JP2013020932A - Optical module and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical module that can adjust illuminance distribution without using a light guide plate.SOLUTION: The optical module 20 includes a light-guiding optical sheet 30, a deflection optical sheet 50 arranged at a position facing to the light-guiding optical sheet, a reflecting sheet 21 that is arranged at a position facing to the light-guiding optical sheet from a reverse side to the deflection optical sheet, and a light source 25. The light-guiding optical sheet 30 has a first body part 31 and a plurality of first unit optical elements 35 which are aligned on the first body part and of which each one extends in one direction. The deflection optical sheet 50 has a second body part 55 and second unit optical elements 60 which are aligned on the second body part and project toward the side of the light-guiding optical sheet. The light source irradiates light going from one side to the other side in that one direction, on a region between the light-guiding optical sheet and the reflecting sheet.

Description

  The present invention relates to an optical module including a light source, a reflection sheet, a light guide optical sheet, and a deflection optical sheet, and a display device including the optical module.

  Today, an optical module having a light source, a reflective sheet, and a deflecting optical sheet is used in various optical devices. As a typical use example, the optical module is used in a display device, particularly a liquid crystal display device. As disclosed in, for example, Patent Document 1, the liquid crystal display device includes a liquid crystal display panel and a surface light source device that functions as a backlight that illuminates the liquid crystal display panel.

  As shown in FIG. 25, the conventional backlight includes light sources 25a and 25b including a light emitting unit 26, a reflection sheet D for directing light source light toward the liquid crystal display panel, and the liquid crystal display panel and the reflection sheet D. And a number of optical sheets disposed therebetween. Many optical sheets are designed so that the liquid crystal display panel can be illuminated with desired optical characteristics by changing the traveling direction of light from the light emitting section. The backlight shown in FIG. 25 is configured as an edge light type, and a light guide plate A, a deflection sheet B, and a light diffusion sheet C are provided in this order from the reflection sheet D side to the liquid crystal display panel side. . The light emitting units 26 of the light sources 25a and 25b are arranged on the side of the light guide plate A, and the light emitted from the light emitting unit 26 enters the light guide plate A from the side surface of the light guide plate A. The light that has entered the light guide plate is repeatedly reflected by the pair of main surfaces of the light guide plate A, and is guided toward the side surface opposite to the incident surface. The light traveling in the light guide plate is gradually emitted from one main surface (light exit surface) of the light guide plate as it proceeds in the light guide direction. As a result, the amount of light emitted from the light exit surface of the light guide plate is made uniform to some extent along the light guide direction. The light emitted from the light guide plate A enters the deflection sheet B, and then enters the light diffusion sheet C. The deflection sheet B has a function (deflection function) for narrowing the traveling direction of light to the front direction and improving the luminance in the front direction.

  On the other hand, as shown in FIG. 25, the liquid crystal display panel includes a liquid crystal cell 11 capable of controlling the orientation of liquid crystal for each pixel, a lower polarizing plate 13 disposed on the light incident side of the liquid crystal cell, and a liquid crystal cell. 11 and an upper polarizing plate 12 disposed on the light output side. The pair of polarizing plates 12 and 13 is a polarizer that transmits light of a specific polarization component and absorbs light of components other than the specific polarization component, a protective film that is bonded to the polarizer and protects the polarizer, have.

JP 2007-227405 A

  That is, in the edge-light type surface light source device shown in FIG. 25, the light source is arranged on the side of the optical sheet, and the light distribution is made uniform along the light guide direction by the light guide plate. Yes. As a result, in the edge light type surface light source device, since it is not necessary to arrange the light source at a position facing the optical sheet, the thickness of the surface light source device and the thickness of the display device incorporating the surface light source device can be reduced. It becomes possible.

  However, the thickness of the light guide plate that guides the light from the light source is thicker than the width of the light emitting portion of the light emitting portion of the light source in order to effectively use the light from the light source, and as a result, the thickness of the other optical sheets It becomes very thick compared to. For this reason, the material cost of a light-guide plate is high, and it will also obstruct the thickness reduction and weight reduction of a surface light source device and a display apparatus. Furthermore, it may be necessary to provide a special support structure for supporting the light guide plate.

  The present invention has been made in consideration of the above points, and provides an optical module capable of adjusting the illuminance distribution without using a thick light guide plate, and a display device including the optical module. With the goal.

The optical module according to the present invention comprises:
A light guide optical sheet having a sheet-like first main body portion and a plurality of first unit optical elements that are arranged on the first main body portion and each extend in one direction;
A deflection optical sheet disposed at a position facing the light guide optical sheet, and is arranged on the sheet-like second main body portion and the second main body portion and protrudes toward the light guide optical sheet side A deflecting optical sheet having a second unit optical element;
A reflection sheet disposed at a position facing the light guide optical sheet from the side opposite to the deflection optical sheet;
A light source that irradiates a region between the light guide optical sheet and the reflection sheet with light traveling from one side to the other side in the one direction.

  In the optical module according to the present invention, the first unit optical element of the light guide optical sheet may protrude from the first main body portion toward the deflecting optical sheet.

  The optical module by this invention WHEREIN: The said 1st unit optical element of the said light guide optical sheet may protrude toward the said reflective sheet side from the said 1st main-body part.

  In the optical module according to the present invention, the deflection optical sheet may be bonded to the light guide optical sheet.

  In the optical module according to the present invention, the deflecting optical sheet may be bonded to the light guide optical sheet via the top of the second unit optical element.

  In the optical module according to the present invention, the deflecting optical sheet is provided on the second main body part or via a spacer provided between the deflecting optical sheet and the light guiding optical sheet. The top of the second unit optical element of the deflecting optical sheet may be exposed separately from the light guide optical sheet.

  In the optical module according to the present invention, each second unit optical element may extend in the other direction intersecting the one direction on the second main body.

  In the optical module according to the present invention, the light source may include one or more light emitting units, and the light emitting units may be arranged so that an optical axis thereof is directed to a position on the light guide optical sheet.

  In the optical module according to the present invention, the light source may include one or more light emitting units, and the light emitting units may be arranged so that an optical axis thereof is directed to a position on the reflection sheet.

  In the optical module according to the present invention, the light guide optical sheet may be made of a thermoplastic resin.

  In the optical module according to the present invention, the thickness of the first main body portion along the normal direction to the sheet surface of the light guide optical sheet is the light source along the normal direction to the sheet surface of the light guide optical sheet. It may be thinner than the width of the light emitting part.

  The optical module according to the present invention may further include a second light source that irradiates a region between the light guide optical sheet and the reflective sheet with light traveling from one side to the other side in the one direction.

  The optical module according to the present invention may further include a polarizer provided on a side of the deflecting optical sheet opposite to the side facing the light guide optical sheet.

  In the optical module according to the present invention, the light guide optical sheet may contain a light diffusion component.

  In the optical module according to the present invention, the light guide optical sheet may have a light extraction element.

  In the optical module according to the present invention, the deflection optical sheet may include a light diffusion component.

  The optical module by this invention WHEREIN: The said light guide optical sheet may consist of the extrusion material produced by the extrusion process.

In the optical module according to the present invention,
The plurality of unit optical elements of the deflection optical sheet are arranged in the one direction, and each unit optical element extends linearly in a direction intersecting the one direction,
In the cross section orthogonal to the longitudinal direction of the unit optical element, the outer contour of the unit optical element has at least a top side and a base end of a section from the top most spaced from the main body to the base end connected to the main body. It has a shape along a parabola that is different in two sections on the part side, and in the cross section, defines an X axis parallel to the surface of the main body part facing the reflecting surface and a Z axis orthogonal to the X axis And, when the position of the top of the unit optical element is the origin of the X axis and the Z axis, and when the body portion side is the negative side of the Z axis as viewed from the origin
The parabola on the top side is represented by “Z = −aX ² ”,
The parabola on the base end side is represented by “Z = −bX ² + h”, and
The following expressions (1) and (2) may be satisfied.
0 <a <b Formula (1)
0 <h Formula (2)

  The display device according to the present invention includes any of the optical modules according to the present invention described above.

  In the display device according to the present invention, the deflection optical sheet may form a surface on the most incident side of the liquid crystal display panel.

  According to the present invention, the illuminance distribution can be adjusted without using a light guide plate.

FIG. 1 is a perspective view showing a schematic configuration of a display device and an optical module for explaining an embodiment according to the present invention. FIG. 2 is a side view showing the display device and the optical module. FIG. 3 is a plan view for explaining the positional relationship between the light guide optical sheet and the deflecting optical sheet and the light emitting part of the light source. FIG. 4 is a cross-sectional view showing the light guide optical sheet in a cross section taken along the line IV-IV in FIG. 2. FIG. 5 is a perspective view showing a deflection optical sheet. FIG. 6 is a view showing a polarizing plate in the same cross section as FIG. 2, and is a view for explaining a modification of the deflection optical sheet. FIG. 7 is a view showing the polarizing plate in the same cross section as FIG. 2, and is a view for explaining another modified example of the deflection optical sheet. FIG. 8 is a view showing the polarizing plate in the same cross section as FIG. 2, and is a view for explaining still another modified example of the deflection optical sheet. FIG. 9 is an enlarged view of the second unit optical element of the deflection optical sheet shown in FIG. 8 in the same cross section as FIG. FIG. 10 is a view showing the deflection optical sheet in the same cross section as FIG. 2, and is a view for explaining still another modification of the deflection optical sheet. FIG. 11 is a view showing the deflection optical sheet in the same cross section as FIG. 2, and is a view for explaining still another modification of the deflection optical sheet. FIG. 12 is a view showing the deflecting optical sheet in the same cross section as FIG. 2, and is a view for explaining still another modified example of the deflecting optical sheet. FIG. 13 is a view showing the deflection optical sheet in the same cross section as FIG. 2, and is a view for explaining still another modification of the deflection optical sheet. FIG. 14 is a perspective view showing a light diffusion layer of the deflection optical sheet, and is a view for explaining a modification of the light diffusion layer. FIG. 15 is a view corresponding to FIG. 1 and a perspective view for explaining a modification of the optical module. FIG. 16 is a cross-sectional view for explaining another modification of the optical module in the same cross section as FIG. FIG. 17 is a cross-sectional view for explaining still another modification example of the optical module in the same cross section as FIG. FIG. 18 is a cross-sectional view for explaining still another modification of the optical module in the same cross section as FIG. FIG. 19 is a cross-sectional view for explaining still another modification of the optical module in the same cross section as FIG. FIG. 20 is a cross-sectional view for explaining still another modification example of the optical module in the same cross section as FIG. FIG. 21 is a cross-sectional view for explaining still another modification example of the optical module in the same cross section as FIG. FIG. 22 is a diagram showing a modification of the liquid crystal display panel from the side. FIG. 23 is a diagram for explaining a modification of the light source. FIG. 24 is a graph showing a distribution along the first direction of the illuminance measured for each optical module. FIG. 25 is a cross-sectional view showing a display device including a conventional surface light source device. FIG. 26 is a diagram corresponding to FIG. 2 for explaining another modification of the light source. FIG. 27 is a diagram corresponding to FIG. 2 for explaining another modification of the light source. FIG. 28 is a diagram corresponding to FIG. 2, for explaining another modification example of the light source.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual ones.

  1 to 5 are diagrams for explaining an embodiment according to the present invention. Among these, FIG. 1 and FIG. 2 are a perspective view and a side view showing schematic configurations of the display device and the optical module, respectively. FIG. 3 is a plan view showing the optical module, and shows the positional relationship between the light guide optical sheet and the deflection optical sheet of the optical module and the light emitting part (light emitter) of the light source. FIG. 4 is a cross-sectional view of the light guide optical sheet, and FIG. 5 is a perspective view showing the deflection optical element.

  The display device 10 shown in FIG. 1 is a liquid crystal display device, and is disposed on the liquid crystal display panel 15 and on the back side of the liquid crystal display panel 15, in other words, on the side opposite to the viewer side with respect to the liquid crystal display panel. In the region between the light guide optical sheet 30, the reflection sheet (reflector, reflection element, reflection member) 21 disposed on the back side of the light guide optical sheet 30, and the light guide optical sheet 30 and the reflection sheet 21. And a light source 25 that emits light from the side. The liquid crystal display panel 15 is a device that forms an image by functioning as a shutter that controls transmission or blocking of light for each pixel of the color filter.

  As will be described in detail later, the liquid crystal display panel 15 includes a pair of polarizing plates 12 and 40 and a liquid crystal cell 11 disposed between the pair of polarizing plates. Then, the optical module 20 is formed by the deflection optical sheet 50, the light guide optical sheet 30, the light source 25, and the reflection sheet 21 of one polarizing plate 40 located on the most light incident side of the liquid crystal display panel 15. ing. In the following, in order to distinguish a pair of polarizing plates included in the liquid crystal display panel 15, the light incident side polarizing plate 40 is referred to as a lower polarizing plate regardless of the arrangement state of the display device 10, and the light emitting side polarized light. The plate 12 is called an upper polarizing plate.

  In addition, as shown in FIGS. 1-5, in this Embodiment, a pair of polarizing plates 12 and 40 and the liquid crystal cell 11 as a component which comprises the liquid crystal display panel 15, and the liquid crystal display panel 15, further, The deflecting optical sheet 50 that also functions as a protective film for the polarizer 41 in the lower polarizing plate 40 described later is configured to have a quadrangular shape in plan view. As a result, each member (each component) There are two pairs of edges, a pair of edges facing one direction d1 and a pair of other edges facing the second direction d2. Corresponding to the configuration of the liquid crystal display panel 15, the light guide optical sheet 30 disposed at a position facing the liquid crystal display panel 15 is also configured to have a quadrangular shape in plan view, and is arranged in the first direction d1. It has two pairs of edge parts of a pair of edge parts 30c1 and 30c2 which oppose, and another pair of edge parts which oppose the 2nd direction d2. In the present embodiment, the first direction d1 and the second direction d2 are orthogonal to each other.

  As will be described in detail later, the light emitted from the light emitting unit 26 of the light source 25 enters the light guide optical sheet 30 directly or after being reflected by the reflection sheet 21. As will be described later, the light guide optical sheet 30 exhibits a function of making the light amount distribution along the first direction uniform, and thereby the liquid crystal display panel 15 is evenly illuminated along the first direction. . Hereinafter, the light guide optical sheet 30, the reflection sheet 21, the light source 25, and the liquid crystal display panel 15 will be described in order.

  In the present specification, the “light exit side” refers to the downstream side of the optical path planned for the observer (the right side of the paper in FIGS. 1 and 2), that is, the observer side. The “light incident side” is the upstream side in the planned optical path. Further, the “back side” is the side opposite to the “light emission side” in the front direction.

  Further, in the present specification, the terms “sheet” and “film” are not distinguished from each other only based on the difference in names. Therefore, for example, “sheet” is a concept including a member that can also be called a film, and is not distinguished only by its name. As a specific example, the “light guide optical sheet” includes a member that can be called “light guide optical film”, and the “deflection optical sheet” also includes a member that can be called “deflection optical film”. Similarly, the “reflective sheet” includes a member that can be called a “reflective sheet”.

  Further, in this specification, the “front direction” means a light incident side surface (a surface facing the light guide optical sheet 30) 55 b of a second main body portion 55, which will be described later, of the deflection optical sheet 50 constituting the optical module 20. It points to the normal direction nd to. The front direction in the present embodiment is the normal direction to the display surface 10a of the display device 10 formed by the surface of the liquid crystal display panel 15 closest to the observer (most light-emitting side), and the liquid crystal display panel 15 The normal direction to the panel surface, the normal direction to the plate surface of the lower polarizing plate 40, the normal direction to the sheet surface of the deflection optical sheet 50, and the sheet surface of the second main body portion 55 described later of the deflection optical sheet 50 , The normal direction to the sheet surface of the light guide optical sheet 30, the normal direction to the sheet surface of the first main body 31 described later of the light guide optical sheet 30, and the like. Further, in this specification, the “panel surface (sheet surface, film surface, plate surface)” is the plane of the target sheet-like member when the target sheet-like member is viewed overall and globally. A surface that matches the direction.

  Furthermore, the terms used in this specification for specifying shapes and geometric conditions, for example, terms such as “parallel” and “orthogonal” are not limited to strict meaning, and expect similar optical functions. Interpretation will be made including possible errors.

  First, the light guide optical sheet 30 will be described. The light guide optical sheet 30 is disposed at a position facing the deflection optical sheet 50 of the lower polarizing plate 40 located on the most incident light side of the liquid crystal display panel 15 from the back side. The light guide optical sheet 30 has a function of guiding light emitted from the light source 25 in a direction away from the light source 25 in the first direction d1. For this reason, the distribution of the amount of light emitted from the light guide optical sheet 30 along the first direction d1 is made uniform.

  As shown well in FIG. 4, the light guide optical sheet 30 includes a sheet-like first main body portion 31, first unit optical elements 35 arranged side by side on the light exit side surface 31 a of the first main body portion 31, and have. Each first unit optical element 35 extends in a direction intersecting with the arrangement direction and parallel to the film surface of the light guide optical sheet 30. Further, the first unit optical elements 35 included in the light guide optical sheet 30 are configured identically. As shown in FIGS. 1-3, in this Embodiment, the 1st unit optical element 35 is extended linearly in parallel with the 1st direction d1. The first unit optical elements 35 are arranged without gaps in the second direction d2 on the first main body 31 and form the light exit side surface 30a of the light guide optical sheet 30.

  The “unit optical element” in the present specification refers to an element having a function of changing the traveling direction of the light by exerting an optical action such as refraction or reflection on the light. ”,“ Unit prism ”, and“ unit lens ”are not distinguished based only on the difference in designation and elements. Similarly, “prism” and “lens” are not distinguished from each other based solely on the difference in designation.

  By the way, the liquid crystal display panel 15 defines a large number of pixels. The liquid crystal display panel 15 forms an image by controlling transmission and blocking of light for each pixel. The arrangement direction of the first unit optical elements 35 intersects with the arrangement direction of the pixels of the liquid crystal cell 11 of the liquid crystal display panel 15 when viewed from the front direction nd, that is, is inclined or orthogonal to the arrangement direction of the pixels. It is preferable. Specifically, when viewed from the front direction, the arrangement direction of the first unit optical elements 35 and the arrangement direction of the pixels of the liquid crystal cell 11 are preferably inclined at an angle of 1 ° or more and less than 45 °. More preferably, it is inclined at an angle of 5 ° or more and 30 ° or less. In this case, moire (interference fringes) caused by interference between the periodicity due to the regular arrangement of the pixels and the periodicity due to the regular arrangement of the first unit optical elements 35 is effectively made inconspicuous. be able to. Further, from the viewpoint of making the moire inconspicuous, the arrangement pitch of the first unit optical elements 35 is preferably 30 μm or less. The above-described configuration for making the moire inconspicuous applies similarly to the first unit optical element 60 of the deflection optical sheet 50 described later.

  The cross section shown in FIG. 4 is a cross section along both directions of the arrangement direction of the first unit optical elements 35 and the normal direction to the first main body 31 formed of a sheet (hereinafter simply referred to as “light guide optical sheet”). This also corresponds to “main cut surface”. As shown in FIG. 4, each first unit optical element 35 has a triangular shape on the main cut surface. In particular, in the illustrated example, the cross-sectional shape of the main cutting surface of the first unit optical element 35 is an isosceles triangular shape that is arranged symmetrically about the normal direction to the sheet surface of the light guide optical sheet 30. ing. The angle θx (see FIG. 4) of the isosceles triangle shape can be set to, for example, 30 ° to 150 ° in consideration of the light guide function. Further, the width W1 (see FIG. 4) along the arrangement direction of the isosceles triangle can be, for example, 5 μm or more and 200 μm or less, and the height H1 along the front direction of the isosceles triangle (see FIG. 4). Can be, for example, 1 μm or more and 400 μm or less.

  As shown in FIGS. 2 and 4, the light guide optical sheet 30 includes a diffusing component 34. The diffusing component 34 causes the deflecting optical sheet 50 to exhibit a light diffusing function, thereby The direction of travel is changed. More precisely, the deflection optical sheet 50 includes a light diffusion layer 32 a having a main part 33 made of resin and a diffusion component 34 dispersed in the main part 33. In the light guide optical sheet 30 in the present embodiment, as well shown in FIGS. 2 and 4, the main body 31 is configured as a light diffusion layer 32a. On the other hand, the first unit optical element 35 forms a resin layer 32b that is located on the light diffusion layer 32a and does not contain the diffusion component 34.

  In the illustrated embodiment, the first unit optical element 35 protrudes from the first main body 31 toward the light output side, that is, toward the liquid crystal display panel 15 side. Accordingly, the first unit optical element 35 forms the light exit side surface 30 a of the light guide optical sheet 30, and the light entrance side surface 31 b of the first main body 31 forms the light entrance side surface 30 b of the light guide optical sheet 30. .

  Such a light guide optical sheet 30 is manufactured by, for example, extruding two layers of the light diffusion layer 32a and the resin layer 32b by coextrusion molding, and further shaping the first unit optical element 35 at the time of molding. Can be done. In the light guide optical sheet 30 manufactured by such a manufacturing method, there is no optical interface between the main portion 33 of the light diffusion layer 32a and the resin layer 32b.

  In addition, it is also possible to produce the light guide optical sheet 30 using an ionizing radiation curable resin. However, the light guide optical sheet 30 has a light guide function in the first direction d1, and light guided in the light guide optical sheet 30 is guided over a relatively long distance. Go through 30. For this reason, when the light guide optical sheet 30 is made using an ionizing radiation curable resin, light in a specific wavelength region of light from the light source is selectively absorbed by the light guide optical sheet, and the optical The color of the light emitted from the module 20 will change. On the other hand, according to the light guide optical sheet 30 produced by extruding a thermoplastic resin, for example, the light guide optical sheet 30 produced using polycarbonate as a main component (a component occupying more than half the weight%). According to this, it is possible to effectively suppress problems such as changes in color.

  As the resin material forming the resin layer 32b and the resin material forming the main portion 33 of the light diffusion layer 32a, various resin materials having excellent optical characteristics, for example, polycarbonate resins can be used.

  On the other hand, the diffusing component 34 dispersed in the light diffusing layer 32a may be composed of a granular material having a refractive index different from that of the main portion 33, or a granular material that itself has a reflectivity. The particulate matter forming the diffusing component 34 may be a metal compound, a porous material containing a gas, or a simple bubble. Further, the shape of the diffusion component 34 made of a granular material is not particularly limited. Therefore, the diffusion component 34 does not need to be spherical (particulate) as in the illustrated example, and can have various shapes such as a spheroid shape and a linear shape.

  Next, the reflection sheet 21 will be described. The reflection sheet 21 is disposed at a position facing the light guide optical sheet 30 from the front direction. The reflection sheet 21 has a reflection surface 22 that reflects light as a surface facing the light guide optical sheet 30. The reflection sheet 21 reflects light incident on the reflection surface 22 toward the light incident side surface 30 b of the light guide optical sheet 30.

  The reflection sheet 21 includes at least a reflection surface 22 made of a material having a high reflectance such as metal. The reflection sheet 21 in the present embodiment has a function of regularly reflecting incident light, for example, as shown in FIG. However, the reflection on the reflection sheet 21 is not limited to regular reflection, but may be diffuse reflection (irregular reflection, scattering reflection). When the reflection on the reflection sheet 21 is diffuse reflection, the reflection may be isotropic diffusion or anisotropic diffusion. For example, by forming irregularities on the reflection surface 22 of the reflection sheet 21 by embossing or the like, reflection on the reflection sheet 21 can be made isotropic diffusion. Further, for example, by applying a hairline process to the reflection surface 22 of the reflection sheet 21, the reflection on the reflection sheet 21 can be anisotropic diffusion. Furthermore, a transparent optical element such as a prism, a lens, and a microlens is provided on the flat reflecting surface 22 of the reflecting sheet 21. Due to these optical elements, the reflecting sheet 21 has an isotropic diffuse reflection function. Or you may make it express an anisotropic diffuse reflection function.

  As shown in FIGS. 1 and 2, the reflection sheet 21 is disposed at a position shifted from the light guide optical sheet 30 in the front direction. More specifically, the reflection sheet 21 is disposed at a position shifted from the light incident side surface 30 b of the light guide optical sheet 30 toward the back side along the front direction. Thereby, the light reflected by the reflection surface 22 of the reflection sheet 21 is directly incident on the light incident side surface 30b of the light guide optical sheet 30, in other words, is incident as it is without passing through another member. It is possible. In particular, in the present embodiment, as shown in FIG. 2, the reflection sheet 21 is disposed so that at least a part thereof faces the light guide optical sheet 30 in the front direction nd. That is, no other member is interposed between at least a part of the reflection sheet 21 and the light guide optical sheet 30, and the light reflected by at least a part of the reflection sheet 21 is directly transmitted to the light guide optical sheet. 30 can be incident.

  Next, the light source will be described. As shown in FIGS. 1 to 3, the light source 25 is provided in the vicinity of the edge portion 30 c 1 corresponding to one edge portion 30 c 1 of the light guide optical sheet 30 having a rectangular planar shape. And as shown in FIG. 3, the light emission part 26 radiates | emits light so that this edge part 30c1 may be crossed in planar view.

  As the light emitting unit 26 forming the light source 25, various known light emitting units, for example, a cold cathode tube, in particular, a cold cathode tube with a narrow light distribution direction can be used. However, in the illustrated example, the light source 25 is configured by a plurality of dot-like light emitting units 26, typically a plurality of light emitting diodes (LEDs) 26. A large number of point light-emitting portions 26 constituting the light source 25 are arranged side by side along the longitudinal direction of the edge portion 30 c 1 of the corresponding light guide optical sheet 30. In other words, in the present embodiment, a large number of point light emitting units 26 that form the light source 25 are arranged side by side in a second direction d2 orthogonal to the first direction d1.

As well shown in FIGS. 3 and 2, in the display device 10, the light emitting unit 26 that forms the light source 25 follows the outer contour of the liquid crystal display panel 15, as in the edge light type liquid crystal display device. It is located outside the outer contour. More specifically, the light emitting unit 26 of the light source 25 is disposed at a position that is outside the edge of the light guide optical sheet 30 in the observation from the front direction.
That is, as shown in FIG. 3, in the observation from the front direction, the light emitting unit 26 that constitutes the light source 25 has the liquid crystal display panel 15 (more precisely, the display surface 10 a that forms an image in the liquid crystal display panel 15. It is arranged at a position that does not overlap with the area to be made. As shown in FIG. 3, the outer contour of the light guide optical sheet 30 matches the outer contour of the liquid crystal display panel 15 in the observation from the front direction.

  Further, in the display device 10 according to the present embodiment, as shown in FIG. 2, the light emitting unit 26 that constitutes the light source 25 is arranged at a position shifted in the front direction from the liquid crystal display panel 15 and the light guide optical sheet 30. Yes. More specifically, the light emitting unit 26 that constitutes the light source 25 is a position that is shifted to the back side along the front direction from the back side surface (light incident side surface 30 b) of the light guide optical sheet 30. It is arrange | positioned in the position which shifted | deviated to the observer side along the front direction rather than the reflective surface 22 of this. With such an arrangement, the light source 25 irradiates the region between the reflective sheet 21 and the light guide optical sheet 30, and the light is on the side of the edge 30 c 1 of the light guide optical sheet 30 in the first direction. To the other edge 30c2. Therefore, the reflection surface 22 of the reflection sheet 21 and the light incident side surface 30b of the light guide optical sheet 30 can receive light emitted from the light source 25 directly, that is, without passing through another member.

  Further, unlike the conventional light guide plate A shown in FIG. 25, the light guide optical sheet 30 having a light guide function receives light source light not from the side end face but from the back side face. The thickness of the sheet 30 can be reduced regardless of the form of the light emitting portion 26 of the light source 25. In the conventional light guide plate A shown in FIG. 25, the thickness of the light guide plate along the normal direction of the light guide plate is determined from the viewpoint of causing light source light to enter the light guide plate with high efficiency. It was necessary to make it larger than the thickness of the light emitting part of the light source along the line. Specifically, since the thickness of the light emitting portion made of LEDs is 2 to 3 mm, the thickness of the conventional light guide plate A is usually 2 mm to 5 mm. On the other hand, as well shown in FIG. 2, in the present embodiment, the thickness tm of the first main body portion 31 along the normal direction to the light guide optical sheet 30 is set to 10 μm to 300 μmm. It can be made thinner than the thickness te of the light emitting portion 26 along the normal direction to the optical optical sheet 30. Furthermore, the thickness ts of the light guide optical sheet 30 along the normal direction to the light guide optical sheet 30 is set to 11 μm to 700 μm, and the thickness te of the light emitting unit 26 along the normal direction to the light guide optical sheet 30 is set. It is also possible to make it thinner. That is, the thickness ts and the first main body tm of the light guide optical sheet 30 can be reduced without considering the thickness of the light emitting unit 26 of the light source 25.

  By the way, the point light emission part 26 like LED does not light-emit radially with uniform luminous intensity, but has directivity. That is, the point light emission part 26 like LED radiates | emits light with a different luminous intensity (unit: candela) in each direction. In general, the light emitting unit 26 has a peak luminous intensity in a specific direction pd. As the inclination angle with respect to the specific direction pd increases, the value of the luminous intensity gradually decreases. Preferably, the arrangement of the light emitting units 26 constituting the light source 25 is determined in consideration of such directivity characteristics (light distribution characteristics, in other words, luminous intensity angle (direction) distribution). In the present specification, the above-described specific direction that provides the peak luminous intensity is referred to as an “optical axis”.

  As shown in FIG. 2, in a cross section parallel to both the front direction nd and the first direction d1, the optical axis pd of the light emitting unit 26 is inclined from the direction parallel to the sheet surface of the light guide optical sheet 30, and the reflection sheet From the 21 side toward the light guide optical sheet 30 side, that is, from the back side toward the observer side in the front direction. Further, the light emitting unit 26 is disposed so that the optical axis pd thereof faces the position on the light incident side surface 30 b of the light guide optical sheet 30.

  According to such an arrangement, most of the light emitted from the light emitting unit 26 of the light source 25 enters the light guide optical sheet 30. Moreover, most of the light from the light emitting section 26 travels substantially along the first direction d1 and prevents leakage from between the light guide optical sheet 30 and the reflection sheet 21 on the other side in the first direction d1. can do. Therefore, the loss of the light emitted by the light emitting unit 26 can be effectively prevented, and the energy efficiency of the optical module 20 and the display device 10 can be effectively improved.

  Note that, for example, when the light emitting unit 26 has no directivity or only weak directivity, all light emitted by the light emitting unit 26 does not go to the light guide optical sheet 30, but for example, as shown in FIG. As described above, part of the light emitted from the light emitting unit 26 (see the optical path L <b> 2 c) may enter the reflection sheet 21. Further, not all the light directed to the light guide optical sheet 30 is incident on the light guide optical sheet 30, and a part of the light is expected to be reflected by the light incident side surface 30 b of the light guide optical sheet 30. . Therefore, separately from the reflection sheet 21 disposed at the position facing the light guide optical sheet 30, or as an extension of the reflection sheet 21, the auxiliary reflection sheet 23 is shown as shown by a two-dot chain line in FIG. You may make it block | close between the reflective sheet 21 and the light guide optical sheet 50, and also between the reflective sheet 21 and the liquid crystal display panel 15 so that the light emission part 26 may be enclosed. According to the auxiliary reflection sheet 23, the light that could not enter the light guide optical sheet 30 can be directed again to the light guide optical sheet 30, and the light use efficiency from the light source 25 is effectively improved. be able to.

  Next, the liquid crystal display panel 15 will be described. As described above, the liquid crystal display panel 15 includes the pair of polarizing plates 12 and 40 and the liquid crystal cell 11 disposed between the pair of polarizing plates 12 and 40. Among these, the polarizing plates 12 and 40 have a function (absorption type polarization separation function) of decomposing incident light into orthogonal polarization components, transmitting one polarization component, and absorbing the other polarization component. Yes.

  The polarizing plates 12 and 40 have a function (absorptive polarization separation function) of decomposing incident light into orthogonal polarization components, transmitting one polarization component, and absorbing the other polarization component. On the other hand, the liquid crystal cell 11 has a pair of transparent substrates and a liquid crystal layer provided between the transparent substrates. An electric field can be applied to the liquid crystal layer for each region where one pixel is formed, and the alignment of the liquid crystal layer to which the electric field is applied changes. For example, the polarization component in a specific direction (direction parallel to the transmission axis) transmitted through the lower polarizing plate 40 disposed on the light incident side passes through a region of the liquid crystal layer to which an electric field is applied in the liquid crystal cell 11. At that time, the polarization direction is rotated by 90 °, and the polarization direction is maintained when passing through the liquid crystal layer to which no electric field is applied. For this reason, depending on whether or not an electric field is applied to each region of the liquid crystal layer, whether the polarization component in a specific direction transmitted through the lower polarizing plate 40 is further transmitted through the upper polarizing plate 12 disposed on the light output side of the lower polarizing plate 40. Alternatively, it is possible to control whether the light is absorbed and blocked by the upper polarizing plate 12.

  Here, the lower polarizing plate 40 will be described in further detail. The lower polarizing plate 40 includes a polarizer 41 that can exhibit an absorption polarization separation function, and a deflecting optical sheet 50 bonded to the polarizer 41. As shown in FIG. 2, the deflection optical sheet 50 is laminated on the polarizer 41 from the side not facing the liquid crystal cell 11, in other words, from the light incident side, and functions as a protective film that protects the polarizer 41 from the outside. It is like that.

  Further, an adhesive layer (not shown) is provided between the polarizer 41 and the deflection optical sheet 50 so as to be adjacent to the polarizer 41 and the deflection optical sheet 50 and adheres the polarizer 41 and the deflection optical sheet 50 to each other. May be provided. The adhesive layer for improving the adhesion between the polarizer 41 and the deflecting optical sheet 50 can be formed using various conventional adhesives. As one specific example, for example, an adhesive layer can be formed using an aqueous adhesive mainly composed of a polyvinyl alcohol-based resin. In addition, the adhesion in this specification is a concept including adhesion and gluing, and similarly, the adhesive in this specification is a concept including pressure-sensitive adhesive and glue.

  Various polarizers have been developed to date, and any of these polarizers can be used as the polarizer 41. As a specific example, a polarizer 41 having a polyvinyl alcohol film as a base material can be used. The polarizer 41 based on a polyvinyl alcohol film is anisotropic in absorbing light by adsorbing or dyeing a dichroic dye such as iodine or dye on the polyvinyl alcohol film, and then orienting it by uniaxial stretching. Can be imparted to the polyvinyl alcohol film.

  Next, the deflection optical sheet 50 will be described. The deflection optical sheet 50 described here has a light control function for changing the traveling direction of light. As a specific configuration, the light incident side surface 50b of the deflecting optical sheet 50 is an optical element formed by second unit optical elements (unit prisms) 60 arranged side by side as well shown in FIGS. It is configured as an element surface (prism surface). By this optical element surface, the deflecting optical sheet 50 exhibits a condensing function (deflecting function). The deflection optical sheet 50 includes a diffusion component 59b dispersed in a binder resin, and the deflection optical sheet 50 exhibits a light diffusion function by the diffusion component 59b. As described above, the deflection optical sheet 50 is positioned on the most light incident side of the liquid crystal display panel 15, and the light incident side surface 50 b of the deflection optical sheet 50 forms the light incident side surface of the liquid crystal display panel 15. Yes. Hereinafter, the configuration of the deflection optical sheet 50 will be further described in detail.

  As shown well in FIG. 5, the deflection optical sheet 50 includes a sheet-like second main body portion 55, a second unit optical element 60 arranged side by side on the light incident side surface 55 b of the second main body portion 55, and have. Each second unit optical element 60 extends in a direction intersecting with the arrangement direction and parallel to the sheet surface of the deflecting optical sheet 50. Further, the second unit optical elements 60 included in the deflecting optical sheet 50 are configured identically. As shown in FIGS. 1 to 3, in the present embodiment, the arrangement direction of the second unit optical elements 60 is parallel to the first direction d1, and each second unit optical element 60 is in the second direction d2. It extends along the straight line.

  The cross section shown in FIG. 2 is a cross section along the both directions of the arrangement direction of the second unit optical elements 60 and the normal direction to the second main body portion 55 made of a sheet (hereinafter simply referred to as “the main part of the deflection optical sheet”). This also corresponds to “cut plane”. As shown in FIG. 2, each second unit optical element 60 has a triangular shape on the main cut surface. In particular, in the illustrated example, the cross-sectional shape of the main cutting surface of the second unit optical element 60 is an isosceles triangle that is arranged symmetrically about the normal direction to the film surface of the deflecting optical sheet 50. Yes. The angle θy (see FIG. 2) of the isosceles triangle shape can be set to, for example, 15 ° to 100 ° in consideration of the light collecting function. Further, the width W2 (see FIG. 2) along the arrangement direction of the isosceles triangle can be, for example, 5 μm or more and 250 μm or less, and the height H2 along the front direction of the isosceles triangle (see FIG. 2). Can be, for example, 2.5 μm or more and 250 μm or less.

  Further, as described above, the deflection optical sheet 50 has the diffusion component 59b, and the deflection optical sheet 50 exhibits the light diffusion function by the diffusion component 59b. More precisely, the deflection optical sheet 50 includes a light diffusion layer 51a having a main part 59a made of resin and a diffusion component 59b dispersed in the main part 59a.

  The deflection optical sheet 50 in the present embodiment includes a light diffusion layer 51a and a resin layer 51b that does not contain the diffusion component 59b, as well shown in FIG. In the illustrated example, the resin layer 51b is disposed on the light incident side with respect to the light diffusion layer 51a. That is, the light diffusion layer 51a is disposed closer to the polarizer 41 than the resin layer 51b. The resin layer 51 b constitutes the above-described second unit optical element 60 and the light incident side portion of the second main body portion 55. On the other hand, the light diffusion layer 51a constitutes a light-emitting side portion of the second main body portion 55 adjacent to the resin layer 51b.

  Such a deflecting optical sheet 50 is manufactured by, for example, extruding two layers of the light diffusion layer 51a and the resin layer 51b by coextrusion molding, and further shaping the second unit optical element 60 at the time of molding. obtain. In the deflection optical sheet 50 manufactured by such a manufacturing method, there is no optical interface between the main portion 59a of the light diffusion layer 51a and the resin layer 51b. That is, the light enters the deflecting optical sheet 50 from the resin layer 51b to the light diffusion layer 51a without being optically affected.

  As the resin material forming the resin layer 51b and the resin material forming the main portion 59a of the light diffusion layer 51a, various resin materials having excellent optical characteristics, for example, polycarbonate resins can be used. The diffusion component 59b dispersed in the light diffusion layer 51a can be the same as the above-described diffusion component that can be used in the light guide optical sheet 30.

  The deflecting optical sheet 50 can exhibit a diffusing function for diffusing light due to the light diffusing layer 51a including the diffusing component 59b. The degree of the light diffusing function of the deflecting optical sheet 50 caused by the internally added diffusion component 59b is as follows. The resin material constituting the main portion 59a, the thickness of the main portion 59a, the configuration (shape, size ( By appropriately setting the particle size), the refractive index, etc.), the concentration of the diffusing component 59b, etc., it can be adjusted within a very wide range. Specifically, the haze value of the light diffusing layer 51a is set within a range that is not normally reached by simply matting (roughening) the surface layer, for example, within a range of 60% to 90%. It is also possible to set.

  Incidentally, the light incident side surface of the lower polarizing plate 40 and the light incident side surface 50 b of the deflection optical sheet 50 that forms the light incident side surface of the liquid crystal display panel 15 are formed as optical element surfaces composed of the second unit optical elements 60. . On the other hand, the light exit side surface 50a of the deflection optical sheet 50 is formed as a flat surface. Accordingly, it is possible to stably laminate and bond the deflecting optical sheet 50 and the polarizer 41 while preventing air and the like from being mixed.

  In this specification, “flat” used for the surface 50a of the deflecting optical sheet 50 facing the polarizer 41 ensures stable lamination and adhesion between the deflecting optical sheet 50 and the polarizer 41. It refers to the flatness you get. For example, when the surface roughness of the surface 50a facing the polarizer 41 of the deflecting optical sheet 50 is measured as a ten-point average roughness Rz in accordance with JIS B0601 (1982), it is 1.0 μm or less. If there is, it can be said that it is flat.

  In this way, the light exit side surface 50a of the deflecting optical sheet 50 is flat, although the deflecting optical sheet 50 has the diffusion component 59b internally added. The child 41 can be laminated and bonded. Specifically, the deflection optical sheet 50 and the polarizer 41 are overlapped with each other with an aqueous solution (or suspension) mixed with water or a suitable additive such as a surfactant interposed therebetween. I will match. Accordingly, the deflecting optical sheet 50 and the polarizer 41 can be stacked while preventing entry of foreign matters such as air. At this time, an adhesive (for example, glue) is mixed with water or an aqueous solution (or suspension), or an adhesive layer is provided in advance on at least one of the deflecting optical sheet 50 and the polarizer 41. The deflecting optical sheet 50 and the polarizer 41 may be positively bonded.

In addition, in order to promote the removal of moisture from the deflecting optical sheet 50 and the polarizer 41 after “water sticking”, the moisture permeability of the deflecting optical sheet 50 is 10 g under the condition of a temperature of 40 ° C. and a humidity of 90% RH. / m ² · 24 hr or more is preferable. However, if the moisture permeability is too high, warping or bending due to moisture absorption may occur. Therefore, the moisture permeability is preferably 400 g / m ² · 24 hr or less as measured at a temperature of 40 ° C. and a humidity of 90% RH. . In addition, the moisture permeability in this specification refers to the numerical value measured using the cup method based on JISZ0208.

  Next, operations of the display device 10 and the optical module 20 will be described mainly with reference to FIG.

  As described above, in the cross section shown in FIG. 2, the optical axis pd of the light emitting unit 26 is inclined from the direction parallel to the sheet surface of the light guide optical sheet 30 and directed toward the light guide optical sheet 30. Yes. In particular, in the present embodiment, the optical axis pd of the light emitting unit 26 is directed to the position on the light incident side surface 30b of the light guide optical sheet 30, and therefore the light emitting unit 26 of the light source 25 is the light guide optical sheet. Light is emitted toward the light incident side surface 30b. That is, most of the lights L2a and L2b emitted from the light emitting unit 26 of the light source 25 enter the light guide optical sheet 30 directly, that is, without entering other members. On the other hand, a part of the light L <b> 2 c emitted from the light emitting unit 26 of the light source 25 enters the reflection sheet 21 and is reflected by the reflection sheet 21 and then travels toward the light guide optical sheet 30.

  A lot of light L <b> 2 a incident on the light guide optical sheet 30 is totally reflected by the light exit side surface 30 a formed by the first unit optical element 35. If the light exit side surface 30a of the light guide optical sheet 30 is parallel to the incident side surface 30b, the light that has entered the light guide optical sheet 30 through the light incident side surface 30b has a traveling direction due to the diffusion component 34 and the like. Unless changed, the light does not enter the light emitting side surface 30a at an incident angle equal to or greater than the total reflection critical angle, and therefore does not totally reflect on the light emitting side surface 30a. On the other hand, the light exit side surface 30 a of the light guide optical sheet 30 described here is formed by the first unit optical element 35 protruding from the first main body portion 31 to the viewer side. That is, the light exit side surface 30a of the light guide optical sheet 30 is inclined with respect to the light entrance side surface 30b, and the incident angle when entering the light exit side surface 30a is a surface parallel to the light entrance side surface 30b. There is a tendency that the incident angle becomes larger than the incident angle when the light enters. This tendency becomes stronger with respect to light having a small angle formed by the traveling direction with respect to the first direction d1 in the observation from the front direction, and when the inclination angle of the light exiting side surface 30a with respect to the light incident side surface 30b is increased. Become stronger. From such a tendency, the typical light L2a that has entered the light guide optical sheet 30 enters the light exit side surface 30a at an incident angle that is equal to or greater than the total reflection critical angle, and is totally reflected by the light exit side surface 30a.

  When the light L2a incident on the light guide optical sheet 30 is totally reflected by the light exit side surface 30a of the light guide optical sheet 30, the traveling direction along the front direction is folded. The light L2a is then reflected by the incident surface 30b of the light guide optical sheet 30, or once emitted from the light guide optical sheet 30 and reflected by the reflection surface 22 of the reflection sheet 21, and again the light guide optical. Heading to the light exit side 30a of the sheet 30. During this time, the light continues to travel along the first direction d1. That is, the light guide optical sheet 30 guides light in the first direction d1 by reflection at the light exit side surface 30a. By such a light guide function of the light guide optical sheet 30, light can be guided to a region away from the light emitting unit 26 that tends to reduce the amount of light, that is, a region on the other side in the first direction d1. .

  On the other hand, the diffusion component 34 is dispersed in the light guide optical sheet 30. Therefore, as shown in FIG. 2, the light L2a and L2b guided in the first direction d1 in the light guide optical sheet 30 is irregularly changed in traveling direction by the diffusion component 34, and is less than the total reflection critical angle. May be incident on the light exit side surface 30a. In this case, the lights L2a and L2b can be emitted from the light guide optical sheet 30 via the light exit side surface 30a. The collision between the light traveling in the light guide optical sheet 30 and the diffusion component 34 dispersed in the light guide optical sheet 30 occurs in each section along the first direction d1 in the light guide optical sheet 30. . Thereby, the light traveling in the light guide optical sheet 30 in the direction away from the light emitting unit 26 along the first direction d1 is gradually emitted from the light exit side surface 30a toward the liquid crystal display panel 15. That is, the diffusion component 34 dispersed in the light guide optical sheet 30 functions as a light extraction element for extracting light traveling in the light guide optical sheet 30 from the light guide optical sheet 30.

  The degree of the light extraction function of the light guide optical sheet 30 due to the presence of the diffusion component 34 is the resin material forming the main part 33 of the light guide optical sheet 30, the thickness of the main part 33, and the diffusion component 34 of the light guide optical sheet 30. By appropriately setting the configuration (shape, size (particle size), refractive index, etc.), the concentration of the diffusion component 34, etc., it is possible to adjust within a very wide range.

  The light guide function and the light extraction function of the light guide optical sheet 30 described above can increase the density of light incident on the liquid crystal display panel 15 in a region away from the light emitting unit 26 that tends to reduce the amount of light. . Thereby, the distribution of the amount of light incident on each position along the first direction d1 of the liquid crystal display panel 15 can be made uniform. With regard to this point, the inventors of the present invention have made extensive studies. According to the configuration of the present embodiment, the first amount of incident light on the liquid crystal display panel 15 (deflection optical sheet 50) can be obtained without using a light guide plate. The distribution along the direction d1 can be adjusted as appropriate, and further, the liquid crystal display panel 15 (deflection optical sheet 50) can be adjusted to the extent required in practical display device applications, particularly large television receiver applications. The distribution along the first direction d1 of the amount of incident light on () was sufficiently uniformed.

  The first unit optical element 35 having a triangular cross-section protruding to the light exit side exhibits a light collecting function with respect to light of the component along the second direction d2 that is the arrangement direction. That is, the component of the light emitted from the first unit optical element 35 of the light guide optical sheet 30 along the second direction mainly has a small angle with respect to the front direction due to refraction at the first unit optical element 35. The traveling direction can be bent as follows. According to such a condensing function of the first unit optical element 35, the luminance in the front direction can be increased.

  The lights L2a and L2b emitted from the light guide optical sheet 30 travel to the liquid crystal display panel 15. On the most incident light side of the liquid crystal display panel 15, a lower polarizing plate 40 having a deflection optical sheet 50 and a polarizer 41 is provided. The deflecting optical sheet 50 of the lower polarizing plate 40 forms the most incident side surface of the liquid crystal display panel 15.

  As described above, the deflecting optical sheet 50 has a light collecting function (deflecting function) that changes the traveling direction of the light so that the angle formed by the traveling direction of the light with respect to the front direction nd is reduced as a whole. Has a light diffusion function of diffusing light. Among these, the light condensing function is expressed by the second unit optical element 60 of the deflecting optical sheet 50, and the light diffusing function is mainly expressed by the light diffusing layer 51 a of the deflecting optical sheet 50. The second unit optical element 60 forms the light incident side surface of the deflecting optical sheet 50, and the light diffusion layer 51 a is provided on the light exit side of the deflecting optical sheet 50. For this reason, the light incident on the deflecting optical sheet 50 is first given a condensing function and then given a light diffusing function.

  As is well shown in FIG. 2, the basic principle of the light collecting function by the second unit optical element 60 having a triangular cross section is that light incident from one surface (incident surface) 60b1 of the second unit optical element 60. L2a and L2b are totally reflected on the other surface (total reflection surface) 60b2, thereby reducing the angle at which the traveling direction of the light is formed with respect to the front direction nd. That is, the light collecting function by the second unit optical element 60 is mainly exerted on the light component parallel to the arrangement direction of the second unit optical elements 60. Then, by appropriately designing the cross-sectional shape of the second unit optical element 60, as shown in FIG. 2, the light condensing function in the second unit optical element 60 of the deflection optical sheet 50 is effectively exhibited. It becomes like this. Specifically, by appropriately setting the shape of the second unit optical element 60, the refractive index of the second unit optical element 60, etc., the degree of the light collecting function in the deflecting optical sheet 50 can be adjusted within a very wide range. It is.

  Further, the light condensing function by the second unit optical element 60 is exerted on the component in the direction orthogonal to the component exerting the light condensing function from the first unit optical element 35 of the light guide optical sheet 30. Therefore, the second unit optical element 60 does not significantly change the traveling direction of the component light condensed by the first unit optical element 35 of the light guide optical sheet 30, and the first unit optical element 35 and the second unit The optical element 60 can effectively improve the brightness in the front direction.

  Thus, the second unit optical element 60 of the deflecting optical sheet 50 is useful for improving the luminance in the front direction. In particular, in the present embodiment, since the diffusing component 59b is not dispersed in the second unit optical element 60, the surface (prism surface) of the second unit optical element 60 functioning as the incident surface 60b1 and the total reflection surface 60b2. In addition, it can be formed with high accuracy as a flat surface without unevenness due to the diffusion component 59b. Thereby, the 2nd unit optical element 60 of the deflection | deviation optical sheet 50 can exhibit the desired desired optical function.

  The light incident on the deflecting optical sheet 50 via the second unit optical element 60 then travels in the second main body 55 from the resin layer 51b to the light diffusion layer 51a having a light diffusion function. The light diffusion layer 51a has a main portion 59a and a diffusion component 59b dispersed in the main portion 59a, and expresses a light diffusion function due to the internally added diffusion component 59b. The light diffusing function in the light diffusing layer 51a due to the internally added diffusing component 59b is, for example, matting the surface by molding or providing a granular material on the surface layer to make the surface matte. Compared with the light diffusing function resulting from this, the degree (diffusion intensity) and quality (diffusion uniformity) are remarkably superior.

  Specifically, when the surface is merely matted, light that passes through (the traveling direction cannot be changed) inevitably occurs. On the other hand, according to the internally added diffusion component 59b, the diffusion component 59b is dispersed not only in the plane direction but also in the thickness direction. For this reason, the light incident on the light diffusion layer 51a collides with the diffusion component 59b at least once and changes its traveling direction with a high probability. Further, as described above, the resin material forming the main portion 59a, the thickness of the main portion 59a, the configuration (shape, size (particle size), refractive index, etc.) of the diffusing component 59b, the concentration of the diffusing component 59b, etc. are set as appropriate. By doing so, the degree of the light diffusion function of the light diffusion layer 51a can be adjusted within a very wide range.

  As described above, the light from the surface light source device 20 can be diffused to some extent by the light diffusion layer 51 a of the deflection optical sheet 50. Thereby, it is possible to smoothly change the angular distribution of luminance after the light is condensed by the first unit optical element 35 of the light guide optical sheet and the second unit optical element 60 of the deflection optical sheet 50. .

  The light diffused by the light diffusion layer 51 a of the deflecting optical sheet 50 is then directed to the polarizer 41, the liquid crystal cell 11, and the upper polarizing plate 12 of the lower polarizing plate 40 disposed on the light output side of the deflecting optical sheet 50. Become. At this time, the liquid crystal cell 11 selectively transmits light for each pixel, so that an observer of the display device 10 can observe an image.

  As described above, according to the optical module 20 incorporated in the display device 10 according to the present embodiment, the position where the light emitting unit 26 forming the light source 25 is shifted from the display region in the first direction d1 in the front direction nd observation. Even if the light source 25 does not depend on the light guide plate A (see FIG. 25) and the light source 25 is provided only on one side in the first direction d1, the light amount distribution along the first direction d1. Can be made sufficiently uniform. Thereby, a light guide plate can be excluded from the optical module 20 and the display apparatus 10, and the malfunction resulting from presence of a light guide plate can be eliminated. That is, it is possible to reduce the cost of the light guide plate, which is expensive due to the large thickness. In addition, a special support structure for supporting the light guide plate, which may be necessary due to the large thickness, can be eliminated from the optical module 20 and the display device 10. Furthermore, by eliminating the light guide plate, the optical module 20 and the display device 10 can be reduced in thickness and weight.

  Various modifications can be made to the above-described embodiment. Hereinafter, an example of modification will be described with reference to the drawings as appropriate. In the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above-described embodiment are used, and redundant descriptions are omitted.

  In the above-described embodiment, the deflecting optical sheet 50 includes a main part 59a made of a resin material, a light diffusion layer 51a made of a diffusion component 59b dispersed in the main part 59a, and a resin material only without containing the diffusion component 59b. And a resin layer 51b made of In other words, the diffusion component 59b is dispersed only in a part of the deflection optical sheet 50. However, the diffusing component 59b may be dispersed throughout the deflection optical sheet 50. In such an example, the deflecting optical sheet 50 is composed of only a light diffusion layer 51a having a main portion 59a made of a resin material and a diffusion component 59b dispersed in the main portion 59a. The second unit optical element 60 is configured as a part of the light diffusion layer 51a. In this case, the degree of the light diffusion function of the deflecting optical sheet 50 can be further freely adjusted.

  On the other hand, it is necessary to impart a light diffusing function to the deflecting optical sheet 50 in accordance with optical characteristics required for the optical module 20 and the display device 10, configurations of other components of the optical module 20 and the display device 10, and the like. Absent. That is, the diffusing component 59b may not be dispersed in the deflecting optical sheet 50, and the deflecting optical sheet 50 may be configured only by the resin layer 51b made of only the resin material.

  Furthermore, in the above-described embodiment, the example in which the cross-sectional shape of the main cutting surface of the second unit optical element 60 of the deflecting optical sheet 50 is a triangular shape has been described. The cross-sectional shape of the main cutting surface of the two-unit optical element 60 can be designed in various shapes. For example, the top of the triangular shape that forms the cross-sectional shape of the second unit optical element 60 on the main cut surface of the deflecting optical sheet 50 may be chamfered. Further, as indicated by a two-dot chain line in FIG. 2, at least one of the two sides extending from the above-described triangular second main body portion 55 bulges outward on the main cut surface of the deflecting optical sheet. You may deform | transform so that it may become a curve.

  Furthermore, as shown in FIG. 6, the second unit optical element 60 may have a curved outer contour on the main cut surface of the deflecting optical sheet 50. That is, the light incident surface of the second unit optical element 60 may be configured as a curved surface. As an example of a specific shape, the second unit optical element 60 corresponds to a part of an ellipse (a semi-ellipse as an example) or a part of a circle (a semi-circle as an example) on the main cut surface of the deflecting optical sheet 50. You may make it have a shape. Furthermore, as shown in FIG. 7, the second unit optical element 60 may have a shape obtained by removing the above-described triangular top portion of the main cutting surface on the main cutting surface of the deflection optical sheet 50. As an example of a specific shape, the second unit optical element 60 may have an isosceles trapezoidal shape as shown in FIG. You may make it have the shape formed by changing the upper base of trapezoid shape into a curve. The deflection optical sheet 50 shown in FIGS. 6 and 7 can be produced by extrusion molding in the same manner as the deflection optical sheet 50 of the above-described embodiment.

  8 and 9 show a modification of the second unit optical element 60 included in the deflection optical element 50. FIG. Here, this modified example will be described with reference to FIGS. 8 and FIG. 9 differs from the above-described embodiment only in the cross-sectional shape of the second unit optical element 60, and other modifications such as the arrangement of the second unit optical element 60, etc. The configuration can be the same.

  The outer contour 62 of the second unit optical element 60 described here has a shape formed by connecting a plurality of different parabolas in a cross section orthogonal to the longitudinal direction. In particular, in the example shown in FIGS. 8 and 9, the outer contour 62 of the second unit optical element 60 in the cross section perpendicular to the longitudinal direction of the second unit optical element 60 (the cross section corresponding to the main cutting surface described above) is The top portion 61a that is farthest from the second main body portion 55 and the base end portion 61b side that is connected to the second main body portion 55 are divided and extend along two different parabolas. Specifically, the top side section 62a including the top 61a of the outer contour 62 of the second unit optical element 60 as the center extends along the parabola P1, and the proximal end of the outer contour of the second unit optical element 60 A pair of base end side sections 62b including the portion 61b extends along the parabola P2.

  According to this configuration, the intersection 61c of the parabola P1 and the parabola P2 exists between the top part 61a and the base end part 61b on the outer contour 62 of the second unit optical element 60. The intact intersection defined by the parabola P1 and the parabola P2 is a pointed outside point that cannot be differentiated, but from the viewpoint of smoothing the angular distribution of luminance, it is in a region including the intersection of the parabola P1 and the parabola P2. The outer contour 62 of the second unit optical element 60 is connected to the parabola P1 and the parabola P2 in a differentiable manner, for example, a part of a circle, an ellipse, a parabola, a hyperbola, a spline curve, etc. You may make it extend along.

  In addition, the range of the line segment which connects the parabola P1 and the parabola P2 can be 50% or less of the height H2 of the 2nd unit optical element 60 in a front direction. And, "the outer contour of the second unit optical element extends along the parabola" means that the outer contour of the second unit optical element smoothly connects the two parabolas at the connection part of two different parabolas. In order to do so, it includes extending along a line segment other than the parabola in a range that is 50% or less of the height H2 of the second unit optical element 60 in the front direction.

Next, the parabolas P1 and P2 that define the outer contour 62 of the second unit optical element 60 shown in FIGS. 8 and 9 will be described. First, as shown in FIG. 9, in a cross section along the longitudinal direction of the second unit optical element 60, an X axis parallel to the light incident side surface 55b of the second main body portion 55 and a Z axis orthogonal to the X axis are shown. Define the coordinate axes used. In the coordinate system defined by the X axis and the Z axis, the position of the top portion 61a of the second unit optical element 60 is the origin O of the X axis and the Z axis, and the second main body 55 side as viewed from the origin O. Is the negative side of the Z-axis. When this coordinate system is used, the parabola P1 defining the top side section 62a is represented by “Z = −aX ² ”, and the parabola P2 defining the base end side section 62b is “Z = −bX ² + h”. Is represented. Here, “a”, “b”, and “h” in the formula satisfy the following formulas (x) and (y).
0 <a <b Formula (x)
0 <h Formula (y)
As an example, when the second unit optical element 60 is designed with the units of the variables “X” and “Y” in the parabolas P1 and P2 being [μm], the coefficient a of the function representing the parabola P1 is set to 0.01 or more and 0. A numerical value in the range of 0.06 or less, for example, 0.02. Similarly, when designing the second unit optical element 60 with the units of the variables “X” and “Y” in the parabolas P1 and P2 being [μm], the coefficient b of the function representing the parabola P2 is set to 0.01 or more and 0. A numerical value in the range of .06 or less, for example, 0.05.

An intersection 61c between the parabola P1 and the parabola P2 is the height H2 of the second unit optical element 60 along the front direction nd from the light incident side surface 55b of the second main body 55 in the Z-axis direction (in the front direction). You may make it locate in the range of 25-75%. The coefficient h in the function that specifies the parabola P2 is set so that the parabola P1 and the parabola P2 intersect each other.
The position of the intersection between the parabolas can be changed by the values of the coefficients a, b, and h in the function specifying the parabola P1 and the parabola P2.

  Further, the cross-sectional shape of the second unit optical element 60 shown in FIGS. 8 and 9 is such that the width W2 and the height H2 of the second unit optical element 60 satisfy “(W2) / 2 ≧ (H2)”. It is preferable that it is set to. However, from the viewpoint of securing a wide viewing angle, the cross-sectional shape of the second unit optical element 60 shown in FIGS. 8 and 9 is such that the width W2 and the height H2 of the second unit optical element 60 are “(W2)”. / 2 ≦ (H2) ”is preferably set. The second unit optical elements 60 are preferably arranged without gaps from the viewpoint of preventing omissions. In this case, the arrangement pitch of the second unit optical elements 60 and the width W2 of the second unit optical elements 60 are equal. Become.

  As an example of the dimensions of the second unit optical element shown in FIGS. 8 and 9 as described above, the width W2 can be 20 to 200 μm and the height H2 can be 10 to 100 μm.

  The “parabola” for specifying the contour outside the cross section of the second unit optical element shown in FIGS. 8 and 9 is not limited to a parabola in a strict sense as a mathematical concept. A parabola in the strict sense with a slight modulation is also included in the parabola here. For example, (1) a tangential approximation of a parabola in a strict sense, specifically, (1-1) discrete points (preferably 10 or more) arranged on a parabola, adjacent points (1-2) A polygon inscribed in a parabola (preferably a decagon or more). (1-3) Polygon circumscribing the parabola (preferably a decagon or more); (2) The parabola is slightly displaced by deformation in one or all sections of the parabola (preferably within 5% of each coordinate value). A curved line, and the like. The deflection optical sheet including the second unit optical element specified by the strict parabola-modulated line is an optical element of the deflection optical sheet including the second unit optical element specified by the strict parabola. When the characteristic and optical action have optical characteristics and optical action that are not significantly different from each other in practice, a line obtained by modulating a parabola in a strict sense is regarded as a “parabola”.

  According to the deflection optical sheet 50 shown in FIGS. 8 and 9 as described above, since the outer cross-sectional contour of the second unit optical element 60 is defined by a plurality of parabolas, the luminance in the front direction is appropriately maintained. However, the viewing angle can be further expanded.

  Next, other deformability will be described. In the above-described embodiment, an example in which the deflection optical sheet 50 is made of an extruded material obtained by extrusion molding is shown, but the present invention is not limited to this. It is also possible to use a deflecting optical sheet manufactured by other manufacturing methods such as injection molding. Here, in FIGS. 10 to 13, as an example, an example of a deflecting optical sheet 50 that can be produced by molding a resin applied on the base film 53, for example, ionizing radiation, into a desired shape is shown. ing. The deflection optical sheet 50 shown in FIG. 10 can be produced by molding a resin containing a diffusion component 59b on the base film 53. In the deflection optical sheet 50 shown in FIG. 10, the second unit optical element 60 forming the light incident side surface 50b is formed as a part of the light diffusion layer 51a, and the base film 53 is formed on the light output side of the light diffusion layer 51a. A resin layer 51b is provided.

  The deflection optical sheet 50 shown in FIG. 11 can be produced by molding a resin on the base film 53 that contains the diffusion component 59b and forms the light diffusion layer 51a. For example, an extruded material can be used as the base film 53 including the diffusion component 59b, and the base film 53 constitutes the light diffusion layer 51a.

  In the example shown in FIG. 12, the second unit optical element 60 is formed by molding a resin on the base film 53, but the second unit optical element 60 of the base film 53 is formed. A mat layer 54 having an uneven surface is formed on the light exit side surface 50a. The mat layer 54 is composed of a diffusion component 59b and a resin material that functions as a binder resin (for example, an ionizing radiation resin). The resin material as the binder resin functions as the main portion 59a, so that the light diffusion layer is formed. 51a is configured. The mat layer 54 can be formed on the base film 53 either before or after the second unit optical element 60 is molded.

  In the example shown in FIG. 13, a mat layer composed of a diffusion component 59b and a resin material (main portion 59a) functioning as a binder resin between the base film 53 and the resin material forming the second unit optical element 60. 54 is formed. In the aspect shown in FIG. 13, the mat layer 54 is formed on the base film 53, and the second unit optical element 60 is shaped on the mat layer 54.

  In addition, when forming the deflection | deviation optical sheet 50 by shape | molding the resin apply | coated on the base film 53, the resin apply | coated on the base film 53 is shown in FIGS. In addition to the plurality of second unit optical elements 60, a land portion 52 that is disposed between the base film 53 and the second unit optical element 60 and covers the base film 53 may be formed. In this case, the land portion 52 constitutes a part of the second main body portion 55 of the deflection optical sheet 50.

  The second unit optical element 60 is not limited to a linear element arranged one-dimensionally, but may be a dot-like element arranged two-dimensionally to constitute a microlens (fly eye lens).

  Furthermore, the light diffusion function of the deflecting optical sheet 50 in the above-described embodiment may be an isotropic light diffusion function or an anisotropic light diffusion function. When the deflection optical sheet 50 has an anisotropic light diffusion function, the deflection optical sheet 50 may exhibit a stronger light diffusion function in the second direction d2 than in the first direction d1, or in the second direction. A stronger light diffusion function may be exhibited in the first direction d1 than in d2. Furthermore, the deflection optical sheet 50 may exhibit the strongest light diffusion function in directions other than the first direction d1 and the second direction d2. According to such a configuration, for example, optical characteristics (for example, viewing angle characteristics) required for the display device 10 can be realized with a higher degree of freedom.

  As an example, as shown in FIG. 14, the diffusion component 59b having the longitudinal direction ld is arranged in the light diffusion layer 51a of the deflecting optical sheet 50 so as to have an orientation in a predetermined direction od. An isotropic light diffusion function can be imparted to the deflecting optical sheet 50. Here, the longitudinal direction of the diffusion component 59b can be specified as the direction in which the target diffusion component 59b has the longest length. Further, “the diffusion component 59b having the longitudinal direction ld has an orientation in the predetermined direction od” means that the angle formed by the longitudinal direction ld of each diffusion component 59b with respect to the predetermined direction od is 0 ° or more and 45 This means that the diffusion component 59b is arranged with directional regularity with reference to the predetermined direction od.

  The light diffusion layer 51a of the deflecting optical sheet 50 shown in FIG. 14 is manufactured by extruding a diffusion component 59b having a longitudinal direction as a raw material together with a resin material that forms the main portion 59a. obtain. The diffusion component 59b having the longitudinal direction is directed so that the longitudinal direction ld is along the extrusion direction (machine direction) under high pressure when passing through the die of the extruder together with the resin material. Thereby, the diffusion component 59b in the extruded material is dispersed in the deflection optical sheet 50 so as to have an orientation in a specific direction od.

  As the shape of the diffusing component 59b having the longitudinal direction ld, various shapes such as a plate shape, a granular shape (rice granular shape), a needle shape, a scale shape, and a fine plate shape can be adopted as an example. As a specific example, the average aspect ratio (the average value of the ratio of the length of the diffusion component 59b along the longitudinal direction ld to the length of the diffusion component 59b along the direction orthogonal to the longitudinal direction ld) is And bubbles having an average particle size of 1.5 to 50 μm and an average particle size of the diffusing component 59b (particle size calculated by the volume equivalent method, ie, arithmetic average of volume equivalent diameter, the same applies hereinafter) of 0.5 μm to 100 μm The diffusion component 59b having the longitudinal direction ld can be used. Moreover, the diffusion component 59b which consists of heat resistant organic fibers, such as the diffusion component 59b which consists of organic fibers, for example, an aramid fiber, a wholly aromatic polyester fiber, a polyimide fiber, can also be used. Moreover, the diffusion component 59b which consists of fibrous fillers, such as glass fiber, a silica fiber, an alumina fiber, a zirconia fiber, for example can also be used for the diffusion component 59b which consists of inorganic fibers. Furthermore, a diffusion component 59b made of a thin plate filler (mica) can also be used. Furthermore, a diffusing component 59b made of an amorphous filler, for example, a diffusing component 59b made of an inorganic white pigment such as silica, calcium carbonate, magnesium hydroxide, clay, talc, or titanium dioxide can be used.

  The diffusion component 59b having the longitudinal direction ld exhibits a stronger light diffusion function in a direction perpendicular to the longitudinal direction than in a direction parallel to the longitudinal direction. For example, in the embodiment described above, the light source 25 is configured by arranging a large number of light emitting units 26 in the second direction d2. The brightness distribution along the second direction d2 is influenced by the configuration of the light source 25a, for example, the arrangement pitch of the light emitting units 26.

  Therefore, in the above-described embodiment, when the distribution of brightness along the second direction d2 is sufficiently uniformed by the configuration of the light source 25, it is preferable to mainly diffuse in the first direction d1. From this point, it is preferable that the orientation direction od of the diffusing component 59b having the longitudinal direction ld is parallel to the second direction which is the arrangement direction of the light emitting units 26 forming the light source 25. In this case, it is possible to effectively prevent the light incident on the deflecting optical sheet 50 from being diffused more than necessary, and to effectively use the light.

  On the other hand, when the number of the light emitting units 26 is small, uneven brightness may occur along the second direction d2. In this case, the orientation direction od of the diffusing component 59b having the longitudinal direction ld is parallel to the first direction d1 orthogonal to the second direction d2 in which the light emitting portions 26 forming the light source 25 are arranged, and the diffusing component 59b is It is preferable to diffuse mainly in two directions d2. When the light diffusing layer 51a of the optical sheet 50 has an anisotropic diffusing function that exhibits a stronger light diffusing ability in the second direction d2 perpendicular to the first direction d2 than the light diffusing ability in the first direction d1. In other words, the light component along the second direction d2 is intensively diffused while maintaining the traveling direction of the light component along the first direction d1 collected by the second unit optical element 60. it can. Thereby, while increasing the luminance in the front direction by the light collecting function caused by the second unit optical element 60, at the same time, according to the configuration (array) of the light emitting unit 26 by the anisotropic diffusion function caused by the light diffusion layer 51a. It is also possible to eliminate variations in brightness.

  Furthermore, in the above-described embodiment, the example in which the deflection optical sheet 50 is bonded to the polarizer 41 by water bonding is shown, but the present invention is not limited to this, and the adhesive layer is interposed between the deflection optical sheet 50 and the polarizer 41. It may be arranged. In this modification, the adhesive layer may include an adhesive and a diffusion component dispersed in the adhesive. In this case, the degree of the light diffusion function by the adhesive layer can be appropriately adjusted independently of the presence or absence of the light diffusion function in the deflection optical sheet 50 or the degree of the light diffusion function of the deflection optical sheet 50. Thereby, the degree of the light diffusion function that the lower polarizing plate 40 can exhibit can be designed more freely. In addition, what was illustrated as the diffusion component 59b which can be contained in the light guide optical sheet 30 and the deflection | deviation optical sheet 50 can be similarly used for the diffusion component contained in a contact bonding layer. In addition, the degree of the light diffusion function by the adhesive layer can be appropriately adjusted by the same method as the degree of the light diffusion function in the deflection optical sheet 50. Furthermore, the light diffusing function of the adhesive layer may be isotropic or anisotropic. When the light diffusion function of the adhesive layer is anisotropic, the adhesive layer has the strongest light in any direction other than the first direction d1, the second direction d2, the first direction d1, and the second direction d2. You may make it exhibit a spreading | diffusion function.

  Furthermore, in the above-described embodiment, an example in which the lower polarizing plate 40 includes the polarizer 41 and the functioning deflection optical sheet 50 bonded to the polarizer 41 from the light incident side is shown. I can't. For example, a protective sheet made of a TAC film or the like may be provided on the light output side of the polarizer 41. In addition, a phase difference plate for compensating for the phase difference of light may be provided between the lower polarizing plate 40 and the liquid crystal cell 11, but in this case, the protective sheet on the light output side of the lower polarizing plate 40 is You may make it also serve as the protective sheet of the light-incidence side of a phase difference plate.

  In addition, as an intermediate film between the deflecting optical sheet 50 and the polarizer 41, a polarization separation film having a function of transmitting a specific polarization component and reflecting other polarization components back to the light source side is provided. It may be. According to this example, by providing the polarization separation film, light of a polarization component that can be transmitted through the polarizer 41 can be selectively incident on the polarizer 41 and other light can be returned to the light source side. The light returned to the light source side can be incident again on the polarization separation film while changing the polarization state by subsequent reflection or the like. “DBEF” (registered trademark) available from 3M USA can be used as a polarized light separation film that can be useful for improving luminance. In addition to “DBEF”, a high-intensity polarizing sheet “WRPS” available from Shinwha Intertek, Korea, a wire grid polarizer, or the like can be used as the polarization separation film.

  Furthermore, a light diffusing sheet having a light diffusing function may be provided as an intermediate film between the polarizer 41 of the lower polarizing plate 40 and the deflecting optical sheet 50, or a simple resin film, for example, a pair A triacetyl cellulose film (TAC film) having a parallel main surface may be provided.

  Various modifications can be made to the light guide optical sheet 30. In the embodiment described above, the example in which the first unit optical element 35 protrudes from the first main body portion 31 toward the deflecting optical sheet 50 has been described. However, as shown in FIG. 15, the linear first unit optical element 35 extending in the first direction d <b> 1 is provided on the light incident side surface 31 b of the first main body portion 31 and protrudes toward the reflection sheet 21. It may be. In the example shown in FIG. 15 as well, the first unit optical element 35 provided on the light incident side surface 31b of the first main body 31 and extending in the first direction d1 exhibits a light guiding function in the first direction d1. be able to.

  Moreover, although the light guide optical sheet 30 has shown the example which exhibited the light extraction function by containing the light-diffusion component 34 as a light extraction element, it is not restricted to this. For example, in addition to the light guide optical sheet 30 containing the light diffusing component 34 or instead of the light guide optical sheet 30 containing the light diffusing component 34, another configuration (light extraction element) may be used as the light guide optical sheet. For example, the surface of the light guide optical sheet 30 on which the first unit optical element 35 is not provided is a slope inclined with respect to the first direction d1, or the light guide optical The light guide optical sheet 30 may be provided with a light extraction function by roughening the surface of the sheet 30 on which the first unit optical element 35 is not provided.

  Further, the light guide optical sheet 30 can be variously changed in the same manner as the deflection optical sheet 50. For example, the diffusion component 34 of the light guide optical sheet 30 can change the position, configuration, and the like contained in the sheet, similarly to the diffusion component 59a of the deflection optical sheet 50. In addition, the first unit optical element 35 of the light guide optical sheet 30 can change its cross-sectional shape and the like, similarly to the second unit optical element 60 of the deflection optical sheet 50. Further, as the method for manufacturing the light guide optical sheet 30, a method other than extrusion molding can be adopted as in the second unit optical element 60 of the deflecting optical sheet 50. Further, the layer configuration of the light guide optical sheet 30 can be changed in the same manner as the deflection optical sheet 50.

  In the embodiment described above, an example in which the light guide optical sheet 30 is not joined to the deflection optical sheet 50 has been shown. However, the light guide optical sheet 30 may be joined to the deflecting optical sheet 50 via an appropriate means such as an adhesive layer. In this case, in the optical module 20, the light guide optical sheet 30 is fixed to the deflecting optical sheet 50 in a positioned state without requiring a special member, structure, mechanism, or the like for supporting the light guide optical sheet 30. It becomes possible.

  16 to 19 show an example in which the light guide optical sheet 30 and the deflecting optical sheet 50 are joined in the same cross section as FIG. 16 to 19, the first unit optical element 35 of the light guide optical sheet 30 is incident on the light incident side (reflective sheet) from the first main body 31 as in the modification shown in FIG. 15. 21 side). In the example shown in FIG. 16, the adhesive layer 39 is provided on the light output side surface 30 a of the light guide optical sheet 30, and the top of the second unit optical element 60 of the deflecting optical sheet 50 is in contact with the adhesive layer 39. Is sticking. That is, the deflection optical sheet 50 is bonded to the light guide optical sheet 30 through the top of the second unit optical element 60.

  On the other hand, in the example shown in FIGS. 17 to 19, spacers 63, 64, and 38 are provided between the deflecting optical sheet 50 and the light guide optical sheet 30. The deflection optical sheet 50 and the light guide optical sheet 30 are bonded. As a result, a sufficient gap is formed between the deflection optical sheet 50 and the light guide optical sheet 30, and the top of the second unit optical element 60 of the deflection optical sheet 50 is exposed away from the light guide optical sheet 30. Yes. For this reason, the second unit optical element 60 can sufficiently exhibit the expected optical function.

  In the example shown in FIG. 17, the adhesive layer 39 is provided on the light exit side surface 30 a of the light guide optical sheet 30, and the second unit is formed on the light entrance side surface 55 b of the second main body portion 55 of the deflection optical sheet 50. A spacer (projection) 63 having a height higher than that of the optical element 60 is provided. Then, the top of the spacer 63 comes into contact with the adhesive layer 39, whereby the deflection optical sheet 50 is bonded to the light guide optical sheet 30 through the top of the spacer (projection) 63.

  In the example shown in FIG. 18, an optical function is positively imparted to the spacer 64. That is, in the example shown in FIG. 18, the deflection optical sheet 50 includes the second main body portion 55 and the linear second unit optical elements 60 arranged one-dimensionally on the light incident side surface 55 b of the second main body portion 55. And further unit optical elements 64 two-dimensionally arranged on the light incident side surface 55b of the second main body 55. The further unit optical element 64 is higher than the second unit optical element 60 and protrudes from the second main body portion 55 to constitute a fly-eye lens on the second main body portion 55. The example shown in FIG. 18 (for example, a light collecting function or a light diffusion function) can be exhibited.

  On the other hand, in the example shown in FIG. 19, a granular spacer 38 having a size that does not enter between the unit optical elements is provided between the light guide optical sheet 30 and the deflecting optical sheet 50. Adhesive 38 a is attached around 38. The light guide optical sheet 30 and the deflection optical sheet 50 are in contact with the adhesive 38a on the granular spacer 38, and the light guide optical sheet 30 and the deflection optical sheet 50 are bonded to each other.

  Further, various changes can be made to the reflection sheet 21. For example, in the above-described embodiment, the example in which the reflection sheet 21 has the flat reflection surface 22 parallel to the light guide optical sheet 30 has been described. For example, as in the example shown in FIG. 20, the light incident side surface 31 b of the first main body portion 31 from the reflection surface 22 of the reflection sheet 21 to the light incident side surface 31 b of the first main body portion 31 of the light guide optical sheet 30. The distance sd along the normal direction to is changed so as to decrease from the one edge portion 30c1 side (one side) toward the other edge portion 30c2 side (the other side) in the first direction d1. Also good. According to such a modified example, the density of light incident on the liquid crystal display panel 15 is increased in a region away from the light emitting unit 26 that tends to reduce the amount of light, that is, in a region on the other side in the first direction d1. Can be made. Thereby, the distribution of the amount of light incident on each position along the first direction d1 of the liquid crystal display panel 15 can be made uniform. In addition, it is effective that the light emitted from the light emitting unit 26 leaks from between the reflection sheet 21 and the light guide optical sheet 30 on the other side in the first direction d1 and cannot be used for image formation. Can be prevented. Therefore, the utilization efficiency of the light emitted from the light emitting unit 26 can be effectively increased.

  In the modification shown in FIG. 20, the light incident side surface 31b of the first main body 31 of the light guide optical sheet 30 is configured as a flat surface. On the other hand, a region on one side of the reflecting surface 22 of the reflecting sheet 21 in the first direction d1 is formed as a flat surface parallel to the light incident side surface 31b of the first main body 31, and the reflecting surface of the reflecting sheet 21 is formed. The other area | region of 22 is formed as a curved surface. However, from the viewpoint of changing the distance sd from the reflection surface 22 of the reflection sheet 21 to the first main body portion 31 of the light guide optical sheet 30, the reflection surface 22 of the reflection sheet 21 is the first main body of the light guide optical sheet 30. It may be configured only from a flat surface arranged to be inclined with respect to the light incident side surface 31b of the part 31, or the entire area of the reflective surface 22 of the reflective sheet 21 may be configured as a curved surface, Furthermore, the reflection surface 22 of the reflection sheet 21 may be configured as a bent surface.

  Furthermore, as already mentioned, the reflection sheet 21 may have a diffuse reflection function (a diffuse reflection function, a scattering reflection function) instead of the regular reflection function. Further, when the reflection sheet 21 has a diffuse reflection function, the diffusion by reflection on the reflection sheet 21 may be isotropic diffusion or anisotropic diffusion. When the diffuse reflection function of the reflection sheet 21 is an anisotropic diffuse reflection function, the reflection sheet 21 is any one other than the first direction d1, the second direction d2, the first direction d1, and the second direction d2. You may make it exhibit the strongest diffuse reflection function in a direction.

  Furthermore, in the above-described embodiment, the light emitted from the light emitting unit 26 of the light source 25 is directly incident on the light guide optical sheet 30 or the reflection sheet 21, that is, emitted from the light emitting unit 26 of the light source 25. Although the example which light injects into the light guide optical sheet 30 or the reflection sheet 21 without passing through another member was shown, it is not restricted to this example. As shown in FIGS. 26 to 28, an optical element 84 that receives light emitted from the light emitting unit 26 of the light source 25 and directs it toward the reflection sheet 21 may be provided. The optical element 84 is used for various purposes, for example, to direct the traveling direction of light emitted from the light emitting unit toward the reflecting sheet 21, or to direct only to the reflecting sheet 21, or to directivity characteristics of the light emitting unit 26. For the purpose of adjusting the light quantity distribution of light incident on each position of the light guide optical sheet 30 or the reflection sheet 21 by eliminating or correcting (light distribution characteristics, in other words, the angle (direction) distribution of luminous intensity). Can be provided. As shown in FIGS. 26 to 28, a lens, a prism, a reflection mirror, or the like is used as the optical element 84 for changing the traveling direction of light from the light emitting unit 26 or adjusting the directivity characteristics of the light emitting unit 26. it can. In addition, the optical element formed of the reflecting mirror may have a curved reflecting surface as shown in FIGS. 26 and 27, or may have a flat reflecting surface. Further, when the light emitting units 26 are arranged in the second direction d2 or when the light emitting units 26 extend along the second direction d2, the optical element may also extend in the second direction d2. Alternatively, a plurality of optical elements may be arranged in the second direction d2.

  As an example, in the example shown in FIG. 23, the light source 25 is arranged on the base 81 extending along the second direction d2 (the depth direction of the paper surface in FIG. 23) and on the base 81 along the second direction d2. And a plurality of light emitters 26 and an optical element 85 extending along the second direction d2. The light emitted from the light emitter 26 passes through the optical element 85 and proceeds to a region between the light guide optical sheet 30 and the reflection sheet 21. In the example shown in FIG. 23, the space between the base 81 and the optical element 85 is surrounded by the reflective sheet 21 and the reflective material 83 disposed at a position facing the reflective sheet 21 from the front direction. Thus, the light emitted from the light emitter 26 is prevented from leaking in an unintended direction.

  In the example shown in FIG. 23, the optical element 85 may have a unit optical element such as a unit lens or a unit prism. For example, the optical element 85 may have a large number of unit optical elements arranged along the second direction d2. When the unit optical elements of the optical element 85 extend in a direction orthogonal to the arrangement direction (second direction d2), that is, in the direction connecting the light guide optical sheet 30 and the reflection sheet 21, the optical element 85 is The brightness distribution along the second direction d2 can be adjusted. In other words, the optical element 85 can make the unevenness of brightness caused by the arrangement of the light emitters 26, for example, the light and dark unevenness appearing in a striped pattern inconspicuous. As the cross-sectional shape of the unit optical elements provided in the optical element 85, various shapes can be adopted. As an example, the unit optical elements having the cross-sectional shapes shown in FIGS. 8 and 9 are arranged at a pitch of 50 μm. An optical element 85 can be used.

  In the example shown in FIG. 23, in the cross section orthogonal to the second direction d2, that is, on the main cut surface of the deflection optical sheet, the reflection sheet side end of the optical element 85 is the light guide optical of the optical element 85. It is located outward along the first direction d1 from the sheet side end. In other words, the normal line direction of the optical element 85 is inclined so as to face the reflective sheet 21 side with respect to the first direction d1. Although the illustrated inclination of the optical element 85 is merely an example, the direction of the optical axis pd of the light emitted from the light source 25 can be adjusted by adjusting the direction of the optical element 85. When the present inventors repeated the experiment, when the normal direction of the optical element 85 is directed toward the reflection sheet 21 with respect to the first direction d1, the optical axis pd of the light emitted from the light source 25 is the reflection sheet 21. When the normal direction of the optical element 85 is directed toward the light guide optical sheet 30 with respect to the first direction d1, the optical axis pd of the light emitted from the light source 25 is guided. There was a tendency for the optical sheet 30 to be easily oriented.

  In the above description, an example in which the unit optical element of the optical element 85 forms a lenticular lens is shown. However, the present invention is not limited to this, and elements that can exhibit various optical functions can be used. These unit optical elements may be two-dimensionally arranged to constitute a fly-eye lens (microlens).

  As another example, the optical element 85 extending in the second direction d2 has a function of transmitting a specific polarization component and reflecting the other polarization component to return to the light emitter 26 again. A polarization separation film may be used. At this time, the optical element 85 configured as a reflective polarization separation film is configured to transmit a polarization component that can be transmitted by the polarizer 41. For example, when the transmission axis of the polarizer 41 of the liquid crystal display panel 15 is parallel to the first direction d1, the transmission axis of the optical element 85 is set in the direction orthogonal to the second direction d2, that is, the light guide optics. What is necessary is just to make it the direction which connects the sheet | seat 30 and the reflective sheet 21. FIG. According to such a form, the light source 25 itself exhibits a light recycling function, and the light use efficiency in the optical module 20 can be improved. Moreover, according to such a form, compared with the case where a reflection type polarization separation film is arrange | positioned in parallel with the polarizer 41 of the liquid crystal display panel 15, the usage area of a comparatively expensive polarization separation sheet is decreased. be able to. As the reflective polarization separation film, “DBEF” (registered trademark) available from 3M USA can be used. In addition to “DBEF”, a high-intensity polarizing sheet “WRPS” available from Shinwha Intertek, Korea, a wire grid polarizer, or the like can be used as the polarization separation film.

  In the example shown in FIG. 23, the auxiliary reflection sheet 23 is provided at a position facing the light source 25 along the first direction d1. In the example shown in FIG. 23, in the cross section orthogonal to the second direction d2, that is, on the main cut surface of the deflection optical sheet, the reflection sheet side end of the auxiliary reflection sheet 23 is the light guide optical of the auxiliary reflection sheet 23. It is located inward along the first direction d1 from the sheet side end. In other words, the normal direction of the auxiliary reflection sheet 23 is inclined so as to face the light guide optical sheet 30 side with respect to the first direction d1, and the reflected light is directed to the light guide optical sheet 30 side. It has become.

  As another example, the light source 25 may be provided with two or more optical elements. For example, an optical element having a unit optical element and an optical element made of a reflective polarization separation film may be incorporated in one light source 25.

  Furthermore, a modified example regarding the light source 25 will be described. In the above-described embodiment, the optical axis pd of the light emitting unit 26 is positioned on the light incident side surface 30 b of the light guide optical sheet 30. However, in the cross section along both the normal direction to the sheet surface of the light guide optical sheet 30 and the first direction d1, the optical axis pd of the light emitting unit 26 is a direction parallel to the sheet surface of the light guide optical sheet 30. May be inclined from the light guide optical sheet 30 side toward the reflection sheet 21 side. Further, the optical axis pd of the light emitting unit 26 may be positioned on the reflection surface 22 of the reflection sheet 21.

  Moreover, in embodiment mentioned above, although LED was illustrated as the point light emission part 26 of the light source 25, it is not restricted to this, You may use another point light emission part. For example, a laser light source that generates laser light may be used as the point light emitting unit. In the above-described embodiment, as shown in FIG. 3, an example in which the light emitting units 26 are arranged side by side along the entire length of one edge of the liquid crystal display panel 15 has been described. Without being limited thereto, the number of light emitting units 26 forming the light source 25 can be reduced. Further, the light emitting unit 26 of the light source 25 is not limited to the point light emitting unit, and for example, a linear light emitting unit such as a cold cathode tube may be used.

  In the above-described embodiment, in the first direction d1, light that is directed from one edge 30c1 side (one side) of the light guide optical sheet 30 to the other edge 30c2 side (other side) is guided light. The example in which only the light source 25 that irradiates the region between the sheet 30 and the reflection sheet 21 is provided is shown. However, as shown in FIG. 21, in the first direction d1, light directed from the other edge 30c2 side (other side) of the light guide optical sheet 30 toward one edge 30c1 side (one side) is guided light. A second light source 27 that irradiates a region between the sheet 30 and the reflection sheet 21 may be further provided. That is, a pair of light sources 25 and 27 each having the light emitting unit 26 may be provided corresponding to both the edge portions 30c1 and 30c2 in the first direction of the light guide optical sheet 30.

  Further, in the above-described embodiment, the example in which the deflection optical sheet 50 is bonded to the polarizer 41 to form a part of the liquid crystal display panel 15 has been described, but the present invention is not limited thereto. The deflection optical sheet 50 may be provided separately from the liquid crystal display panel 15. In this example, an optical sheet such as a polarization separation film, an isotropic light diffusing sheet, an anisotropic isotropic light diffusing sheet, and a condensing sheet may be provided between the liquid crystal display panel 15 and the deflecting optical sheet 50. Further, in the above-described embodiment, the example in which the light guide optical sheet 30 is disposed at the position facing the deflecting optical sheet 50 in the front direction is shown, but the present invention is not limited thereto. Between the light guide optical sheet 30 and the deflecting optical sheet 50, an optical sheet such as a polarization separation film, an isotropic light diffusion sheet, an anisotropic light diffusion sheet, a light collecting sheet, or the like may be provided. Further, in the above-described embodiment, the example in which the reflection sheet 21 is disposed at the position facing the light guide optical sheet 30 in the front direction is shown, but the present invention is not limited thereto. Between the reflective sheet 21 and the light guide optical sheet 30, an optical sheet such as an isotropic light diffusing sheet, an anisotropic isotropic light diffusing sheet, and a light collecting sheet may be provided.

  Similarly, although the liquid crystal display panel has shown the example which consists of a pair of polarizing plates 12 and 40 and the liquid crystal cell 11 located between a pair of polarizing plates 12 and 40, it is not restricted to this. For example, various functional optical sheets such as an antireflection film, an antiglare film, an antistatic film, and a hard coat film may be provided on the liquid crystal display panel 15.

  As an example, FIG. 22 discloses an example in which the liquid crystal display panel 15 includes a light control member 70 disposed on the light output side of the upper polarizing plate 12. The light control member 70 is a member having a function of changing the traveling direction of light, and includes a light transmission part (main part) 71 and an intermediate part (filling part) 72. In the example shown in FIG. 22, the intermediate portion 72 is formed in a columnar shape and extends to the back / near side of the paper surface of FIG. 22. The light transmission part 71 is provided adjacent to both sides of the intermediate part 72 and has a substantially trapezoidal cross section and extends in a columnar shape.

  The light transmission part 71 is a part whose main function is to transmit light. As shown in FIG. 22, the trapezoidal cross section of the light transmitting portion 71 is arranged so that the long lower base faces the light incident side and the short upper base faces the light outgoing side. The light transmission parts 71 are arranged at predetermined intervals along the panel surface of the liquid crystal display panel 15. An intermediate portion 72 having a substantially triangular cross section is formed between two adjacent light transmission portions 71. Therefore, the cross-sectional triangular shape formed by the interspace 72 has a base on the upper base side of the cross-sectional trapezoidal shape formed by the light transmitting portion 71 and a vertex on the lower base side of the cross-sectional trapezoidal shape formed by the light transmitting portion 71. Have.

  Such a light control member can be manufactured as follows. First, an ionizing radiation curable resin is molded on the transparent base material 73 to form the light transmission part 71. Next, an intermediate portion 72 is formed by applying and curing an ionizing radiation curable resin between the light transmitting portions 71. As a result, the light control member 70 having the transparent base material 73 and the light transmission part 71 and the intermediate part 72 formed on the transparent base material 73 is obtained.

  The light control member 70 has a light diffusing function caused by reflection or refraction at the interface between the light transmitting portion 71 and the intermediate portion 72 by forming the light transmitting portion 71 and the intermediate portion 72 from materials having different refractive indexes. Will be expressed.

  The cross-sectional shape of the intermediate portion 72 can be changed to various shapes without being limited to the triangular shape, and the cross-sectional shape of the light transmitting portion 71 is changed from a trapezoidal shape according to the cross-sectional shape of the intermediate portion 72. It may be changed. For example, the cross-sectional shape of the intermediate portion 72 may be a trapezoidal shape, or the hypotenuse of the intermediate portion 72 forming the side portion of the trapezoidal cross-sectional shape may be a polygonal line or a curved line.

  Although several modifications to the above-described embodiment have been described above, a plurality of modifications can be applied in appropriate combination.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, this invention is not limited to this Example.

  The optical modules according to Example 1 and Example 2 and the optical modules according to Comparative Example 1 and Comparative Example 2 were actually produced, and the brightness distribution along the first direction was investigated. The optical modules according to Example 1, Example 2, and Comparative Example 1 were manufactured using a light source, a reflection sheet, a light guide optical sheet, and a deflection optical sheet. A light guide optical sheet was disposed on the back side of the deflecting optical sheet, and a reflection sheet was disposed on the back side of the light guide optical sheet. The light source is disposed only on one side along the first direction, and the light is projected onto a region between the light guide optical sheet and the reflection sheet along the first direction. Each optical module was configured to be identical to each other except for the configuration of the light guide optical sheet. In the optical module according to Example 1, the optical module according to Example 2, and the optical module according to Comparative Example 1, the same light guide optical sheet was used, but the arrangement of the light guide optical sheets was made different. On the other hand, in the optical module according to Comparative Example 2, no light guide optical sheet was provided.

  In the optical module according to Example 1, the light guide optical sheet described in the above embodiment was used. That is, in Example 1, the light guide optical sheet has a sheet-like first main body portion and a large number of first unit optical elements provided on the first main body portion. The first unit optical elements protrude from the first main body portion toward the deflecting optical sheet, extend linearly in the first direction, and are arranged without gaps in the second direction. On the main cut surface of the light guide optical sheet, the first unit optical element had an isosceles triangular shape with a width W1 of 50 μm and an apex angle θx of 90 °.

  On the other hand, in the optical module according to Example 2, the same light guide optical sheet as that of the optical module according to Example 1 was used. However, the light guide optical sheet was arranged so that the first unit optical element protruded toward the reflection sheet, as in the modification described with reference to FIG. That is, the optical module according to Example 2 was different from the optical module according to Example 1 in that the front and back directions of the light guide optical sheet were reversed.

  In the optical module according to Comparative Example 1, the same light guide optical sheet as that of the optical module according to Example 1 was used. The light guide optical sheet was arranged such that the first unit optical element protruded toward the deflecting optical sheet. However, the light guide optical sheet was arranged so that the first unit optical elements were arranged in the first direction and each first unit optical element extended along the second direction. In other words, the optical module according to Comparative Example 1 was different from the optical module according to Example 1 in that the light guide optical sheet was rotated 90 °.

  The length along the first direction of each optical module was about 400 mm, and the length along the second direction of each optical module was about 700 mm. The thickness along the front direction of each optical module was set to approximately 30 mm.

  The reflection sheet was a white resin film incorporated in a commercially available television receiver. Irregularities are formed on the reflection surface of the reflection sheet, and the diffusion component is dispersed inside the reflection sheet.

  The deflecting optical sheet was an optical sheet in which linear second unit optical elements having an isosceles triangular shape with a width W2 of 50 μm and an apex angle θy of 66 ° were linearly arranged without gaps. Like the deflection optical sheet shown in FIG. 5, this optical sheet is composed of a resin layer configured to include the second unit optical element, and a light diffusion layer positioned on the light output side of the resin layer. did.

  The light source included LEDs arranged side by side in the second direction and a cap covering the LEDs. The width along the second direction of the LED was 3 mm, and the width along the second direction of the cap was 23 mm. The LEDs were arranged at a pitch of 25 mm along the second direction. The auxiliary reflective element had a reflective surface made of a silver vapor deposited film. The optical axis of light emitted from a light source including an LED is directed in a direction parallel to the first direction. The auxiliary reflecting element was arranged so as to reflect the light incident from the direction along the optical axis of the LED toward the deflecting optical sheet.

  For the optical modules according to Example 1, Example 2, Comparative Example 1 and Comparative Example 2, the illuminance was measured at each position along the first direction on the light output side surface of the deflecting optical sheet. FIG. 24 is a graph showing the illuminance distribution along the first direction. In the graph of FIG. 24, the illuminance measured at each position along the first direction is shown as the illuminance ratio to the maximum illuminance measured for each optical module.

  In the optical modules according to Example 1 and Example 2, compared to the optical modules according to Comparative Example 1 and Comparative Example 2, the illuminance distribution along the first direction could be effectively made uniform.

DESCRIPTION OF SYMBOLS 10 Display apparatus 11 Liquid crystal cell 15 Liquid crystal display panel 20 Optical module 21 Reflective sheet 22 Reflective surface 23 Auxiliary reflective sheet 25 Light source 26 Light emission part 27 Light source 30 Light guide optical sheet, light guide film, optical sheet 31 Main-body part 31a Light emission side surface 31b In Light side surface 32a Light diffusing layer 32b Resin layer 33 Main portion 34 Diffusing component 35 First unit optical element 38 Spacer 38a Adhesive 39 Adhesive layer 40 Polarizing plate, lower polarizing plate 40b Light incident side surface 41 Polarizer 50 Polarizing optical sheet, protective film Optical sheet 50a Light exit side surface 50b Light entrance side surface 51a Light diffusion layer 51b Resin layer 52 Land portion 54 Mat layer 55 Second body portion 55a Light exit side surface 55b Light entrance side surface 59a Main portion 59b Diffusion component 60 Second unit optical element 61a Top portion 61b Base end 61c Intersection 62 Outer contour 62a Top side section 62b Base end side section 63 spacer 64 further unit optical element, the spacer 70 light control member 71 light transmitting unit, between the main portion 72 unit, filling unit 73 a transparent substrate

Claims (15)

A light guide optical sheet having a sheet-like first main body portion and a plurality of first unit optical elements that are arranged on the first main body portion and each extend in one direction;
A deflection optical sheet disposed at a position facing the light guide optical sheet, and is arranged on the sheet-like second main body portion and the second main body portion and protrudes toward the light guide optical sheet side A deflecting optical sheet having a second unit optical element;
A reflection sheet disposed at a position facing the light guide optical sheet from the side opposite to the deflection optical sheet;
An optical module comprising: a light source that irradiates a region between the light guide optical sheet and the reflective sheet with light traveling from one side to the other side in the one direction.   The thickness of the first main body portion along the normal direction to the sheet surface of the light guide optical sheet is larger than the width of the light emitting portion of the light source along the normal direction to the sheet surface of the light guide optical sheet. The optical sheet according to claim 1, which is thin.   3. The optical module according to claim 1, wherein the first unit optical element of the light guide optical sheet protrudes from the first main body toward the deflecting optical sheet.   3. The optical module according to claim 1, wherein the first unit optical element of the light guide optical sheet protrudes from the first main body toward the reflective sheet.   The optical module according to claim 1, wherein the deflection optical sheet is bonded to the light guide optical sheet.   The optical module according to claim 1, wherein the deflecting optical sheet is bonded to the light guide optical sheet through a top portion of the second unit optical element. The deflection optical sheet is bonded to the light guide optical sheet via a spacer provided on the second main body part or provided between the deflection optical sheet and the light guide optical sheet,
The optical module according to claim 1, wherein a top portion of the second unit optical element of the deflecting optical sheet is exposed to be separated from the light guide optical sheet.   8. The optical module according to claim 1, wherein each of the second unit optical elements extends in the other direction intersecting the one direction on the second main body portion. The light source has one or more light emitting units,
The optical module according to claim 1, wherein the light emitting unit is disposed such that an optical axis thereof is directed to a position on the light guide optical sheet. The light source has one or more light emitting units,
The optical module according to claim 1, wherein the light emitting unit is disposed such that an optical axis thereof is directed to a position on the reflection sheet.   The optical module according to claim 1, wherein the light guide optical sheet is made of a thermoplastic resin.   12. The light source according to claim 1, further comprising a second light source that irradiates a region between the light guide optical sheet and the reflective sheet with light traveling from the other side to the one side in the one direction. The optical module as described.   The optical module according to claim 1, further comprising a polarizer provided on a side of the deflecting optical sheet opposite to a side facing the light guide optical sheet.   A display apparatus provided with the optical module as described in any one of Claims 1-13.   The display device according to claim 14, wherein the deflection optical sheet forms a surface on the most incident side of the liquid crystal display panel.

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