipe for EnhancedLight Output from LCDs ", SID97DIGEST discloses that a kind of utilization reflectivity on the interface between the mutually different transparent medium of refractive index has polarization dependence in p.365-368 and the lighting device that penetrates particular polarization light.Figure 43 and Figure 44 have schematically shown and special driven in the flat 9-5739 communique disclosed lighting device 740 and utilize its liquid crystal indicator 700 as backlight.
Penetrate the back from light source 741 and repeated total reflection by exit facet 720c and opposed faces 720d, transmit towards the 2nd side 720b in this way from the light that plane of incidence 720a injects light conductor 720 inside.Part at the light of light conductor 720 internal transmission is reflected at amorphous layer 723a that constitutes light guide sheet 723 and the interface between the 723b, penetrates towards display panels 710 from exit facet 720c.
As everyone knows, on the interface between the mutually different amorphous layer of refractive index, reflectivity is different because of the polarization direction, particularly, when light was injected interface with the specific incidence angle of so-called Brewster's angle, the reflectivity of P polarised light was 0, had only the S polarised light to be reflected.
Therefore, be stacked with constituting the amorphous layer 723a of light guide sheet 723 and 723b exit facet 720c near the angle of Brewster's angle with respect to light conductor 720, can improve the reflectivity of the 1st polarised light of the last vibration of orthogonal direction (direction vertical) with the paper of Figure 44 in the repetition direction of amorphous layer 723a and 723b, and the parallel direction (direction parallel with the paper of Figure 44) that is reduced in the repetition direction of amorphous layer 723a and 723b goes up the reflectivity of the 2nd polarised light of vibration, makes the illumination light that penetrates from light conductor 720 have polarization characteristic.
Be arranged near the 2nd side 720b of light conductor 720 λ/4 plates 732 and reflecting plate 734 and be to be used for making not and penetrate from the exit facet 720c of light conductor 720 but inject light conductor 720 inside once more after having arrived the polarisation of light direction rotation of the 2nd side 720b, improve the utilization ratio of light thus.In addition, being arranged on illumination light that near the opposed faces 720d of light conductor 720 reflecting plate 736 is used for being reflexed to light conductor 720 1 sides by display panels 710 reflexes to display panels 710 1 sides once more and is provided with.
As mentioned above, polarised light specific from lighting device 740 penetrates selectively, therefore, can suppress display panels 710 is possessed in the liquid crystal indicator 700 the polariscope 715b absorption to light, improves the utilization ratio of light.
In addition, Te Biaoping 10-508151 communique, special table 2001-507483 communique, S.M.P, Blom, other 2 at " Towards Polarised Light Emitting BackLights:Micro-structured Anisotropic Layers ", Asia Display/IDW ' 01, p.525-528 and Henri J.B.Jagt, other three at " Micro-structuredPolymeric Linearly Polarized Light Emitting Lightguide for LCDIllumination ", SID02DIGEST, a kind of lighting device has been proposed p.1236-1239, it utilizes, and reflectivity has polarization dependence on the interface between isotropic material of refractive index and the anisotropic material of refractive index, and the light of particular polarization is penetrated.Figure 45 (a) and (b) and Figure 46 schematically shown Asia D1splay/IDW ' 01, p.525-528 in disclosed lighting device 800.
Penetrate the back from light source 810 and repeated total reflection by exit facet 820c and opposed faces 820d, transmit towards the 2nd side 820b simultaneously from the light that plane of incidence 820a injects light conductor 820 inside.After the partial reflection that the part of the light of LGP 820 internal transmission tilts with respect to exit facet 820c in the interface of anisotropic band 823 and isotropic layer 821, penetrate from exit facet 820c and to go.
On the interface of anisotropic band 823 and isotropic layer 821, only the 1st polarised light that vibrates on the mutually different direction of refractive index is reflected, and the 2nd polarised light that vibrates on the roughly the same direction of mutual refractive index is not reflected.Therefore, can make the illumination light that penetrates from light conductor 820 have polarization characteristic.
In lighting device 800, as mentioned above, owing to specific polarised light penetrates selectively from exit facet 820c, so can improve the utilization ratio of light.
A kind of lighting device is also disclosed in the Te Biaoping 10-508151 communique, it is identical with Figure 45 (a) and (b) and lighting device 800 shown in Figure 46, utilizes reflectivity on the interface of isotropic layer and anisotropic band to have polarization dependence and penetrates the light of particular polarization selectively; Wherein further propose,, eliminate reflecting plate 832 by polarization is set near the 2nd side 820b of light conductor 820, to scheme further to improve the utilization ratio of light as Figure 45 (a) and shown in Figure 46.The 2nd polarised light that polarization elimination reflecting plate 832 will not be reflected on the interface of anisotropic band 823 and isotropic layer 821 is eliminated polarization, its part is injected light conductor 820 once more as the 1st polarised light, therefore, can be with the 2nd polarised light as illumination light.
In addition, open in the flat 9-218407 communique the spy and to disclose a kind of lighting device, its utilize isotropic layer (layer that forms by the isotropic material of refractive index) and anisotropic band (by the anisotropic material of refractive index forms layer) interface in the arrangement grating that forms diffraction polarization dependence and penetrate the light of particular polarization.Figure 47 (a) and (b) and Figure 48 schematically shown the spy and driven disclosed lighting device 900 in the flat 9-218407 communique.
Penetrate the back from light source 910 and repeated total reflection by exit facet 920c and opposed faces 920d, transmit towards the 2nd side 920b simultaneously from the light that plane of incidence 920a injects light conductor 920 inside.Arrangement optical grating diffraction in that the part of the light of light conductor 920 internal transmission forms on the interface of anisotropic band 923 and isotropic layer 921 penetrates from exit facet 920c.
In the arrangement grating that forms on the interface of anisotropic band 923 and isotropic layer 921, only the 1st polarised light that vibrates on the mutually different direction of refractive index is diffracted, and the 2nd polarised light that vibrates on the roughly the same direction of mutual refractive index is not diffracted.Therefore, can make the illumination light that penetrates from light conductor 920 have polarization characteristic.
In lighting device 900, as mentioned above, owing to specific polarised light penetrates selectively from exit facet 920c, so can improve the utilization ratio of light.
In addition, it is described to open flat 9-218407 communique according to the spy, without the 2nd polarised light of arranging optical grating diffraction in light conductor 920 inside in the process of the 2nd side 920b transmission, be transformed to the 1st polarised light by anisotropic band 923 and retardation plate 932, therefore, also can be with the 2nd polarised light as illumination light.
But all there is following problem in above-mentioned lighting device.
In Figure 43 and lighting device shown in Figure 44 740, Figure 45 and the lighting device shown in Figure 46 800, eliminate reflecting plate 832 at the 2nd polarised light that the interface of the interface between amorphous layer 723a and the 723b and isotropic layer 821 and anisotropic band 823 is not directly reflected via near the λ the 2nd side 720b that is arranged on light conductor 720/4 plates 732 and reflecting plate 734, near be arranged on the 2nd side 820b of light conductor 820 polarization, be transformed to the 1st polarised light.
Usually has birefringence slightly as transparent resins such as the polymethyl methacrylate of light conductor material or Merlon, eliminate reflecting plate 832 for the 2nd polarised light that makes the 2nd side 720a, the 820a that arrive light conductor 720,820 via λ/4 plates 732 and reflecting plate 734 or polarization and be transformed to the 1st polarised light, need be controlled to be the birefringence of light conductor 720,820 enough little.This is because if light conductor 720,820 has very big birefringence, then the part at the 2nd polarised light of light conductor 720,820 internal transmission can be polarized elimination, becomes the 1st polarised light and arrives the 2nd side; Therefore, eliminate reflecting plate 832 via λ/4 plates 732 and reflecting plate 734 or polarization and be transformed to the 2nd polarised light,, also can not penetrate and go towards exit facet 720c, 820c even inject light conductor 720,820 once more.
Therefore, in lighting device 740 and 800, must use the enough little material of birefringence to form light conductor 720,820, alternative material is limited.
In addition, in recent years, the remarkable attenuation of liquid crystal indicator, what the thickness of the 2nd side 720b, the 820b of light conductor 720,820 had reaches about 0.7mm～0.8mm.Near the 2nd side 720b, the 820b of such light conductor 720,820, dispose λ/4 plates 732 and reflecting plate 734 or polarization accurately and eliminate reflecting plate 832, not only very difficult on producing, and, consider the trend of the further attenuation of liquid crystal indicator from now on, can think that this structure lacks practicality.
On the other hand, in Figure 47 and the lighting device 900 shown in Figure 48, the 2nd polarised light is transformed to the 1st polarised light via anisotropic band 923, and this records and narrates in patent documentation 4 to some extent; But the 1st polarised light in this lighting device 900 and the 2nd polarised light are equivalent to normal light and unusual light respectively with respect to anisotropic band 923, and therefore, theoretically, the 2nd polarised light can not be transformed to the 1st polarised light via the birefringence of anisotropic band 923.Therefore, in lighting device 900, mainly utilize retardation plate 932 to carry out the conversion of the 2nd polarised light to the 1 polarised light.
But, do not record and narrate the concrete specification of retardation plate 932 in the Te Kaiping 9-218407 communique fully, for example the anisotropy of refractive index, thickness and optical axis (slow axes and fast axis) direction etc. does not disclose any relevant opinion that the 2nd polarised light is transformed to efficiently the 1st polarised light.
In addition, in this lighting device 900, the arrangement grating that forms on the interface via isotropic layer 921 and anisotropic band 923, light also at opposed faces 920d one side diffraction, also has many light to penetrate from opposed faces 920d not only in exit facet 920c one side.Therefore, the utilization ratio of light reduces.In addition, if this lighting device 900 is used as front light-source, then also have light to penetrate in observer's one side, therefore, display quality descends.
As mentioned above, present situation is that the still untapped light that goes out light source to be sent is as the abundant lighting device that penetrates efficiently of the light of particular polarization.
Summary of the invention
The present invention be directed to the problems referred to above point and propose, purpose is to provide the light that light source can be sent to penetrate lighting device and image display device that possesses this lighting device and the light conductor that goes fully efficiently as the light of particular polarization.
The 1st lighting device of the present invention possesses: light source; And light conductor, has acceptance from the plane of incidence of the light of above-mentioned light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, above-mentioned light conductor has: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization; Above-mentioned polarised light selects layer in fact only the light of above-mentioned particular polarization to be reflexed to above-mentioned exit facet one side, realizes above-mentioned purpose with this.
Above-mentioned polarised light selects layer also can comprise a plurality of dielectric films that become predetermined angular with above-mentioned exit facet.
The 2nd lighting device of the present invention possesses: light source; And light conductor, has acceptance from the plane of incidence of the light of above-mentioned light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, above-mentioned light conductor has: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization; Above-mentioned polarised light selection layer comprises a plurality of dielectric films with respect to above-mentioned exit facet inclination, and the above-mentioned plane of incidence of a plurality of dielectric films distances of above-mentioned inclination is far away more, and its configuration is intensive more; Realize above-mentioned purpose with this.
Above-mentioned light conductor comprises with lower member and constitutes: the 1st parts, have a plurality of inclined planes of comprising to tilt with respect to above-mentioned exit facet and with the interarea of a plurality of parallel surfaces of above-mentioned exit facet almost parallel; And the 2nd parts, be arranged on the above-mentioned interarea of above-mentioned the 1st parts, make above-mentioned interarea planarization; Its structure can be, a plurality of dielectric films of above-mentioned inclination are formed on above-mentioned a plurality of inclined planes of above-mentioned interarea, and the above-mentioned plane of incidence of above-mentioned a plurality of parallel surfaces distances of above-mentioned interarea is far away more, and its configuration is sparse more.
Above-mentioned polarised light selects layer also can be additionally contained in a plurality of dielectric films that form on above-mentioned a plurality of parallel surfaces of above-mentioned interarea.
Above-mentioned polarised light selects layer to be configured near the above-mentioned exit facet, and, can be than more close above-mentioned exit facet one side of above-mentioned polarised light transform layer.At this moment, above-mentioned a plurality of parallel surface is preferably than more close above-mentioned exit facet one side in above-mentioned a plurality of inclined planes.
Above-mentioned light conductor also has the opposed faces relative with above-mentioned exit facet, and above-mentioned polarised light selects layer to be configured near the above-mentioned opposed faces, and, can be than more close above-mentioned opposed faces one side of above-mentioned polarised light transform layer.At this moment, above-mentioned a plurality of parallel surface is preferably than more close above-mentioned opposed faces one side in above-mentioned a plurality of inclined planes.
Above-mentioned the 1st parts are prismatic lenses of for example having arranged a plurality of prisms on above-mentioned interarea.
Above-mentioned the 2nd parts are the transparent resin layers that for example formed by transparent resin material.
Above-mentioned polarised light transform layer also can be formed by the transparent material with birefringence.
Above-mentioned polarised light transform layer also can be by the transparent resin layer of ejection formation.
Above-mentioned polarised light transform layer also can be a retardation plate.
Slow axes that preferably above-mentioned retardation plate is had in being parallel to the face of above-mentioned exit facet and fast axis and above-mentioned particular polarization are inconsistent.
The 3rd lighting device of the present invention possesses: light source; And light conductor, has acceptance from the plane of incidence of the light of above-mentioned light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, above-mentioned light conductor has: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization; Above-mentioned polarised light transform layer is the transparent resin layer with birefringence by ejection formation, realizes above-mentioned purpose with this.
The 4th lighting device of the present invention possesses: light source; And light conductor, has acceptance from the plane of incidence of the light of above-mentioned light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, above-mentioned light conductor has: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization; Above-mentioned polarised light transform layer is a retardation plate, has slow axes and fast axis and the inconsistent structure of above-mentioned particular polarization that above-mentioned retardation plate is had in being parallel to the face of above-mentioned exit facet, realizes above-mentioned purpose with this.
The structure of above-mentioned retardation plate also can have the refractive index anisotropy of uniaxiality.
Above-mentioned retardation plate has under the anisotropic situation of refractive index of uniaxiality, along the axial refractive index n of above-mentioned slower rays of above-mentioned retardation plate
x, along the refractive index n of the above-mentioned fast axis direction of above-mentioned retardation plate
y, along the refractive index n of the thickness direction of above-mentioned retardation plate
z, above-mentioned retardation plate the above-mentioned slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate preferably satisfy (n
x-n
z)/(n
x-n
y) 0 and 0＜(n
x-n
y) relation of d＜λ and 10 °＜α＜30 ° or 40 °＜α＜60 °; Further, along the axial refractive index n of above-mentioned slower rays of above-mentioned retardation plate
x, along the refractive index n of the above-mentioned fast axis direction of above-mentioned retardation plate
y, along the refractive index n of the thickness direction of above-mentioned retardation plate
z, above-mentioned retardation plate the above-mentioned slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate preferably satisfy (n
x-n
z)/(n
x-n
y) 0, (n
x-n
y) relation of d=λ/2 and 10 °＜α＜30 °.
Perhaps, along the axial refractive index n of above-mentioned slower rays of above-mentioned retardation plate
x, along the refractive index n of the above-mentioned fast axis direction of above-mentioned retardation plate
y, along the refractive index n of the thickness direction of above-mentioned retardation plate
z, above-mentioned retardation plate the above-mentioned slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate preferably satisfy (n
x-n
z)/(n
x-n
y) 1, λ/4＜(n
x-n
y) relation of d＜5 λ/4 and 20 °＜α＜90 °; Further, along the axial refractive index n of above-mentioned slower rays of above-mentioned retardation plate
x, along the refractive index n of the above-mentioned fast axis direction of above-mentioned retardation plate
y, along the refractive index n of the thickness direction of above-mentioned retardation plate
z, above-mentioned retardation plate the above-mentioned slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate preferably satisfy (n
x-n
z)/(n
x-n
y) 1, (n
x-n
y) relation of d=λ/2 and 20 °＜α＜80 °.
In addition, the structure of above-mentioned retardation plate also can have the refractive index anisotropy of biaxiality.
Above-mentioned retardation plate has under the anisotropic situation of refractive index of biaxiality, along the axial refractive index n of above-mentioned slower rays of above-mentioned retardation plate
x, along the refractive index n of the above-mentioned fast axis direction of above-mentioned retardation plate
y, along the refractive index n of the thickness direction of above-mentioned retardation plate
z, above-mentioned retardation plate the above-mentioned slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate preferably satisfy 0.6＜(n
x-n
z)/(n
x-n
y)＜0.9, λ/4＜(n
x-n
y) relation of d＜3 λ/4 and 60 °＜α＜80 °; Further, along the axial refractive index n of above-mentioned slower rays of above-mentioned retardation plate
x, along the refractive index n of the above-mentioned fast axis direction of above-mentioned retardation plate
y, along the refractive index n of the thickness direction of above-mentioned retardation plate
z, above-mentioned retardation plate the above-mentioned slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate preferably satisfy 0.6＜(n
x-n
z)/(n
x-n
y)＜0.9, (n
x-n
y) relation of d=λ/2 and 60 °＜α＜80 °.
Above-mentioned polarised light transform layer also can be configured in respect to above-mentioned polarised light and select the opposite side with above-mentioned exit facet of layer.
Above-mentioned polarised light transform layer also can be configured in above-mentioned exit facet one side of selecting layer with respect to above-mentioned polarised light.
Image display device of the present invention has: the lighting device with said structure; Be configured in the above-mentioned light conductor that above-mentioned lighting device has above-mentioned exit facet one side, possess at least 1 polariscopic display floater; Realize above-mentioned purpose with this.
Above-mentioned lighting device also can also possess the transparent input unit that forms on the above-mentioned opposed faces of above-mentioned light conductor.
Above-mentioned display floater comprises substrate, and the above-mentioned light conductor that above-mentioned lighting device had also can the double as aforesaid substrate.
The 1st light conductor of the present invention has acceptance from the plane of incidence of the light of light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, wherein, also have: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization, above-mentioned polarised light selects layer in fact only the light of above-mentioned particular polarization to be reflexed to above-mentioned exit facet one side, realizes above-mentioned purpose with this.
The 2nd light conductor of the present invention has acceptance from the plane of incidence of the light of light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, wherein, also have: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization, above-mentioned polarised light selection layer comprises a plurality of dielectric films with respect to above-mentioned exit facet inclination, the above-mentioned plane of incidence of a plurality of dielectric film distances of above-mentioned inclination is far away more, and its configuration is intensive more; Realize above-mentioned purpose with this.
The 3rd light conductor of the present invention has acceptance from the plane of incidence of the light of light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, wherein, also have: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization, and above-mentioned polarised light transform layer is the transparent resin layer with birefringence by ejection formation, realizes above-mentioned purpose with this.
The 4th light conductor of the present invention has acceptance from the plane of incidence of the light of light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, wherein, also have: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization, above-mentioned polarised light transform layer is a retardation plate, have slow axes and fast axis and the inconsistent structure of above-mentioned particular polarization that above-mentioned retardation plate is had in being parallel to the face of above-mentioned exit facet, realizing above-mentioned purpose with this.
The following describes effect of the present invention.
In the 1st lighting device of the present invention, light conductor possesses: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with this particular polarization is transformed to the light of this particular polarization; Therefore, the light of injecting in the light conductor via the plane of incidence from light source can be penetrated as the light of particular polarization efficiently.Therefore, the utilization ratio of light improves.Further, polarised light selects layer in fact only the light of particular polarization to be reflexed to exit facet one side, therefore, can suppress light descends and display quality (contrast) decline in the utilization ratio of the caused light of reflection of opposed faces one side (observer's one side during front light-source).
It is to comprise a plurality of dielectric films that become predetermined angular with respect to exit facet that polarised light is selected the structure of layer, and thus, polarised light selects layer the light of particular polarization in fact only can be reflexed to exit facet one side.
In the 2nd lighting device of the present invention, light conductor possesses: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with this particular polarization is transformed to the light of this particular polarization; Therefore, the light of injecting in the light conductor via the plane of incidence from light source can be penetrated as the light of particular polarization efficiently.Therefore, the utilization ratio of light improves.Polarised light selection layer comprises a plurality of dielectric films with respect to the exit facet inclination, and the dielectric film of these inclinations reflexes to exit facet one side with the light of particular polarization.In the 2nd lighting device of the present invention, a plurality of dielectric films of inclination are far away more apart from the plane of incidence, and its configuration is intensive more, and therefore, the light intensity uniformity that penetrates from exit facet improves.
In the 2nd lighting device of the present invention, for example, above-mentioned light conductor comprises with lower member and constitutes: the 1st parts, have a plurality of inclined planes of comprising to tilt with respect to exit facet and with the interarea of a plurality of parallel surfaces of exit facet almost parallel; And the 2nd parts, be arranged on the interarea of the 1st parts, make the interarea planarization; And, on a plurality of inclined planes of interarea, form a plurality of dielectric films of inclination, further, a plurality of parallel surfaces of interarea are far away more apart from the plane of incidence, and its configuration is sparse more, can be convenient to thus make.
When polarised light selects the structure of layer also to have a plurality of dielectric films (promptly being roughly parallel to the dielectric film of exit facet) that form on a plurality of parallel surfaces at interarea, the structure that is adopted preferably makes these parallel dielectric films can not influence the incident of light for the polarised light transform layer, and makes parallel dielectric film can not influence the incident of light for the dielectric film that tilts.Particularly, preferably adopt following structure.
At first, in the time of near polarised light selection layer is configured in exit facet, if polarised light selects layer to be positioned at the position of more close exit facet one side of ratio polarization light transform layer, then light can not be subjected to the influence of parallel dielectric film for the incident of polarised light transform layer, therefore, can be specific polarization direction suitably with changeable direction of polarization.In addition, at this moment, if the parallel surface of the 1st parts is than more close exit facet one side in inclined plane, if promptly parallel dielectric film is than more close exit facet one side of dielectric film that tilts, then parallel dielectric film can not influence light and arrive the inclination dielectric film, can make the suitably ejaculation of light from exit facet.
In addition, when light conductor also has the opposed faces relative with exit facet, polarised light and selects layer to be configured near the opposed faces, if polarised light is selected more close opposed faces one side of layer ratio polarization light transform layer, then light can not be subjected to the influence of parallel dielectric film for the incident of polarised light transform layer, therefore, can be specific polarization direction suitably with changeable direction of polarization.In addition, at this moment, if the parallel surface of the 1st parts is than more close opposed faces one side in inclined plane, if promptly parallel dielectric film is than more close opposed faces one side of dielectric film that tilts, then parallel dielectric film can not influence light and arrive the inclination dielectric film, and light is suitably penetrated from exit facet.
Above-mentioned the 1st parts can use the prismatic lens of for example having arranged a plurality of prisms on interarea.In addition, the 2nd parts can use the transparent resin layer that is for example formed by transparent resin material.
The polarised light transform layer is typically and is formed by the transparent material with birefringence.
The polarised light transform layer is if the transparent resin layer of ejection formation, then be easy to the structure that forms thick polarised light transform layer, occupy light conductor than multizone, therefore, can in the polarised light transform layer, transmit more light, efficiently light is transformed to the light of particular polarization.In addition, if the polarised light transform layer is a retardation plate, its slow axes roughly the same in being parallel to the plane of exit facet (unanimity) then, therefore, the efficient of light that light is transformed to particular polarization is roughly the same in being parallel to the plane of exit facet.Therefore, realize penetrating equably the light of particular polarization easily from exit facet.
Because slow axes that retardation plate is had in being parallel to the face of exit facet and fast axis and above-mentioned specific polarization direction are inconsistent, so retardation plate is suitable as the polarised light transform layer.
In the 3rd lighting device of the present invention, light conductor possesses: polarised light is selected layer, will penetrate from exit facet selectively by the light of particular polarization from the light that the plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with this particular polarization is transformed to the light of this particular polarization; Therefore, the light of injecting in the light conductor via the plane of incidence from light source can be penetrated as the light of particular polarization efficiently.Therefore, the utilization ratio of light improves.Further, the polarised light transform layer is the transparent resin layer with birefringence of ejection formation, therefore, is easy to the structure than multizone that forms thick polarised light transform layer, occupies light conductor.Therefore, can in the polarised light transform layer, transmit more light, efficiently light is transformed to the light of particular polarization.
In the 4th lighting device of the present invention, light conductor possesses: polarised light is selected layer, will penetrate from exit facet selectively by the light of particular polarization from the light that the plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with this particular polarization is transformed to the light of this particular polarization; Therefore, the light of injecting in the light conductor via the plane of incidence from light source can be penetrated as the light of particular polarization efficiently.Therefore, the utilization ratio of light improves.In addition, because the polarised light transform layer is a retardation plate, its slow axes roughly the same in being parallel to the plane of exit facet (unanimity).Therefore, it is roughly the same in being parallel to the plane of exit facet that light is transformed to the efficient of light of particular polarization.Therefore, realize penetrating equably the light of particular polarization easily from exit facet.Further, because slow axes that this retardation plate is had in being parallel to the face of exit facet and fast axis and above-mentioned specific polarization direction are inconsistent, so this retardation plate is suitable as the polarised light transform layer.
Retardation plate also can have the refractive index anisotropy of uniaxiality.
When retardation plate is uniaxiality, along the axial refractive index n of the slower rays of retardation plate
x, along the refractive index n of the fast axis direction of retardation plate
y, along the refractive index n of the thickness direction of retardation plate
z, if the slow axes angulation α of thickness d, visible wavelength λ and the above-mentioned particular polarization and the retardation plate of retardation plate satisfies (n
x-n
z)/(n
x-n
y) 0 and 0＜(n
x-n
y) relation of d＜λ and 10 °＜α＜30 ° or 40 °＜α＜60 °, then can efficiently light be transformed to specific polarization direction.Particularly, if satisfy (n
x-n
z)/(n
x-n
y) 0, (n
x-n
y) d=λ/2 and and the relation of 10 °＜α＜30 °, then since conversion efficiency in the wavelength of visible light scope basically not with wavelength change, so suppressed the generation of color.
In addition, when retardation plate is uniaxiality, along the axial refractive index n of the slower rays of retardation plate
x, along the refractive index n of the fast axis direction of retardation plate
y, along the refractive index n of the thickness direction of retardation plate
z, if the slow axes angulation α of thickness d, visible wavelength λ and the above-mentioned particular polarization and the retardation plate of retardation plate satisfies (n
x-n
z)/(n
x-n
y) 1, λ/4＜(n
x-n
y) relation of d＜5 λ/4 and 20 °＜α＜90 °, also can efficiently light be transformed to specific polarization direction.Particularly, if satisfy (n
x-n
z)/(n
x-n
y) 1, (n
x-n
y) relation of d=λ/2 and 20 °＜α＜80 °, then since conversion efficiency in the wavelength of visible light scope basically not with wavelength change, so suppressed the generation of color.
In addition, retardation plate also can have the refractive index anisotropy of biaxiality.When retardation plate is biaxiality, along the axial refractive index n of the slower rays of retardation plate
x, along the refractive index n of the fast axis direction of retardation plate
y, along the refractive index n of the thickness direction of retardation plate
z, if the slow axes angulation α of thickness d, visible wavelength λ and the above-mentioned particular polarization and the retardation plate of retardation plate satisfies 0.6＜(n
x-n
z)/(n
x-n
y)＜0.9, λ/4＜(n
x-n
y) relation of d＜3 λ/4 and 60 °＜α＜80 °, then can efficiently light be transformed to specific polarization direction in the angular range (scope of transmission of angle) widely.Particularly, if satisfy 0.6＜(n
x-n
z)/(n
x-n
y)＜0.9, (n
x-n
y) relation of d=λ/2 and 60 °＜α＜80 °, then since conversion efficiency in the wavelength of visible light scope basically not with wavelength change, so suppressed the generation of color.
The polarised light transform layer both can be configured in respect to polarised light and select a layer side (with exit facet opposed opposed faces one side) opposite with exit facet, also can be configured in exit facet one side.
Yet when the polarised light transform layer was the transparent resin layer of ejection formation, the polarised light transform layer preferably was configured in respect to polarised light and selects a layer side (opposed faces one side) opposite with exit facet.When the polarised light transform layer was the transparent resin layer of ejection formation, the slow axes of polarised light transform layer was discrete state in being parallel to the plane of exit facet; If polarised light is selected layer to be configured in respect to polarised light and is selected a layer side (opposed faces one side) opposite with exit facet, then select layer before penetrating, can not pass the polarised light transform layer, can not be polarized the light transform layer and eliminate polarization from exit facet towards the light of the particular polarization of exit facet by means of polarised light.
In addition, when the polarised light transform layer is retardation plate, because the slow axes of polarised light transform layer is roughly consistent in being parallel to the plane of exit facet, so if the polarised light transform layer is configured in exit facet one side of selecting layer with respect to polarised light, just can utilize this polarised light transform layer (retardation plate) control to select the polarized state of light (for example polarization direction) of layer towards the particular polarization of exit facet by means of polarised light.
Lighting device of the present invention is applicable to image display device.Lighting device of the present invention and be arranged on the light conductor that lighting device has exit facet one side, have the utilization ratio that the image display device that possesses 1 polariscopic display floater at least can improve light, realize bright demonstration.
In this image display device, if on the opposed faces of the light conductor that lighting device had, form transparent input unit (so-called touch panel), compare with the situation that transparent input unit, lighting device and display floater are stacked simply, can realize the slimming of image display device.Can select layer and polarised light transform layer to obtain by for example in known transparent input unit, adding polarised light at the light conductor that has formed transparent input unit on the opposed faces.
In addition, in this image display device, when display floater comprises substrate, if double this substrate of doing of the light conductor that lighting device had then with simple stacked the comparing of lighting device and display floater, can be realized the slimming of image display device.
The 1st light conductor of the present invention possesses: polarised light is selected layer, will penetrate from exit facet selectively by the light of particular polarization from the light that the plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with this particular polarization is transformed to the light of this particular polarization; Therefore, the light of injecting in the light conductor via the plane of incidence from light source can be penetrated as the light of particular polarization efficiently.Therefore, the utilization ratio of light improves.Further, polarised light selects layer in fact only the light of particular polarization to be reflexed to exit facet one side, therefore, can suppress light descends and display quality (contrast) decline in the utilization ratio of the caused light of reflection of opposed faces one side (observer's one side during front light-source).
The 2nd light conductor of the present invention possesses: polarised light is selected layer, will penetrate from exit facet selectively by the light of particular polarization from the light that the plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with this particular polarization is transformed to the light of this particular polarization; Therefore, the light of injecting in the light conductor via the plane of incidence from light source can be penetrated as the light of particular polarization efficiently.Therefore, the utilization ratio of light improves.Polarised light selection layer comprises a plurality of dielectric films with respect to the exit facet inclination, and the dielectric film of these inclinations reflexes to exit facet one side with the light of particular polarization.In the 2nd light conductor of the present invention, a plurality of dielectric films of inclination are far away more apart from the plane of incidence, and its configuration is intensive more, and therefore, the light intensity uniformity that penetrates from exit facet improves.
The 3rd light conductor of the present invention possesses: polarised light is selected layer, will penetrate from exit facet selectively by the light of particular polarization from the light that the plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with this particular polarization is transformed to the light of this particular polarization; Therefore, the light of injecting in the light conductor via the plane of incidence from light source can be penetrated as the light of particular polarization efficiently.Therefore, the utilization ratio of light improves.Further, the polarised light transform layer is the transparent resin layer with birefringence of ejection formation, therefore, is easy to the structure than multizone that forms thick polarised light transform layer, occupies light conductor.Therefore, can in the polarised light transform layer, transmit more light, efficiently light is transformed to the light of particular polarization.
The 4th light conductor of the present invention possesses: polarised light is selected layer, will penetrate from exit facet selectively by the light of particular polarization from the light that the plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with this particular polarization is transformed to the light of this particular polarization; Therefore, the light of injecting in the light conductor via the plane of incidence from light source can be penetrated as the light of particular polarization efficiently.Therefore, the utilization ratio of light improves.In addition, because the polarised light transform layer is a retardation plate, so its slow axes roughly the same in being parallel to the plane of exit facet (unanimity).Therefore, it is roughly the same in being parallel to the plane of exit facet that light is transformed to the efficient of light of particular polarization.Therefore, realize penetrating equably the light of particular polarization easily from exit facet.Further, because slow axes that this retardation plate is had in being parallel to the face of exit facet and fast axis and above-mentioned specific polarization direction are inconsistent, so this retardation plate is suitable as the polarised light transform layer.
Description of drawings
Fig. 1 is the cutaway view that schematically shows the lighting device 120 of the 1st embodiment of the present invention and possess the liquid crystal indicator (image display device) 100 of this lighting device 120.
Fig. 2 schematically shows the cutaway view of light in the transmission situation of light conductor 20 inside of lighting device 120.
Fig. 3 (a), Fig. 3 (b) and Fig. 3 (c) are the operation cutaway views of manufacturing process that schematically shows the lighting device 120 of the 1st embodiment.
Fig. 4 be in the lighting device 120 of expression the 1st embodiment from the angle of emergence of the light of exit facet 20c (°) and relative brightness (arbitrary unit; The chart of relation a.u.).
Fig. 5 is the cutaway view that schematically shows the lighting device 220 of the 2nd embodiment of the present invention and possess the liquid crystal indicator (image display device) 200 of this lighting device 120.
Fig. 6 schematically shows the cutaway view of light in the transmission situation of light conductor 20 inside of lighting device 220.
Fig. 7 (a), Fig. 7 (b) and Fig. 7 (c) are the operation cutaway views of manufacturing process that schematically shows the lighting device 220 of the 2nd embodiment.
Fig. 8 be in the lighting device 220 of expression the 2nd embodiment from the angle of emergence of the light of exit facet 20c (°) and relative brightness (arbitrary unit; The chart of relation a.u.).
Fig. 9 schematically shows in the lighting device 200 along the axial refractive index n of the slower rays of retardation plate
x, along the refractive index n of the fast axis direction of λ retardation plate
y, along the refractive index n of the thickness direction of retardation plate
z, the polarization direction P of the thickness d of retardation plate and the 1st polarised light and retardation plate the stereogram of relation of slow axes angulation α.
Figure 10 (a) be illustrated in the 2nd polarised light under the situation that light for λ=550nm used λ/4 plates (Nz=0 and uniaxialities) pass for 2 times the efficient (ratio) that is transformed to the 1st polarised light behind the retardation plate and light the angle of retardation plate internal transmission (°) the chart of relation, Figure 10 (b) be illustrated in efficient (ratio) and the transmission of angle that the situation down conversion that this λ/4 plates are configured to α=50 ° is the 1st polarised light (°) the chart of relation.
Figure 11 (a) be illustrated in light for λ=550nm used the situation down conversion of λ/2 plates (Nz=0 and uniaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation, Figure 11 (b) be illustrated in situation down conversion efficient (ratio) that this λ/2 plates are configured to α=20 ° and transmission of angle (°) the chart of relation.
Figure 12 (a) be illustrated in light for λ=550nm used the situation down conversion of 3 λ/4 plates (Nz=0 and uniaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation, Figure 12 (b) be illustrated in situation down conversion efficient (ratio) that this 3 λ/4 plates are configured to α=20 ° and transmission of angle (°) the chart of relation.
Figure 13 (a) be illustrated in light for λ=550nm used the situation down conversion of λ plate (Nz=0 and uniaxiality) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation, Figure 13 (b) be illustrated in situation down conversion efficient (ratio) that this λ plate is configured to α=40 ° and transmission of angle (°) the chart of relation.
Figure 14 be illustrated in light for λ=550nm used the situation down conversion of λ/4 plates (Nz=1 and uniaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation.
Figure 15 (a) be illustrated in light for λ=550nm used the situation down conversion of λ/2 plates (Nz=1 and uniaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation, Figure 15 (b) be illustrated in situation down conversion efficient (ratio) that this λ/2 plates are configured to α=70 ° and transmission of angle (°) the chart of relation.
Figure 16 (a) be illustrated in light for λ=550nm used the situation down conversion of 3 λ/4 plates (Nz=1 and uniaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation, Figure 16 (b) be illustrated in situation down conversion efficient (ratio) that this 3 λ/4 plates are configured to α=80 ° and transmission of angle (°) the chart of relation.
Figure 17 (a) be illustrated in light for λ=550nm used the situation down conversion of λ plate (Nz=1 and uniaxiality) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation, Figure 17 (b) be illustrated in situation down conversion efficient (ratio) that this λ plate is configured to α=80 ° and transmission of angle (°) the chart of relation.
Figure 18 (a) be illustrated in light for λ=550nm used the situation down conversion of 5 λ/4 plates (Nz=1 and uniaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation, Figure 18 (b) be illustrated in situation down conversion efficient (ratio) that this 5 λ/4 plates are configured to α=60 ° and transmission of angle (°) the chart of relation.
Figure 19 be illustrated in light for λ=550nm used the situation down conversion of λ/4 plates (Nz=0.5 and biaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation.
Figure 20 be illustrated in light for λ=550nm used the situation down conversion of λ/2 plates (Nz=0.9 and biaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation.
Figure 21 (a) be illustrated in light for λ=550nm used the situation down conversion of λ/2 plates (Nz=0.8 and biaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation, Figure 21 (b) be illustrated in situation down conversion efficient (ratio) that this λ/2 plates are configured to α=70 ° and transmission of angle (°) the chart of relation.
Figure 22 (a) be illustrated in light for λ=550nm used the situation down conversion of λ/2 plates (Nz=0.7 and biaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation, Figure 22 (b) be illustrated in situation down conversion efficient (ratio) that this λ/2 plates are configured to α=70 ° and transmission of angle (°) the chart of relation.
Figure 23 be illustrated in light for λ=550nm used the situation down conversion of λ/2 plates (Nz=0.6 and biaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation.
Figure 24 (a) be illustrated in light for λ=550nm used the situation down conversion of 3 λ/4 plates (Nz=0.2 and biaxialities) be the 1st polarised light efficient (ratio) and transmission of angle (°) the chart of relation, Figure 24 (b) be illustrated in situation down conversion efficient (ratio) that this λ/2 plates are configured to α=20 ° and transmission of angle (°) the chart of relation.
Figure 25 is the cutaway view that schematically shows the lighting device 320 of the 3rd embodiment of the present invention and possess the liquid crystal indicator (image display device) 300 of this lighting device 320.
Figure 26 schematically shows the cutaway view of light in the transmission situation of light conductor 20 inside of lighting device 320.
Figure 27 is shown schematically in distance lambda to penetrate in the intensive more light conductor 20 of face 20a dielectric film 22a far away more configuration cutaway view from the ejaculation situation of the light of exit facet 20c.
Figure 28 is the cutaway view that is shown schematically in the light conductor 20 that dielectric film 22a is same configuration from the ejaculation situation of the light of exit facet 20c.
Figure 29 (a), Figure 29 (b) and Figure 29 (c) are the operation cutaway views of manufacturing process that schematically shows the lighting device 320 of the 3rd embodiment.
Figure 30 (a) and Figure 30 (b) are the cutaway views that the expression polarised light is selected the configuration mode of layer 22 and polarised light transform layer 24.
Figure 31 be in the lighting device 320 of expression the 3rd embodiment from the angle of emergence of the light of exit facet 20c (°) and relative brightness (arbitrary unit; The chart of relation a.u.).
Figure 32 schematically shows in the lighting device 320 along the axial refractive index n of the slower rays of retardation plate
x, along the refractive index n of the fast axis direction of λ retardation plate
y, along the refractive index n of the thickness direction of retardation plate
z, the polarization direction P of the thickness d of retardation plate and the 1st polarised light and retardation plate the stereogram of relation of slow axes angulation α.
Figure 33 (a) and Figure 33 (b) are the cutaway views that the expression polarised light is selected the configuration mode of layer 22 and polarised light transform layer 24.
Figure 34 (a) and Figure 34 (b) are the cutaway views of expression inclination dielectric film 22a and the configuration mode of parallel dielectric film 22b.
Figure 35 (a) and Figure 35 (b) are the cutaway views of expression inclination dielectric film 22a and the configuration mode of parallel dielectric film 22b.
Figure 36 is the cutaway view that schematically shows the lighting device 420 of the 4th embodiment of the present invention and possess the liquid crystal indicator (image display device) 400 of this lighting device 420.
Figure 37 be in the lighting device 420 of expression the 4th embodiment from the angle of emergence of the light of exit facet 20c (°) and relative brightness (arbitrary unit; The chart of relation a.u.).
Figure 38 schematically shows in the lighting device 420 along the axial refractive index n of the slower rays of retardation plate
x, along the refractive index n of the fast axis direction of λ retardation plate
y, along the refractive index n of the thickness direction of retardation plate
z, the polarization direction P of the thickness d of retardation plate and the 1st polarised light and retardation plate the stereogram of relation of slow axes angulation α.
Figure 39 is the cutaway view that schematically shows the lighting device 520 of the 5th embodiment of the present invention and possess the liquid crystal indicator (image display device) 500 of this lighting device 520.
Figure 40 (a), Figure 40 (b) and Figure 40 (c) are the operation cutaway views of manufacturing process that schematically shows the lighting device 520 of the 5th embodiment.
Figure 41 is the cutaway view that schematically shows the lighting device 620 of the 6th embodiment of the present invention and possess the liquid crystal indicator (image display device) 600 of this lighting device 620.
Figure 42 (a), Figure 42 (b) and Figure 42 (c) are the operation cutaway views of manufacturing process that schematically shows the lighting device 620 of the 6th embodiment.
Figure 43 is the cutaway view that schematically shows existing lighting device 740 and possess the liquid crystal indicator 700 of this lighting device 740.
Figure 44 schematically shows the cutaway view of light in the transmission situation of light conductor 720 inside of lighting device 740.
Figure 45 (a) is the cutaway view that schematically shows existing lighting device 800, and Figure 45 (b) is the enlarged drawing of the area surrounded 45B of dotted line institute among Figure 45 (a).
Figure 46 schematically shows the cutaway view of light in the transmission situation of light conductor 820 inside of lighting device 800.
Figure 47 (a) is the cutaway view that schematically shows existing lighting device 900, and Figure 47 (b) is the enlarged drawing of the area surrounded 47B of dotted line institute among Figure 47 (a).
Figure 48 schematically shows the cutaway view of light in the transmission situation of light conductor 920 inside of lighting device 900.
The specific embodiment
Embodiments of the present invention are described with reference to the accompanying drawings.But the present invention is not limited to following embodiment.
(the 1st embodiment)
At first, with reference to Fig. 1 the lighting device 120 of embodiments of the present invention is described and possesses the structure of the liquid crystal indicator (image display device) 100 of this lighting device 120.
As shown in Figure 1, liquid crystal indicator 100 is the reflection-type liquid-crystal display devices that possess reflective liquid crystal display floater 110, lighting device (front light-source) 120.
Reflective liquid crystal display floater 110 is known reflective liquid crystal display floaters, and here, it has a pair of substrate (for example glass substrate) 111 and 112 and be arranged on liquid crystal layer 113 between them.Liquid crystal layer 113 1 sides of the substrate 111 of the back side one side are provided with reflecting electrode 114, and liquid crystal layer 113 1 sides of the substrate 112 of observer's one side are provided with transparency electrode (not shown).In addition, observer's one side of substrate 112 is provided with polariscope (being typically polarization plate) 115 and λ/4 plates (1/4th wave plate) 116.
This light conductor 20 has polarised light selection layer 22 and the polarised light transform layer 24 that has specific thickness in the normal direction of exit facet 20c.
Polarised light selects layer 22 to make that the light (being designated hereinafter simply as " the 1st polarised light ") of particular polarization penetrates from exit facet 20c selectively among the light of injecting from the plane of incidence (the 1st side) 20a.
In the present embodiment, polarised light selects layer 22 to comprise a plurality of dielectric film 22a that become predetermined angular with respect to exit facet 20c.Dielectric film 22a arranges with predetermined distance (spacing), and is different with the refractive index of its material around.In addition, dielectric film 22a typically thickness be thin dielectric film about the tens of nm of tens of nm～hundred.
Because the refractive index of dielectric film 22a is different with the refractive index of material around, so at the interface of dielectric film 22a and material around, the reflection of light rate has the polarised light dependence.More specifically, the reflectivity height of S polarised light, and the reflectivity of P polarised light is low.Particularly, for the light near the angle incident of Brewster's angle, the reflectivity of P polarised light is almost 0, has only the reflection of S polarised light basically.Therefore, interface in dielectric film 22a and its material around, going up the reflection of light rate height of vibration with the direction (being perpendicular to the direction of paper in Fig. 1) of the repetition direction quadrature of dielectric film 22a, the reflection of light rate of vibrating on the direction different with this specific light (the 1st polarised light) is low.Therefore, in exit facet 20c one side, the 1st polarised light is reflected selectively, penetrates selectively from exit facet 20c the 1st polarised light.
In addition, shown in present embodiment, comprising the polarised light selection layer 22 that becomes a plurality of dielectric film 22a of predetermined angular (tilting) with respect to exit facet 20c with predetermined angular, in fact only will inject the 1st polarised light that comprises the light of light conductor 20 inside from plane of incidence 20a reflexes to exit facet 20c one side to dielectric film 22a, hardly to opposed faces 20d one lateral reflection.Therefore, the 1st polarised light mainly penetrates from exit facet 20c, penetrates from opposed faces 20d hardly.
On the other hand, the light that polarised light transform layer 24 will be different with the polarization direction of above-mentioned the 1st polarised light (for example with the light of the 1st polarised light quadrature, being designated hereinafter simply as " the 2nd polarised light ") is transformed to the 1st polarised light.
In the present embodiment, polarised light transform layer 24 is formed by the transparent material with birefringence.More specifically, polarised light transform layer 24 is transparent resin layers of ejection formation.
The slow axes of the transparent resin layer of ejection formation, the transparent resin layer that promptly forms by jet forming method is inconsistent in the plane that is parallel to exit facet 20c, but exists discrete.Therefore, 2nd polarised light different with the 1st polarised light eliminated polarization by the birefringence that transparent resin layer had in its process of transmitting in polarised light transform layer 24, and its part becomes the 1st polarised light.
With reference to Fig. 2 the transmission situation of light in light conductor 20 inside is described.Among Fig. 2, the two circle expression polarisation of light directions that comprise black circles are perpendicular to paper, and dotted arrow represents that the polarisation of light direction is parallel to paper.
Inject LGP 20 inside from the light that light source 10 penetrates from the 1st side 20a, transmit towards the 2nd side 20b.Among the light of the 2nd side 20b transmission, with the direction of repetition direction (being the normal direction of the plane of incidence 20a here) quadrature of dielectric film 22a on the 1st polarised light that vibrates select layer 22 towards exit facet 20c reflection through polarised light, penetrate from exit facet 20c and go.In addition, among the light of the 2nd side 20b transmission, the 2nd polarised light of polarization direction and the 1st polarised light quadrature selects layer 22 towards exit facet 20c reflection through polarised light after polarised light transform layer 24 is transformed to the 1st polarised light, penetrates from exit facet 20c and goes.In addition, in the present embodiment, polarised light selects layer 22 to comprise a plurality of dielectric film 22a; On the interface of this dielectric film 22a and on every side material, actual glazing is also injected with near the angle beyond the Brewster's angle.Therefore, at this interface, the light beyond strict the 1st polarised light in fact also is reflected; From exit facet 20c, the light beyond strict the 1st polarised light in fact also penetrates.Therefore, so-called " the 1st polarised light being penetrated selectively from exit facet " meaning is " penetrate the 1st polarised light from exit facet and account for leading light ", and might not be to say " only the 1st polarised light is penetrated from exit facet and go ".
The polariscope 115 of reflective liquid crystal display floater 110 is configured to its axis of homology and the polarization direction almost parallel that penetrates the 1st polarised light that goes from exit facet 20c in the present embodiment.Therefore, penetrate the 1st polarised light that goes from lighting device 120 and can be polarized mirror 115 absorptions hardly, but inject liquid crystal layer 113.In addition, it is necessarily parallel that the polarization direction of the 1st polarised light and the axis of homology of polariscope 115 do not need, and also retardation plate can be set between polariscope 115 exit facet 20c, is used for making the polarization direction of the 1st polarised light consistent with the axis of homology of polariscope 115.
As mentioned above, in lighting device 120 of the present invention, light conductor 20 possesses: polarised light is selected layer 22, is used for making the 1st polarised light to penetrate from exit facet 20c selectively; And polarised light transform layer 24, be used for 2nd polarised light different with the 1st polarised light polarization direction is transformed to the 1st polarised light; Therefore, can will penetrate as the light of particular polarization efficiently via the light that plane of incidence 20a injects in the light conductor 20 from light source 10.Therefore, the utilization ratio of light improves.
In addition, in the lighting device 120 of present embodiment, owing to polarised light selection layer 22 in fact only reflexes to exit facet 20c one side with the 1st polarised light, so can suppress owing to the utilization ratio decline of the light that causes to opposed faces 20d one side (observer's one side) reflection of light and the decline of display quality (contrast).
Further, in the lighting device 120 of present embodiment, polarised light transform layer 24 is transparent resin layers of ejection formation.Therefore, be easy to the structure that forms thick polarised light transform layer 24, occupy light conductor 20, can in polarised light transform layer 24, transmit more light, efficiently the 2nd polarised light is transformed to the 1st polarised light than multizone.
For example, the lighting device 120 of present embodiment can followingly be made.
At first, shown in Fig. 3 (a), use that refractive index is 1.49, isotropic polymethyl methacrylate is made the prismatic lens 25 of thickness as 0.2mm.Prismatic lens 25 has the back side 25b that cross sectional shape is wavy surperficial 25a of sawtooth and substantially flat, and back side 25b becomes exit facet 20c later on.Surface 25a is formed with vertical substantially vertical area 25a2 alternate configurations by the tilting zone 25a1 that tilts with respect to back side 25b.
Secondly, shown in Fig. 3 (b), the last refractive index by evaporation thickness 75nm of the tilting zone 25a1 of the surperficial 25a of this prismatic lens 25 is 2.10 ZrO
2Form dielectric film (thin dielectric film) 22a.
Then, shown in Fig. 3 (c), it is that 1.49 clear binder 27 is bonding that this prismatic lens 25 and to use refractive index be 1.49 polymethyl methacrylate by jet forming method formation thickness are utilized refractive index as the transparent resin sheet 26 of 0.8mm.Can obtain having the light conductor 20 that polarised light is selected layer 22 and polarised light transform layer 24 like this.
At the plane of incidence 20a of light conductor 20 side configuration light source (for example cold-cathode tube) 10, around light source 10 configuration reflection parts (for example reflectance coating) 12, thus, finish as shown in Figures 1 and 2 lighting device 120 thereafter.
In the lighting device 120 that Fig. 4 represents to make according to this kind mode from the angle of emergence of the light of exit facet 20c (°) and relative brightness (arbitrary unit; A.u.) relation.In addition, in Fig. 4, in order to compare, the brightness in the lighting device of also having represented in the lump except that utilizing extrinsion pressing formation transparent resin sheet, in kind to make.
As shown in Figure 4, the lighting device of the transparent resin sheet manufacturing that forms by extrinsion pressing than use of the lighting device 120 that uses the transparent resin sheet manufacturing that forms by the jet forming method brightness that more can improve emergent light.This is because in the transparent resin sheet that utilizes extrinsion pressing to form, the 2nd polarised light can not be transformed to the 1st polarised light efficiently; Relative therewith, in the transparent resin sheet 26 that utilizes jet forming method to form, the 2nd polarised light is transformed to the 1st polarised light efficiently.
As everyone knows, the birefringence size that had of the transparent resin layer (for example above-mentioned transparent resin sheet) that uses transparent resin to form is different and different with its forming method.For example, " design of the exploitation of up-to-date optical resin, characteristic and high precision part, forming technique " (publisher: record and narrate in technical information association of Co., Ltd.) the 8th page, with jet forming method, extrinsion pressing, compression forming method and mould forming method is preface, and it is big that birefringence becomes.
Therefore, if use jet forming method, can make the birefringence of transparent resin layer fully become big.Therefore, the transparent resin layer that utilizes jet forming method to form can be transformed to the 1st polarised light with the 2nd polarised light in light conductor 20 internal transmission efficiently as polarised light transform layer 24.
In addition, when using slow axes being parallel to material (for example transparent resin layer of the ejection formation of present embodiment) discrete in the plane of exit facet 20c as polarised light transform layer 24, polarised light transform layer 24 preferably is disposed at opposed faces 20d one side of selecting layer 22 with respect to polarised light as present embodiment.
If polarised light transform layer 24 is configured in opposed faces 20d one side of selecting layer 22 with respect to polarised light, then select layer 22 before going, can not pass polarised light transform layer 24, can not be polarized light transform layer 24 and eliminate polarizations from exit facet 20c ejaculation towards the 1st polarised light of exit facet 20c (reflection) by means of polarised light.
In addition, here, the material of light conductor 20 (material of prismatic lens 25 or transparent resin sheet 26) has used polymethyl methacrylate; But be not limited to this, can use various transparent materials such as Merlon.
In addition, the polarised light of example selects layer 24 to comprise a plurality of dielectric film 22a here; But be not limited to this, go, for example can use to comprise the material that becomes a plurality of dielectric multilayer films of predetermined angular with respect to exit facet 20c as long as the light of particular polarization can be penetrated from exit facet 20c selectively.Utilization ratio and raising display quality in order to improve light preferably use the material that in fact only the light of particular polarization is reflexed to exit facet 20c one side.
(the 2nd embodiment)
The lighting device 220 of embodiments of the present invention is described and possesses the structure of the liquid crystal indicator (image display device) 200 of this lighting device 220 with reference to Fig. 5.In the accompanying drawing afterwards, for the purpose of simplifying the description, use identical quotation mark to represent the structural element that lighting device 120 and liquid crystal indicator 100 with the 1st embodiment have said function in fact, omit its part explanation.
As shown in Figure 5, liquid crystal indicator 200 is the reflection-type liquid-crystal display devices that possess reflective liquid crystal display floater 210, lighting device (front light-source) 220.
Reflective liquid crystal display floater 210 is known reflective liquid crystal display floaters, and for example, it has the same structure of reflective liquid crystal display floater that the liquid crystal indicator 100 with the 1st embodiment had 110.
In lighting device shown in Figure 1 120, polarised light transform layer 24 is transparent resin layers of ejection formation, and its slow axes is inconsistent in the face that is parallel to exit facet 20c, but exists discrete.
Relative therewith, in the lighting device 220 of present embodiment, polarised light transform layer 24 is so-called retardation plates, its slow axes basic identical in the face that is parallel to exit facet 20c (unanimity).Polarised light transform layer 24 as retardation plate, its slow axes and fast axis (typically with the slow axes quadrature) structure is inconsistent with the polarization direction of the 1st polarised light, and the birefringence (straight line birefringence) that 2nd polarised light different with the 1st polarised light had by polarised light transform layer 24 is transformed to the 1st polarised light.As retardation plate is polarised light transform layer 24, can use for example λ/2 plates (1/2nd wave plate).Certainly, be not limited to λ/2 plates, also can use λ/2 plates retardation plate in addition as described later.
With reference to Fig. 6 the transmission situation of light in light conductor 20 inside is described.
Inject LGP 20 inside from the light that light source 10 penetrates from the 1st side 20a, transmit towards the 2nd side 20b.Among the light of the 2nd side 20b transmission, with the direction of repetition direction (being the normal direction of the plane of incidence 20a here) quadrature of dielectric film 22a on the 1st polarised light that vibrates select layer 22 towards exit facet 20c reflection through polarised light, penetrate from exit facet 20c and go.In addition, among the light of the 2nd side 2 0b transmission, the 2nd polarised light of polarization direction and the 1st polarised light quadrature selects layer 22 towards exit facet 20c reflection through polarised light after polarised light transform layer 24 is transformed to the 1st polarised light, penetrates from exit facet 20c.
As mentioned above, in the lighting device 220 of present embodiment, light conductor 20 also possesses: polarised light is selected layer 22, is used for making the 1st polarised light to penetrate from exit facet 20c selectively; And polarised light transform layer 24, be used for 2nd polarised light different with the 1st polarised light polarization direction is transformed to the 1st polarised light; Therefore, can will penetrate as the light of particular polarization efficiently via the light that plane of incidence 20a injects in the light conductor 20 from light source 10.Therefore, the utilization ratio of light improves.
In addition, in the lighting device 220 of present embodiment, because polarised light transform layer 24 is retardation plates, so its slow axes basic identical in the face that is parallel to exit facet 20c (unanimity).Therefore, it is basic identical in the face that is parallel to exit facet 20c that the 2nd polarised light is transformed to the efficient of the 1st polarised light, therefore, is designed to the 1st polarised light easily and penetrates equably from exit facet 20c.
For example, the lighting device 220 of present embodiment can followingly be made.
At first, shown in Fig. 7 (a), use that refractive index is 1.49, isotropic polymethyl methacrylate is made the prismatic lens 25 of thickness as 1.0mm.Prismatic lens 25 has the back side 25b that cross sectional shape is wavy surperficial 25a of sawtooth and substantially flat.Surface 25a is formed with vertical substantially vertical area 25a2 alternate configurations by the tilting zone 25a1 that tilts with respect to back side 25b.
Secondly, shown in Fig. 7 (b), the last refractive index by evaporation thickness 75nm of the tilting zone 25a1 of the surperficial 25a of this prismatic lens 25 is 2.10 ZrO
2Form dielectric film (thin dielectric film) 22a.
Then, shown in Fig. 7 (c), utilizing refractive index is that the surperficial 25a of 29 pairs of these prismatic lenses 25 of transparent resin of 1.49 carries out planarization, simultaneously, pasting refractive index at the back side of prismatic lens 25 25b is λ/2 plates (Nitto Denko Corp's manufacturing) 28 1.51, that be made of ア one ト Application (registration mark).Can obtain having the light conductor 20 that polarised light is selected layer 22 and polarised light transform layer 24 like this.
At the plane of incidence 20a of light conductor 20 side configuration light source (for example cold-cathode tube) 10, around light source 10 configuration reflection parts (for example reflectance coating) 12, thus, finish as Fig. 5 and shown in Figure 6 lighting device 220 thereafter.
In the lighting device 220 that Fig. 8 represents to make according to this kind mode from the angle of emergence of the light of exit facet 20c (°) and relative brightness (arbitrary unit; A.u.) relation.Expression the axial refractive index n of slower rays as shown in Figure 9 in Fig. 8 along λ/2 plates 28
x, along the refractive index n of the fast axis direction of λ/2 plates 28
y, λ/2 plates 28 the refractive index n of thickness direction
z, the polarization direction P of thickness d, visible wavelength λ (not shown), the 1st polarised light of λ/2 plates 28 and λ/2 plates 28 to this brightness of slow axes angulation α when satisfying following the relation.
(n
x-n
y)·d＝270nm
(n
x-n
z)/(n
x-n
y)＝1.0
α＝65°
In addition, in order to compare, in Fig. 8, also represented except not possessing λ/2 plates (retardation plate) brightness in the lighting device with above-mentioned same manufacturing in the lump.
As shown in Figure 8, having as the lighting device 220 of the polarised light transform layer 24 of retardation plate is the brightness that the lighting device of polarised light transform layer more can improve emergent light than not possessing retardation plate.Promptly as can be known: be transformed to the 1st polarised light efficiently by means of polarised light transform layer 24, the 2 polarised lights as retardation plate.
In addition, be not limited to herein example as the specification of the retardation plate of polarised light transform layer 24.The following describes the specification of suitable retardation plate.Specify the refractive index n of slow axes (slow axes that in the face that is parallel to exit facet 20c, has) direction along retardation plate
x, along the refractive index n of fast axis (fast axis that in the face that is parallel to exit facet 20c, the has) direction of retardation plate
y, along the refractive index n of the thickness direction of retardation plate
z, the polarization direction P of thickness d, visible wavelength λ, the 1st polarised light of retardation plate and retardation plate the suitable relation of slow axes angulation α.
At first, Nz=(n is described
x-n
z)/(n
x-n
y)=0 is n
x=n
zThe uniaxiality retardation plate.Represented among Figure 10, Figure 11, Figure 12 and Figure 13 to be transformed to the efficient (ratio) of the 1st polarised light through calculating the result of gained after the 2nd polarised light passes the anisotropic retardation plate of this refractive index with uniaxiality for 2 times.Figure 10 (a), Figure 11 (a), Figure 12 (a) and Figure 13 (a) be the efficient of representing to be transformed to the 1st polarised light by the value that changes α with light the angle of retardation plate internal transmission (°) the chart of relation, Figure 10 (b), Figure 11 (b), Figure 12 (b) and Figure 13 (b) be by the value of change λ represent to be transformed to the efficient of the 1st polarised light and light the angle of retardation plate internal transmission (°) the chart of relation.In addition, the phase difference (n of the retardation plate of Figure 10～shown in Figure 13
x-n
y) d is as shown in table 1.
Table 1
| Nz | (n x-n y)·d | Remarks | |
| Figure 10 (a) and (b) | 0 | 137.5nm | λ/4 plates to the light of λ=550nm |
| Figure 11 (a) and (b) | 0 | 275.0nm | λ/2 plates to the light of λ=550nm |
| Figure 12 (a) and (b) | 0 | 412.5nm | 3 λ/4 plates to the light of λ=550nm |
| Figure 13 (a) and (b) | 0 | 550.0nm | λ plate to the light of λ=550nm |
Here, repeat total reflection and transmit through exit facet 20c and opposed faces 20d, therefore, also be angle more than the θ c with respect to the face inner total reflection angle that is parallel to exit facet 20c at the light of retardation plate internal transmission at the light of light conductor 20 internal transmission.Therefore, delayed of the 2nd polarised light efficient that is transformed to the 1st polarised light can be considered in the scope more than the angle of total reflection θ c.Use when the material of light conductor or retardation plate under the situation of used usually polymethyl methacrylate, Merlon and ア one ト Application transparent resins such as (registration marks), angle of total reflection θ c is about 40 °.
Figure 10 (a) and (b) be that the charts of λ/4 plates as the result under the situation of retardation plate are used in expression.Figure 10 (a) expression is for the conversion efficiency of the light of λ=550nm.By Figure 10 (a) as can be known, by λ/4 plates being configured to for example α=50 °, the 2nd polarised light can be transformed to the 1st polarised light efficiently.Particularly, be transformed to the 1st polarised light at λ/4 intralamellar parts with about 9 one-tenth of the 2nd polarised light of about 60 ° angle transmission.In addition, the conversion efficiency under the situation of Figure 10 (b) expression α=50 °.By Figure 10 (b) as can be known,, this means that color appears in the 1st polarised light that can suppress to go from exit facet 20c ejaculation after the conversion in the 2nd polarised light conversion efficiency almost fixed in the wavelength of visible light scope of λ/4 intralamellar parts with about 60 ° angle transmission.
Figure 11 (a) and (b) be that the charts of λ/2 plates as the result under the situation of retardation plate are used in expression.Figure 11 (a) expression is for the conversion efficiency of the light of λ=550nm.By Figure 11 (a) as can be known, by λ/2 plates being configured to for example α=20 °, the 2nd polarised light can be transformed to the 1st polarised light efficiently.Particularly, be transformed to the 1st polarised light at λ/2 intralamellar parts with about 9 one-tenth of the 2nd polarised light of about 80 ° angle transmission.In addition, the conversion efficiency under the situation of Figure 11 (b) expression α=20 °.By Figure 11 (b) as can be known, at conversion efficiency wavelength of visible light scope in the basically identical of λ/2 intralamellar parts with the 2nd polarised light of about 80 ° angle transmission.
Figure 12 (a) and (b) be that the charts of 3 λ/4 plates as the result under the situation of retardation plate are used in expression.Figure 12 (a) expression is for the conversion efficiency of the light of λ=550nm.By Figure 12 (a) as can be known, by 3 λ/4 plates being configured to for example α=20 °, the 2nd polarised light can be transformed to the 1st polarised light efficiently.Particularly, be transformed to the 1st polarised light at λ/2 intralamellar parts with about 9 one-tenth of the 2nd polarised light of about 45 ° angle transmission.In addition, the conversion efficiency under the situation of Figure 12 (b) expression α=20 °.By Figure 12 (b) as can be known, in conversion efficiency wavelength of visible light scope in the almost fixed of 3 λ/4 intralamellar parts with the 2nd polarised light of about 45 ° angle transmission.
Figure 13 (a) and (b) be that the chart of λ plate as the result under the situation of retardation plate used in expression.Figure 13 (a) expression is for the conversion efficiency of the light of λ=550nm.Conversion efficiency by Figure 13 (a) as can be known,, the 2nd polarised light can be transformed to the 1st polarised light efficiently, more than can reach 9 one-tenth with the angle difference at the light of λ intralamellar part transmission by the λ plate being configured to for example α=10 ° or 40 °～60 °.Yet under the situation of for example α=40 °, by Figure 13 (b) as can be known, the efficient that is transformed to the 1st polarised light significantly changes in the wavelength of visible light scope.Therefore, the light quantity of the 1st polarised light that penetrates from exit facet 20c is different and different with wavelength, color can occur.
Carried out thinking to have at retardation plate under the anisotropic situation of refractive index of uniaxiality after the detailed discussion research the present application people on the basis of The above results, if along the axial refractive index n of the slower rays of retardation plate
x, along the refractive index n of fast axis direction
y, thickness direction refractive index n
z, the polarization direction of thickness d, visible wavelength λ and the 1st polarised light of retardation plate and the slow axes angulation α of retardation plate satisfy the relation of following (1), then the 2nd polarised light can be transformed to the 1st polarised light efficiently.
(n
x-n
z)/(n
x-n
y)0
0＜(n
x-n
y)·d＜λ …(1)
10 °＜α＜30 ° or 40 °＜α＜60 °
Particularly, if satisfy the relation of following (2), then the 2nd polarised light efficient that is transformed to the 1st polarised light changes with the wavelength in the visible wavelength range hardly, therefore, has suppressed the appearance of color.
(n
x-n
z)/(n
x-n
y)0
(n
x-n
y)·d＝λ/2 …(2)
10°＜α＜30°
Nz=(n then is described
x-n
z)/(n
x-n
y)=1 is n
y=n
zThe uniaxiality retardation plate.Represented among Figure 14, Figure 15, Figure 16, Figure 17 and Figure 18 to be transformed to the efficient (ratio) of the 1st polarised light through calculating the result of gained after the 2nd polarised light passes the anisotropic retardation plate of this refractive index with uniaxiality for 2 times.In addition, the phase difference (n of the retardation plate of Figure 14～shown in Figure 180
x-n
y) d is as shown in table 2.
Table 2
| Nz | (n x-n y)·d | Remarks | |
| Figure 14 | 1 | 137.5nm | λ/4 plates to the light of λ=550nm |
| Figure 15 (a) and (b) | 1 | 275.0nm | λ/2 plates to the light of λ=550nm |
| Figure 16 (a) and (b) | 1 | 412.5nm | 3 λ/4 plates to the light of λ=550nm |
| Figure 17 (a) and (b) | 1 | 550.0nm | λ plate to the light of λ=550nm |
| Figure 18 (a) and (b) | 1 | 687.5nm | 5 λ/4 plates to the light of λ=550nm |
Figure 14 be illustrated in use λ/4 plates as under the situation of retardation plate for the chart of the conversion efficiency of the light of λ=550nm.As shown in Figure 14, though use λ/4 plates the 2nd polarised light can be transformed to the 1st polarised light, the conversion efficiency maximum only is about 7 one-tenth.
Figure 15 (a) and (b) be that the charts of λ/2 plates as the result under the situation of retardation plate are used in expression.Conversion efficiency under the situation of Figure 15 (a) expression λ=550nm.Its conversion efficiency by Figure 15 (a) as can be known,, just the 2nd polarised light can be transformed to the 1st polarised light efficiently, more than can reach 9 one-tenth with the transmission of angle difference of light by λ/2 plates being configured to for example α=30 °～70 °.In addition, the conversion efficiency under the situation of Figure 15 (b) expression α=70 °.By Figure 15 (b) as can be known, conversion efficiency in the wavelength of visible light scope basically not with wavelength change.
Figure 16 (a) and (b) be that the charts of 3 λ/4 plates as the result under the situation of retardation plate are used in expression.Figure 16 (a) is illustrated in the conversion efficiency under the situation of λ=550nm.By Figure 16 (a) as can be known, by 3 λ/4 plates being configured to for example α=80 °, the 2nd polarised light can be transformed to the 1st polarised light efficiently.Particularly, be transformed to the 1st polarised light at 3 λ/4 intralamellar parts more than 9 one-tenth with the 2nd polarised light of about 60 ° angle transmission.In addition, Figure 16 (b) is illustrated in the conversion efficiency under the situation of α=80 °.By Figure 16 (b) as can be known, in conversion efficiency wavelength of visible light scope in the almost fixed of 3 λ/4 intralamellar parts with the 2nd polarised light of about 60 ° angle transmission.
Figure 17 (a) and (b) be that the chart of λ plate as the result under the situation of retardation plate used in expression.Figure 17 (a) is illustrated in the conversion efficiency under the situation of λ=550nm.Conversion efficiency by Figure 17 (a) as can be known,, the 2nd polarised light can be transformed to the 1st polarised light efficiently, more than can reach 9 one-tenth with the angle difference at the light of λ intralamellar part transmission by the λ plate being configured to for example α=40 °～50 ° or 80 °.In addition, the conversion efficiency under the situation of Figure 17 (b) expression α=80 °.By Figure 17 (b) as can be known, in conversion efficiency wavelength of visible light scope in the almost fixed of λ intralamellar part with the 2nd polarised light of about 65 ° angle transmission.
Figure 18 (a) and (b) be that the charts of 5 λ/4 plates as the result under the situation of retardation plate are used in expression.Figure 18 (a) is illustrated in the conversion efficiency under the situation of λ=550nm.By Figure 18 (a) as can be known,, just the 2nd polarised light can be transformed to the 1st polarised light efficiently by 5 λ/4 plates being configured to for example α=30 °～60 °, its conversion efficiency with light more than the transmission of angle difference of 5 λ/4 intralamellar parts can reach 9 one-tenth.Yet under the situation of for example α=60 °, by Figure 18 (b) as can be known, the efficient that is transformed to the 1st polarised light significantly changes in the wavelength of visible light scope.Therefore, the light quantity of the 1st polarised light that penetrates from exit facet 20c is different and different with wavelength, color can occur.
Carried out thinking to have at retardation plate under the anisotropic situation of refractive index of uniaxiality after the detailed discussion research the present application people on the basis of The above results, if along the axial refractive index n of the slower rays of retardation plate
x, along the refractive index n of fast axis direction
y, thickness direction refractive index n
z, the polarization direction of thickness d, visible wavelength λ and the 1st polarised light of retardation plate and the slow axes angulation α of retardation plate satisfy the relation of following (3), also the 2nd polarised light can be transformed to the 1st polarised light efficiently.
(n
x-n
z)/(n
x-n
y)1
λ/4＜(n
x-n
y)·d＜5λ/4 …(3)
20°＜α＜90°
Particularly, if satisfy the relation of following (4), then the 2nd polarised light efficient that is transformed to the 1st polarised light does not change with the wavelength in the visible wavelength range basically, therefore, has suppressed the appearance of color.
(n
x-n
z)/(n
x-n
y)1
(n
x-n
y)·d＝λ/2 …(4)
20°＜α＜80°
So far the retardation plate at uniaxiality is illustrated, if use the retardation plate of uniaxiality, as Figure 10～shown in Figure 180, the transmission of angle scope that conversion efficiency is high as can be known is not enough greatly.
The anisotropic retardation plate of refractive index that the present application people has biaxiality by use, discovery can enlarge the high transmission of angle scope of conversion efficiency.Described in detail below.
Particularly, at 0＜Nz=(n
x-n
z)/(n
x-n
y)＜1 is n
x≠ n
zAnd n
y≠ n
zThe biaxiality retardation plate describe.Represented among Figure 19, Figure 20, Figure 21, Figure 22, Figure 23 and Figure 24 to be transformed to the efficient (ratio) of the 1st polarised light through calculating the result of gained after the 2nd polarised light passes the anisotropic retardation plate of this refractive index with this biaxiality for 2 times.In addition, the phase difference (n of the retardation plate of Figure 19～shown in Figure 24
x-n
y) d is as shown in table 3.
Table 3
| Nz | (n x-n y)·d | Remarks | |
| Figure 19 | 0.5 | 137.5nm | λ/4 plates to the light of λ=550nm |
| Figure 20 | 0.9 | 275.0nm | λ/2 plates to the light of λ=550nm |
| Figure 21 (a) and (b) | 0.8 | 275.0nm | λ/2 plates to the light of λ=550nm |
| Figure 22 (a) and (b) | 0.7 | 275.0nm | λ/2 plates to the light of λ=550nm |
| Figure 23 | 0.6 | 275.0nm | λ/2 plates to the light of λ=550nm |
| Figure 24 (a) and (b) | 0.2 | 412.5nm | 3 λ/4 plates to the light of λ=550nm |
Figure 19 be illustrated in λ/4 plates of using Nz=0.5 as under the situation of retardation plate for the chart of the conversion efficiency of the light of λ=550nm.As shown in Figure 19, though use λ/4 plates of Nz=0.5 the 2nd polarised light can be transformed to the 1st polarised light, the conversion efficiency maximum only is about 7 one-tenth.In addition, the present application people for λ/4 plates of 0＜Nz＜1, can't obtain the high conversion efficiency more than 9 one-tenth inquiring into the discovery of research back in the big angular range of transmission of angle.
Figure 20 be illustrated in λ/2 plates of using Nz=0.9 as under the situation of retardation plate for the chart of the conversion efficiency of the light of λ=550nm.Its conversion efficiency as shown in Figure 20,, the 2nd polarised light can be transformed to the 1st polarised light efficiently, more than can reach 9 one-tenth with the transmission of angle difference of light by using λ/2 plates of Nz=0.9; But the transmission of angle scope that conversion efficiency is high is big inadequately.
Figure 21 (a) and (b) be that the charts of λ/2 plates of Nz=0.8 as the result under the situation of retardation plate are used in expression.Figure 21 (a) is illustrated in the conversion efficiency under the situation of λ=550nm.By Figure 21 (a) as can be known, for example be configured to α=70 °, just the 2nd polarised light can be transformed to the 1st polarised light efficiently, be about more than 40 °～80 ° inner conversion efficient on a large scale can reach 9 one-tenth at transmission of angle by λ/2 plates with Nz=0.8.In addition, the conversion efficiency under the situation of Figure 21 (b) expression α=70 °.By Figure 21 (b) as can be known, be configured at λ/2 plates of for example Nz=0.8 under the situation of α=70 °, conversion efficiency is almost fixed in the wavelength of visible light scope.
Figure 22 (a) and (b) be that the charts of λ/2 plates of Nz=0.7 as the result under the situation of retardation plate are used in expression.Figure 22 (a) is illustrated in the conversion efficiency under the situation of λ=550nm.By Figure 22 (a) as can be known, for example be configured to α=70 °, just the 2nd polarised light can be transformed to the 1st polarised light efficiently, be about more than 40 °～70 ° inner conversion efficient on a large scale can reach 9 one-tenth at transmission of angle by λ/2 plates with Nz=0.7.In addition, the conversion efficiency under the situation of Figure 22 (b) expression α=70 °.By Figure 22 (b) as can be known, be configured at λ/2 plates of for example Nz=0.7 under the situation of α=70 °, conversion efficiency is almost fixed in the wavelength of visible light scope.
Figure 23 be illustrated in λ/2 plates of using Nz=0.6 as under the situation of retardation plate for the chart of the conversion efficiency of the light of λ=550nm.Its conversion efficiency as shown in Figure 23,, the 2nd polarised light can be transformed to the 1st polarised light efficiently, more than can reach 9 one-tenth with the transmission of angle difference of light by using λ/2 plates of Nz=0.6; But the transmission of angle scope that conversion efficiency is high is big inadequately.
Figure 24 (a) and (b) be that the charts of 3 λ/4 plates of Nz=0.2 as the result under the situation of retardation plate are used in expression.Figure 24 (a) is illustrated in the conversion efficiency under the situation of λ=550nm.By Figure 24 (a) as can be known, for example be configured to α=20 °, just the 2nd polarised light can be transformed to the 1st polarised light efficiently, be about more than 50 °～70 ° inner conversion efficient on a large scale can reach 9 one-tenth at transmission of angle by 3 λ/4 plates with Nz=0.2.Yet under the situation of 3 λ/4 plates that use Nz=0.2, for example during α=20 °, by Figure 24 (b) as can be known, the efficient that is transformed to the 1st polarised light significantly changes in the wavelength of visible light scope.Therefore, the light quantity of the 1st polarised light that penetrates from exit facet 20c is different and different with wavelength, color can occur.
Carried out thinking to have at retardation plate under the anisotropic situation of refractive index of biaxiality after the detailed discussion research the present application people on the basis of The above results, if along the axial refractive index n of the slower rays of retardation plate
x, along the refractive index n of fast axis direction
y, thickness direction refractive index n
z, the polarization direction of thickness d, visible wavelength λ and the 1st polarised light of retardation plate and the slow axes angulation α of retardation plate satisfy the relation of following (5), also the 2nd polarised light can be transformed to the 1st polarised light efficiently in big angular range (scope of transmission of angle).
0.6＜(n
x-n
z)/(n
x-n
y)＜0.9
λ/4＜(n
x-n
y)·d＜3λ/4 …(5)
60°＜α＜80°
Particularly, if satisfy the relation of following (6), then the 2nd polarised light efficient that is transformed to the 1st polarised light does not change with the wavelength in the visible wavelength range basically, therefore, has suppressed the appearance of color.
0.6＜(n
x-n
z)/(n
x-n
y)＜0.9
(n
x-n
y)·d＝λ/2 …(6)
60°＜α＜80°
In addition, in the present embodiment, be disposed at opposed faces 20d one side of selecting layer 22 with respect to polarised light as the polarised light transform layer 24 of retardation plate; Certainly be not limited to this, also can be configured in exit facet 20c one side.
As present embodiment, at polarised light transform layer 24 is under the situation of retardation plate, the slow axes of polarised light transform layer 24 is basically identical in the face that is parallel to exit facet 20c, therefore, if polarised light transform layer 24 (retardation plate) selects layer 22 to be configured in exit facet one side with respect to polarised light, then select layer 22 after the 1st polarization polarized state of light (for example polarization direction) of exit facet 20c can be controlled by this retardation plate, to penetrate from exit facet 20c through polarised light.
(the 3rd embodiment)
The lighting device 320 of embodiments of the present invention is described and possesses the structure of the liquid crystal indicator (image display device) 300 of this lighting device 320 with reference to Figure 25.
As shown in figure 25, liquid crystal indicator 300 is the reflection-type liquid-crystal display devices that possess reflective liquid crystal display floater 310, lighting device (front light-source) 320.
Reflective liquid crystal display floater 310 is known reflective liquid crystal display floaters, and for example, it has the same structure of reflective liquid crystal display floater that the liquid crystal indicator 100 with the 1st embodiment had 110.
The light conductor 20 of lighting device 320 possesses the polarised light transform layer 24 that is configured near the polarised light selection layer 22 of exit facet 20c and is configured in opposed faces 20d one side.In the present embodiment, polarised light transform layer 24 is retardation plates.
The dielectric film that polarised light is selected layer 22 to comprise to tilt with predetermined angular with respect to exit facet 20c (below be also referred to as " inclination dielectric film ") 22a and the dielectric film that is roughly parallel to exit facet 20c (below be also referred to as " parallel dielectric film ") 22b.
Relative therewith, parallel dielectric film 22b disposes than comparatively dense near the plane of incidence (the 1st side) 20a, disposes more sparsely near the 2nd side 20b.That is, inclination dielectric film 22a is far away more apart from plane of incidence 20a, and its configuration is sparse more.
With reference to Figure 26 the transmission situation of light in light conductor 20 inside is described.
Inject LGP 20 inside from the light that light source 10 penetrates from the 1st side 20a, transmit towards the 2nd side 20b.Among the light of the 2nd side 20b transmission, with the direction of repetition direction (being the normal direction of the plane of incidence 20a here) quadrature of dielectric film 22a on the 1st polarised light that the vibrates inclination dielectric film 22a that selects to comprise in the layer 22 through polarised light towards exit facet 20c reflection, penetrate from exit facet 20c.
In addition, among the light of the 2nd side 20b transmission, the 2nd polarised light of polarization direction and the 1st polarised light quadrature selects layer 22 towards exit facet 20c reflection through polarised light after polarised light transform layer 24 is transformed to the 1st polarised light, penetrates from exit facet 20c.
In addition, though the part towards the light of the 2nd side 20b transmission reflexes to opposed faces 20d one side through parallel dielectric film 22b, but, therefore, do not penetrate from opposed faces 20d because its major part reflects with the angle more than the critical angle (promptly not satisfying the angle of total reflection condition) at opposed faces 20d.
As mentioned above, in the lighting device 320 of present embodiment, light conductor 20 possesses: polarised light is selected layer 22, is used for making the 1st polarised light to penetrate from exit facet 20c selectively; And polarised light transform layer 24, be used for 2nd polarised light different with the 1st polarised light polarization direction is transformed to the 1st polarised light; Therefore, the light of injecting from light source 10 in the light conductor 20 can be penetrated as the light of particular polarization efficiently.Therefore, the utilization ratio of light improves.
In addition, in lighting device 320, because polarised light transform layer 24 is retardation plates, so its slow axes basic identical in the face that is parallel to exit facet 20c (unanimity).Therefore, it is basic identical in the face that is parallel to exit facet 20c that the 2nd polarised light is transformed to the efficient of the 1st polarised light, therefore, is designed to the 1st polarised light easily and penetrates equably from exit facet 20c.
Further, in lighting device 320, because polarised light selects the inclination dielectric film 22a that comprises in the layer 22 intensive more apart from its configuration of plane of incidence 20a (promptly far away more apart from light source 10) far away more, therefore as shown in figure 27, can further improve from the uniformity of the 1st polarization light intensity of exit facet 20c ejaculation.
Relative therewith, in the lighting device 220 shown in Figure 5 (or lighting device 120 shown in Figure 1), the dielectric film 22a that tilts with predetermined angular with respect to exit facet 20c is not subjected to the influence of the distance of itself and plane of incidence 20a, form with same ratio, therefore, as shown in figure 28, the 1st polarised light is gone by ejaculation mostly near plane of incidence 20a, far away more apart from plane of incidence 20a, the 1st polarised light of ejaculation is few more.Therefore, the uniformity of light that penetrates from exit facet 20a can reduce.
For example, the lighting device 320 of present embodiment can followingly be made.
At first, shown in Figure 29 (a), use that refractive index is 1.49, isotropic polymethyl methacrylate is made the prismatic lens 25 of thickness as 1.0mm.Prismatic lens 25 has the back side 25b that cross sectional shape is the wavy interarea of sawtooth (surface) 25a and substantially flat.Interarea 25a has: a plurality of inclined planes (tilting zone) 25a1 that tilts with respect to back side 25b, with a plurality of vertical planes (vertical area) 25a2 of back side 25b approximate vertical, with a plurality of parallel surfaces (parallel zone) 25a3 of back side 25b almost parallel.In addition, a plurality of inclined plane 25a1 are configured to from an end of prismatic lens 25 more and more intensive towards the other end (far away more apart from the side that became plane of incidence 20a afterwards).
Secondly, shown in Figure 29 (b), the last refractive index by evaporation thickness 65nm of the inclined plane 25a1 of the interarea 25a of this prismatic lens 25 is 2.3 TiO
2Form dielectric film (thin dielectric film) 22a.At this moment, also form dielectric film 22b on the parallel surface 25a3 of the interarea 25a of prismatic lens 25.In addition, to schematically show dielectric substance (be TiO to the arrow among Figure 29 (b) here
2) the evaporation situation.
Then, shown in Figure 29 (c), utilization is that the interarea 25a of 29 pairs of prismatic lenses 25 of transparent resin layer of constituting of 1.49 transparent resin material carries out planarization by refractive index, simultaneously, paste λ/2 plates (Nitto Denko Corp's manufacturings) 28 that refractive index is a uniaxiality 1.51, that be made of ア one ト Application (registration mark) at the back side of prismatic lens 25 25b, can have polarised light thus and select layers 22 and the light conductor 30 of polarised light transform layer 24.
At the plane of incidence 20a of light conductor 20 side configuration light source (for example cold-cathode tube) 10, around light source 10 configuration reflection parts (for example reflectance coating) 12, thus, finish as Figure 25 and shown in Figure 26 lighting device 320 thereafter.
According to this kind mode, the structure of the light conductor 20 in the lighting device 320 comprises: the 1st parts (prismatic lens 25) have the interarea 25a that comprises a plurality of inclined plane 25a1 and a plurality of parallel surface 25a3; And the 2nd parts (transparent resin layer 29), be arranged on interarea 25a and go up interarea 25a planarization; On a plurality of inclined plane 25a1, form dielectric film 22a.It is far away more sparse more by a plurality of parallel surface 25a3 are configured to apart from plane of incidence 20a, a plurality of inclined plane 25a1 can be configured to far away more intensively more, can easily realize that dielectric film 22a is apart from plane of incidence 20a intensive more configuration structure far away more apart from plane of incidence 20a.In the fabrication stage, even adopt the operation that on parallel surface 25a3, also forms dielectric film 22b, since the parallel dielectric film 22b that forms on the parallel surface 25a3 not can with the light of transmission light conductor 20 in from the such angle of opposed faces 20d ejaculation to opposed faces 20d one lateral reflection, so can not produce the utilization ratio of light or the decline of display quality.
In addition, be that to select near the situation that layer 22 is disposed at the exit facet 20c, polarised light transform layer 24 is disposed at opposed faces 20d one side with polarised light be example in the present embodiment; But polarised light selects the configuration of layer 22 and polarised light transform layer 24 to be not limited to this.For example, both polarised light can be selected layer 22 be disposed near the opposed faces 20d, also polarised light transform layer 24 can be disposed at exit facet 20c one side.
Yet, in the time of near polarised light selection layer 22 is configured in exit facet 20c, preferably be configured to such polarised light selection layer 22 ratio polarization light transform layer 24 more close exit facet 20c one sides shown in Figure 30 (b), rather than be configured to such polarised light transform layer 24 ratio polarization light selection layer 22 more close exit facet 20c one side shown in Figure 30 (a).
The light conductor 20 of present embodiment not only has the dielectric film 22a with respect to exit facet 20c inclination, and has a dielectric film 22b that is roughly parallel to exit facet 20c, therefore, part at the light of light conductor 20 internal transmission is injected parallel dielectric film 22b with the big incidence angle that departs from Brewster's angle, and the 2nd polarised light is reflected by parallel dielectric film 22b.
Therefore, shown in Figure 30 (a), if polarised light transform layer 24 is configured in the position that ratio polarization light is selected layer 22 more close exit facet 20c one side, then the 2nd polarised light is not easy to arrive polarised light transform layer 24, and the efficient that is transformed to the 1st polarised light can reduce.Relative therewith, as Figure 30 (b) if shown in polarised light select layer 22 to be positioned at the position of ratio polarization light transform layer 24 more close exit facet 20c one sides, then, therefore can suitably carry out of the conversion of the 2nd polarised light to the 1st polarised light because the 2nd polarised light can not be subjected to the interference of parallel dielectric film 22b to the incident of polarised light transform layer 24.
Figure 31 be illustrated in be disposed at as λ/2 plates 28 of polarised light transform layer 24 in the lighting device 320 (structure of Figure 30 (b)) of opposed faces 28d one side the angle of emergence from the light of exit facet 20c (°) with relative brightness (arbitrary unit; A.u.) relation.In addition, in Figure 31 expression with reference to the brightness of such lighting device of making 320 of Figure 29 explanation.In addition, expression the axial refractive index n of slower rays shown in figure 32 in Figure 31 along λ/2 plates 28
x, along the refractive index n of the fast axis direction of λ/2 plates 28
y, λ/2 plates 28 the refractive index n of thickness direction
z, the polarization direction P of thickness d, visible wavelength λ (not shown), the 1st polarised light of λ/2 plates 28 and λ/2 plates 28 to this brightness of slow axes angulation α when satisfying following the relation.
(n
x-n
y)·d＝270nm
(n
x-n
z)/(n
x-n
y)＝1.0
α＝70°
In addition, for comparing, in Figure 31, also represented λ/2 plates (retardation plate) 28 are disposed at the brightness of the lighting device (structure of Figure 30 (a)) of exit facet 20c one side of light conductor 20 in the lump.
As shown in Figure 31, possess the brightness height of the lighting device 320 of polarised light transform layer 24 in the opposed faces 20d of light conductor 20 side than the emergent light of the lighting device that possesses polarised light transform layer 24 in the exit facet 20c of light conductor 20 side.That is, the 2nd polarised light be transformed to the 1st polarised light efficient with the allocation position of polarised light transform layer 24 difference.Therefore, when the polarised light that comprises parallel dielectric film 22b selected layer 22 to be disposed near exit facet 30c, shown in Figure 30 (b), polarised light selected layer 22 preferably in the position of ratio polarization light transform layer 24 more close exit facet 20c one sides.
In addition, according to same reason, in the time of near polarised light selection layer 22 is configured in opposed faces 20c, preferably shown in Figure 33 (b), select layer 22 to be configured to ratio polarization light transform layer 24 more close opposed faces 20d one sides polarised light like that, rather than shown in Figure 33 (a), like that polarised light transform layer 24 is configured to ratio polarization light selection layer 22 more close opposed faces 20d one side.
Shown in Figure 33 (a), if polarised light transform layer 24 ratio polarization light are selected layer 22 more close opposed faces 20d one side, then because the 2nd polarised light is reflected by parallel dielectric film 22b, so the 2nd polarised light is not easy to arrive polarised light transform layer 24, the efficient that is transformed to the 1st polarised light will descend.Relative therewith, as Figure 33 (b) if shown in polarised light select layer 22 to be positioned at the position of ratio polarization light transform layer 24 more close opposed faces 20d one sides, then, therefore can suitably carry out of the conversion of the 2nd polarised light to the 1st polarised light because the 2nd polarised light can not be subjected to the interference of parallel dielectric film 22b to the incident of polarised light transform layer 24.
In addition, near polarised light selection layer 22 is disposed at exit facet 20c, and when polarised light is selected more close exit facet 20c one side of layer 22 ratio polarization light transform layer 24, preferably shown in Figure 34 (b), parallel dielectric film 22b is configured to position than more close exit facet 20c one side of inclination dielectric film 22a, promptly, the parallel surface 25a3 of prismatic lens 25 is than the position of more close exit facet 20c one side of inclined plane 25a1, rather than parallel dielectric film 22b is configured to the position than more close opposed faces 20d one side of inclination dielectric film 22a shown in Figure 34 (a).
Shown in Figure 34 (a), if parallel dielectric film 22b is than the position of more close opposed faces 20d one side of inclination dielectric film 22a, then the part at the light of light conductor 20 internal transmission reflects through parallel dielectric film 22b, thus, light becomes and is not easy to arrive inclination dielectric film 22a, so the 1st polarised light is difficult to penetrate from exit facet 20c.Relative therewith, shown in Figure 34 (b), if parallel dielectric film 22b is than more close exit facet 20c one side of inclination dielectric film 22a, then the light in light conductor 20 internal transmission can directly arrive or arrival inclination dielectric film 22a after parallel dielectric film 22b reflection, therefore, parallel dielectric film 22b can not influence light arrival inclination dielectric film 22a.Therefore, the 1st polarised light is suitably penetrated from exit facet 20c.
In addition, according to same reason, near polarised light selection layer 22 is disposed at opposed faces 20d, and when polarised light is selected more close opposed faces 20d one side of layer 22 ratio polarization light transform layer 24, preferably shown in Figure 35 (b), parallel dielectric film 22b is configured to position than more close opposed faces 20d one side of inclination dielectric film 22a, promptly, the parallel surface 25a3 of prismatic lens 25 is than the position of more close opposed faces 20d one side of inclined plane 25a1, rather than parallel dielectric film 22b is configured to the position than more close exit facet 20d one side of inclination dielectric film 22a shown in Figure 35 (a).
Shown in Figure 35 (a), if parallel dielectric film 22b is than the position of more close exit facet 20c one side of inclination dielectric film 22a, then the part at the light of light conductor 20 internal transmission reflects through parallel dielectric film 22b, thus, light becomes and is not easy to arrive inclination dielectric film 22a, therefore, the 1st polarised light is difficult to penetrate from exit facet 20c.Relative therewith, shown in Figure 35 (b), if parallel dielectric film 22b is than more close opposed faces 20d one side of inclination dielectric film 22a, then the light in light conductor 20 internal transmission can directly arrive or arrival inclination dielectric film 22a after parallel dielectric film 22b reflection, therefore, parallel dielectric film 22b can not influence light arrival inclination dielectric film 22a.Therefore, the 1st polarised light is suitably penetrated from exit facet 20c.
In addition, in above-mentioned embodiment 1～3, be example with the reflection-type liquid-crystal display device 100,200,300 that possesses as the lighting device 120,220,320 of front light-source; But the present invention is not limited to this, also is applicable to the transmissive liquid crystal display device that has as the lighting device of backlight.
(the 4th embodiment)
The lighting device 420 of embodiments of the present invention is described and possesses the structure of the liquid crystal indicator (image display device) 400 of this lighting device 420 with reference to Figure 36.
As shown in figure 36, liquid crystal indicator 400 is the transmissive liquid crystal display devices that possess transmission-type liquid crystal display floater 410, lighting device (backlight) 420.
Transmission-type liquid crystal display floater 410 is known transmission-type liquid crystal display floaters, and here, it has a pair of substrate (for example glass substrate) 411 and 412 and be arranged on liquid crystal layer 413 between them.Substrate 411 and 412 413 1 sides of liquid crystal layer separately are provided with transparency electrode (not shown), and observer's one side of substrate 411 and lighting device 420 1 sides of substrate 412 are provided with polariscope (being typically polarization plate) 415a and 415b.
Figure 37 represent in the lighting device 420 from the angle of emergence of the light of exit facet 20c (°) and relative brightness (arbitrary unit; A.u.) relation.In addition, expression the axial refractive index n of slower rays as shown in figure 38 in Figure 37 along biaxiality λ/2 plates 28
x, along the refractive index n of the fast axis direction of biaxiality λ/2 plates 28
y, biaxiality λ/2 plates 28 the refractive index n of thickness direction
z, the polarization direction P of thickness d, visible wavelength λ (not shown), the 1st polarised light of biaxiality λ/2 plates 28 and biaxiality λ/2 plates 28 to this brightness of slow axes angulation α when satisfying following the relation.
(n
x-n
y)·d＝270nm
(n
x-n
z)/(n
x-n
y)＝0.8
α＝70°
In addition, in order to compare, in Figure 37, also represented to be used as of the brightness of λ/2 plates (retardation plate) of polarised light transform layer 24 in the lump for the lighting device 320 of the 3rd embodiment of uniaxiality.
As shown in Figure 37, has the brightness that the lighting device 420 of biaxiality λ/2 plates as polarised light transform layer 24 more can improve emergent light than the lighting device 320 with uniaxiality λ/2 plates as polarised light transform layer 24.That is, be transformed to the 1st polarised light efficiently by means of polarised light transform layer 24, the 2 polarised lights as biaxiality λ/2 plates.
In addition, in the lighting device 420 of present embodiment, can also can dispose light light diffusing member (for example optical diffusion film) at the opposed faces 20d of light conductor 20 side configuration reflection part (for example reflectance coating) in the exit facet 20c of light conductor 20 side.
In addition, in the present embodiment, be example as the transmissive liquid crystal display device 400 of backlight to possess lighting device 420; But also can be with the front light-source of lighting device 420 as reflection-type liquid-crystal display device.
(the 5th embodiment)
The lighting device 520 of embodiments of the present invention is described and possesses the structure of the liquid crystal indicator (image display device) 500 of this lighting device 520 with reference to Figure 39.
As shown in figure 39, liquid crystal indicator 500 is the reflection-type liquid-crystal display devices that possess reflective liquid crystal display floater 510, lighting device (front light-source) 520.
Reflective liquid crystal display floater 510 is known reflective liquid crystal display floaters, and for example, it has the same structure of reflective liquid crystal display floater that the liquid crystal indicator 100 with the 1st embodiment had 110.
For example, the lighting device 520 of present embodiment can followingly be made.
At first, shown in Figure 40 (a), be to be that 1.51 transparent resin 29 forms prism with refractive index on the retardation plate 28 1.51, that constitute by ア one ト Application (registration mark) in refractive index, making thickness is the prismatic lens 25 ' of 0.2mm.Prismatic lens 25 ' has the back side 25b ' that cross sectional shape is the wavy interarea of sawtooth (surface) 25a ' and substantially flat.Interarea 25a ' has inclined plane (tilting zone) 25a1 ', vertical plane (vertical area) 25a2 ' of approximate vertical, parallel surface (parallel zone) 25a3 ' of almost parallel with respect to back side 25b ' inclination; Inclined plane 25a1 ' is configured to from an end of prismatic lens 25 ' more and more intensive towards the other end (far away more apart from the side that became plane of incidence 20a afterwards).
Secondly, shown in Figure 40 (b), the last refractive index by evaporation thickness 65nm of the inclined plane 25a1 ' of the interarea 25a ' of this prismatic lens 25 ' is 2.3 TiO
2Form dielectric film (thin dielectric film) 22a.In addition, at this moment, also form dielectric film 22b on the parallel surface 25a3 ' of interarea 25a '.
Then, shown in Figure 40 (c), utilizing refractive index is that the interarea 25a ' of 29 pairs of prismatic lenses 25 ' of transparent resin of 1.51 carries out planarization, simultaneously, pasting the thickness that is formed with above-mentioned transparent input unit (touch panel) 530 at the back side of prismatic lens 25 ' 25b ' is the transparency carrier (for example glass substrate) 26 of 0.7mm.
At the plane of incidence 20a of light conductor 20A one side configuration light source (for example cold-cathode tube) 10, around light source 10 configuration reflection parts (for example reflectance coating) 12, thus, finish as shown in figure 39 lighting device 520 thereafter.
In the reflection-type liquid-crystal display device 500 of present embodiment,, therefore, need not to increase too many thickness and get final product the additional input function owing to become one as light conductor 20A and the transparent input unit 530 of the lighting device 520 of front light-source.
(the 6th embodiment)
The lighting device 620 of embodiments of the present invention is described and possesses the structure of the liquid crystal indicator (image display device) 600 of this lighting device 620 with reference to Figure 41.
As shown in figure 41, liquid crystal indicator 600 is the transmissive liquid crystal display devices that possess transmission-type liquid crystal display floater 610, lighting device (backlight) 620.
Transmission-type liquid crystal display floater 610 has the roughly the same structure of transmission-type liquid crystal display floater that the liquid crystal indicator 400 with the 4th embodiment had 410.Yet transmission-type liquid crystal display floater 610 is not that polariscope is set on substrate 412, selects layer 22 and polarised light transform layer 24 but polarised light is set, and is in this, different with above-mentioned transmission-type liquid crystal display floater 410.
In addition, the polarised light of present embodiment is selected layer 22 and polarised light transform layer 24 to have with the polarised light shown in Figure 33 (b) and Figure 35 (b) and is selected layers 22 and the roughly the same structure of polarised light transform layer 24, but be configured in transmission-type liquid crystal display floater 610 on substrate 412, different in this.
Like this, in the present embodiment, substrate 412, polarised light selection layer 22, polarised light transform layer 24 have constituted the light conductor 20B of lighting device 620, the double substrate of doing transmission-type liquid crystal display floater 410 of light conductor 20B.
For example, the lighting device 620 of present embodiment can followingly be made.
At first, shown in Figure 42 (a), be to be that 1.53 transparent resin 29 forms prism with refractive index on the retardation plate 28 1.53, that constitute by ゼ オ ノ ア (registration mark) in refractive index, making thickness is the prismatic lens 25 of 0.2mm ".Prismatic lens 25 " to have cross sectional shape be the wavy interarea of sawtooth (surface) 25a " and the back side 25b of substantially flat ".Interarea 25a " have with respect to back side 25b " inclined plane (tilting zone) 25a1 that tilts ", vertical plane (vertical area) 25a2 of approximate vertical ", parallel surface (parallel zone) 25a3 of almost parallel "; Inclined plane 25a1 " be configured to from prismatic lens 25 " an end more and more intensive towards the other end (it is far away more that distance became the side of plane of incidence 20a afterwards).
Secondly, shown in Figure 42 (b), this prismatic lens 25 " interarea 25a " inclined plane 25a1 " to go up refractive index by evaporation thickness 65nm be 2.3 TiO
2Form dielectric film (thin dielectric film) 22a.In addition, at this moment, interarea 25a " parallel surface 25a3 " on also form dielectric film 22b.
Then, shown in Figure 42 (c), utilizing refractive index is 29 pairs of prismatic lenses 25 of transparent resin of 1.53 " interarea 25a " carry out planarization, simultaneously, with prismatic lens 25 " back side 25b " paste with the substrate 412 of transmission-type liquid crystal display floater 610.
At the plane of incidence 20a of light conductor 20B one side configuration light source (for example cold-cathode tube) 10, around light source 10 configuration reflection parts (for example reflectance coating) 12, thus, finish as shown in figure 41 lighting device 620 thereafter.
In the transmissive liquid crystal display device 600 of present embodiment, the double substrate of doing transmission-type liquid crystal display floater 610 of light conductor 20B that is possessed as the lighting device 620 of backlight, lighting device 620 becomes one with transmission-type liquid crystal display floater 610, therefore, realized the slimming of display unit.
If form the different different index layer of refractive index between the substrate 412 of transmission-type liquid crystal display floater 610 and the liquid crystal layer 413 with substrate 412, then inject the light of light conductor 20B inside in the surface reflections of substrate 412 with this different index layer from light source 10, transmit efficiently in light conductor 20B inside, therefore, the light from light source 10 can be used as illumination light effectively.
In addition, if between the substrate 412 of transmission-type liquid crystal display floater 610 and liquid crystal layer 413 polariscope is set, the polarisation of light direction of then injecting liquid crystal layer 413 can be further neat, therefore can improve display quality.
In addition, in the present embodiment, as the incorporate transmissive liquid crystal display device of the lighting device 620 of backlight and transmission-type liquid crystal display floater 610 600 as example; But the present invention is not limited to this, also is applicable to lighting device and the incorporate reflection-type liquid-crystal display device of reflective liquid crystal display floater as front light-source.
The invention provides and can use this lighting device penetrating the lighting device that go fully efficiently as the light of particular polarization from the light of light source, can provide light the utilization ratio height, can realize the image display device of the demonstration that becomes clear.
Lighting device of the present invention is particularly suitable for backlight or the front light-source as liquid crystal indicator.
Claims (34)
1. lighting device, it possesses: light source; And light conductor, have acceptance from the plane of incidence of the light of above-mentioned light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected,
Above-mentioned light conductor has: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization,
Above-mentioned polarised light selects layer in fact only the light of above-mentioned particular polarization to be reflexed to above-mentioned exit facet one side.
2. lighting device as claimed in claim 1, above-mentioned polarised light select layer to comprise a plurality of dielectric films that become predetermined angular with above-mentioned exit facet.
3. lighting device, it possesses: light source; And light conductor, have acceptance from the plane of incidence of the light of above-mentioned light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected,
Above-mentioned light conductor has: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization,
Above-mentioned polarised light selection layer comprises a plurality of dielectric films with respect to above-mentioned exit facet inclination, and a plurality of dielectric films above-mentioned plane of incidence of distance configuration far away more of above-mentioned inclination is intensive more.
4. lighting device as claimed in claim 3, the structure of above-mentioned light conductor comprises: the 1st parts, have a plurality of inclined planes of comprising to tilt with respect to above-mentioned exit facet and with the interarea of a plurality of parallel surfaces of above-mentioned exit facet almost parallel; And the 2nd parts, be arranged on the above-mentioned interarea of above-mentioned the 1st parts, make above-mentioned interarea planarization,
A plurality of dielectric films of above-mentioned inclination are formed on above-mentioned a plurality of inclined planes of above-mentioned interarea,
Above-mentioned a plurality of parallel surface above-mentioned plane of incidence of distance configuration far away more of above-mentioned interarea is sparse more.
5. lighting device as claimed in claim 4, above-mentioned polarised light select layer also to be included in a plurality of dielectric films that form on above-mentioned a plurality of parallel surfaces of above-mentioned interarea.
6. lighting device as claimed in claim 5, above-mentioned polarised light select layer to be configured near the above-mentioned exit facet, and, than more close above-mentioned exit facet one side of above-mentioned polarised light transform layer.
7. lighting device as claimed in claim 6, above-mentioned a plurality of parallel surfaces are than more close above-mentioned exit facet one side in above-mentioned a plurality of inclined planes.
8. lighting device as claimed in claim 5, above-mentioned light conductor also have the opposed faces relative with above-mentioned exit facet, and above-mentioned polarised light selects layer to be configured near the above-mentioned opposed faces, and, than more close above-mentioned opposed faces one side of above-mentioned polarised light transform layer.
9. lighting device as claimed in claim 8, above-mentioned a plurality of parallel surfaces are than more close above-mentioned opposed faces one side in above-mentioned a plurality of inclined planes.
10. as any one described lighting device of claim 4 to 9, above-mentioned the 1st parts are prismatic lenses of having arranged a plurality of prisms on above-mentioned interarea.
11. as any one described lighting device of claim 4 to 10, above-mentioned the 2nd parts are the transparent resin layers that formed by transparent resin material.
12. as any one described lighting device of claim 1 to 11, above-mentioned polarised light transform layer is formed by the transparent material with birefringence.
13. lighting device as claimed in claim 12, above-mentioned polarised light transform layer are the transparent resin layers of ejection formation.
14. lighting device as claimed in claim 12, above-mentioned polarised light transform layer is a retardation plate.
15. lighting device as claimed in claim 14, slow axes that above-mentioned retardation plate is had in being parallel to the face of above-mentioned exit facet and fast axis and above-mentioned particular polarization are inconsistent.
16. a lighting device, it possesses: light source; And light conductor, have acceptance from the plane of incidence of the light of above-mentioned light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected,
Above-mentioned light conductor has: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization,
Above-mentioned polarised light transform layer is ejection formation, the transparent resin layer with birefringence.
17. a lighting device, it possesses: light source; And light conductor, have acceptance from the plane of incidence of the light of above-mentioned light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected,
Above-mentioned light conductor has: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization,
Above-mentioned polarised light transform layer is a retardation plate,
Slow axes that above-mentioned retardation plate is had in being parallel to the face of above-mentioned exit facet and fast axis and above-mentioned particular polarization are inconsistent.
18. as claim 15 or 17 described lighting devices, above-mentioned retardation plate has the refractive index anisotropy of uniaxiality.
19. lighting device as claimed in claim 18 is along the axial refractive index n of the slower rays of above-mentioned retardation plate
x, along the refractive index n of the fast axis direction of above-mentioned retardation plate
y, above-mentioned retardation plate the refractive index n of thickness direction
z, above-mentioned retardation plate the slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate satisfy (n
x-n
z)/(n
x-n
y) 0 and 0＜(n
x-n
y) relation of d＜λ and 10 °＜α＜30 ° or 40 °＜α＜60 °.
20. lighting device as claimed in claim 18 is along the axial refractive index n of the slower rays of above-mentioned retardation plate
x, along the refractive index n of the fast axis direction of above-mentioned retardation plate
y, above-mentioned retardation plate the refractive index n of thickness direction
z, above-mentioned retardation plate the slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate satisfy (n
x-n
z)/(n
x-n
y) 0, (n
x-n
y) relation of d=λ/2 and 10 °＜α＜30 °.
21. lighting device as claimed in claim 18 is along the axial refractive index n of the slower rays of above-mentioned retardation plate
x, along the refractive index n of the fast axis direction of above-mentioned retardation plate
y, above-mentioned retardation plate the refractive index n of thickness direction
z, above-mentioned retardation plate the slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate satisfy (n
x-n
z)/(n
x-n
y) 1, λ/4＜(n
x-n
y) relation of d＜5 λ/4 and 20 °＜α＜90 °.
22. lighting device as claimed in claim 18 is along the axial refractive index n of the slower rays of above-mentioned retardation plate
x, along the refractive index n of the fast axis direction of above-mentioned retardation plate
y, above-mentioned retardation plate the refractive index n of thickness direction
z, above-mentioned retardation plate the slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate satisfy (n
x-n
z)/(n
x-n
y) 1, (n
x-n
y) relation of d=λ/2 and 20 °＜α＜80 °.
23. as claim 15 or 17 described lighting devices, above-mentioned retardation plate has the refractive index anisotropy of biaxiality.
24. lighting device as claimed in claim 23 is along the axial refractive index n of the slower rays of above-mentioned retardation plate
x, along the refractive index n of the fast axis direction of above-mentioned retardation plate
y, above-mentioned retardation plate the refractive index n of thickness direction
z, above-mentioned retardation plate the slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate satisfy 0.6＜(n
x-n
z)/(n
x-n
y)＜0.9, λ/4＜(n
x-n
y) relation of d＜3 λ/4 and 60 °＜α＜80 °.
25. lighting device as claimed in claim 23 is along the axial refractive index n of the slower rays of above-mentioned retardation plate
x, along the refractive index n of the fast axis direction of above-mentioned retardation plate
y, above-mentioned retardation plate the refractive index n of thickness direction
z, above-mentioned retardation plate the slow axes angulation α of thickness d, visible wavelength λ and above-mentioned particular polarization and above-mentioned retardation plate satisfy 0.6＜(n
x-n
z)/(n
x-n
y)＜0.9, (n
x-n
y) relation of d=λ/2 and 60 °＜α＜80 °.
26. as claim 1, any one described lighting device of 4 and 16, above-mentioned polarised light transform layer is configured in respect to above-mentioned polarised light and selects a layer side opposite with above-mentioned exit facet.
27. as claim 1, any one described lighting device of 4 and 17, above-mentioned polarised light transform layer is configured in above-mentioned exit facet one side of selecting layer with respect to above-mentioned polarised light.
28. an image display device, it has:
Any one described lighting device as claim 1 to 27; And
Be arranged on above-mentioned exit facet one side of the above-mentioned light conductor that above-mentioned lighting device has and possess at least 1 polariscopic display floater.
29. image display device as claimed in claim 28, above-mentioned lighting device also possess the transparent input unit that forms on the above-mentioned opposed faces of above-mentioned light conductor.
30. image display device as claimed in claim 29, above-mentioned display floater comprises substrate, the above-mentioned light conductor double as aforesaid substrate that above-mentioned lighting device had.
31. a light conductor has acceptance from the plane of incidence of the light of light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, wherein,
Also have: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization,
Above-mentioned polarised light selects layer in fact only the light of above-mentioned particular polarization to be reflexed to above-mentioned exit facet one side.
32. a light conductor has acceptance from the plane of incidence of the light of light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, wherein,
Also have: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization,
Above-mentioned polarised light selection layer comprises a plurality of dielectric films with respect to above-mentioned exit facet inclination, and a plurality of dielectric films above-mentioned plane of incidence of distance configuration far away more of above-mentioned inclination is intensive more.
33. a light conductor has acceptance from the plane of incidence of the light of light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, wherein,
Also have: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization,
Above-mentioned polarised light transform layer is ejection formation, the transparent resin layer with birefringence.
34. a light conductor has acceptance from the plane of incidence of the light of light source ejaculation and the exit facet that will penetrate from the light that the above-mentioned plane of incidence is injected, wherein,
Also have: polarised light is selected layer, will penetrate from above-mentioned exit facet selectively by the light of particular polarization from the light that the above-mentioned plane of incidence is injected; And the polarised light transform layer, the light of polarization direction that will be different with above-mentioned particular polarization is transformed to the light of above-mentioned particular polarization,
Above-mentioned polarised light transform layer is a retardation plate,
Slow axes that above-mentioned retardation plate is had in being parallel to the face of above-mentioned exit facet and fast axis and above-mentioned particular polarization are inconsistent.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP322454/2002 | 2002-11-06 | ||
| JP2002322454 | 2002-11-06 | ||
| JP161135/2003 | 2003-06-05 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1735768A true CN1735768A (en) | 2006-02-15 |
| CN100591989C CN100591989C (en) | 2010-02-24 |
Family
ID=36077558
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200380108404A Expired - Fee Related CN100591989C (en) | 2002-11-06 | 2003-10-28 | Lighting device and image display unit and light guide provided with it |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100591989C (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101842738B (en) * | 2007-10-30 | 2012-06-20 | 第一毛织株式会社 | Light guide panel for LCD back light unit and LCD back light unit thereby |
| CN104122707A (en) * | 2014-07-09 | 2014-10-29 | 京东方科技集团股份有限公司 | Lamp display device |
| CN104730768A (en) * | 2015-04-09 | 2015-06-24 | 京东方科技集团股份有限公司 | Reflection-type display device and display method thereof |
| CN105974514A (en) * | 2016-07-22 | 2016-09-28 | 京东方科技集团股份有限公司 | Light guide plate, backlight module and display device |
| CN107272250A (en) * | 2017-07-07 | 2017-10-20 | 上海天马微电子有限公司 | A kind of display panel and display device |
| WO2019019888A1 (en) * | 2017-07-28 | 2019-01-31 | Smart Liquid Crystal Technologies Co., Ltd. | A polarizing backlight unit, method of manufacturing the same and liquid crystal display device using the same |
-
2003
- 2003-10-28 CN CN200380108404A patent/CN100591989C/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101842738B (en) * | 2007-10-30 | 2012-06-20 | 第一毛织株式会社 | Light guide panel for LCD back light unit and LCD back light unit thereby |
| CN104122707A (en) * | 2014-07-09 | 2014-10-29 | 京东方科技集团股份有限公司 | Lamp display device |
| CN104122707B (en) * | 2014-07-09 | 2017-06-06 | 京东方科技集团股份有限公司 | A kind of light fixture display device |
| CN104730768A (en) * | 2015-04-09 | 2015-06-24 | 京东方科技集团股份有限公司 | Reflection-type display device and display method thereof |
| CN104730768B (en) * | 2015-04-09 | 2017-10-27 | 京东方科技集团股份有限公司 | Reflective display and its display methods |
| CN105974514A (en) * | 2016-07-22 | 2016-09-28 | 京东方科技集团股份有限公司 | Light guide plate, backlight module and display device |
| CN105974514B (en) * | 2016-07-22 | 2018-12-11 | 京东方科技集团股份有限公司 | Light guide plate, backlight module and display device |
| CN107272250A (en) * | 2017-07-07 | 2017-10-20 | 上海天马微电子有限公司 | A kind of display panel and display device |
| WO2019019888A1 (en) * | 2017-07-28 | 2019-01-31 | Smart Liquid Crystal Technologies Co., Ltd. | A polarizing backlight unit, method of manufacturing the same and liquid crystal display device using the same |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100591989C (en) | 2010-02-24 |
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