Patent Publication Number: US-11022843-B2

Title: Liquid crystal display apparatus

Description:
CROSS-REFERENCE OF RELATED APPLICATIONS 
     This application is a U.S. Continuation of International Patent Application No. PCT/JP2019/012244, filed on Mar. 22, 2019, which in turn claims the benefit of Japanese Application No. 2018-086778, filed on Apr. 27, 2018, the entire disclosures of which Applications are incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present disclosure relates to a liquid crystal display apparatus. 
     2. Description of the Related Art 
     JP-A-2014-48322 discloses a liquid crystal display apparatus in which a flexible wiring substrate on which an LED is mounted is connected to an end portion of a TFT substrate. The flexible wiring substrate is folded back to a back surface of a mold, and the LED is disposed on a side surface of a light guiding plate of a backlight. The flexible wiring substrate is further folded back and extends on a surface of the TFT substrate, and is fixed to a liquid crystal display panel by a double-sided adhesive tape. The flexible wiring substrate is further sandwiched and fixed between a claw portion formed on a metal frame and the mold. 
     SUMMARY OF THE INVENTION 
     The present disclosure has been devised in view of the related-art circumstances described above, and an object thereof is to provide a liquid crystal display apparatus that secures strength of the liquid crystal display apparatus while achieving a thin structure in which a liquid crystal panel and a back-side frame can be close to each other. 
     The present disclosure provides a liquid crystal display apparatus including: a quadrangular liquid crystal panel having a reflection layer on a back surface opposite to a display surface of the liquid crystal panel; a light guiding plate formed in a quadrangular shape substantially the same as that of the liquid crystal panel, being laminated on the display surface, and configured t diffusely reflect light incident from one end surface of the light guiding plate and emit the light toward the display surface; a back-side frame formed in a quadrangular shape substantially the same as that of the liquid crystal panel, configured to sandwich the liquid crystal panel, and disposed in parallel with the liquid crystal panel on a side opposite to the light guiding plate, and in which bent side plate portions that restrict a position of the light guiding plate are respectively provided on a pair of side portions that sandwich one side portion of the back-side frame along the one end surface; and a light source holding plate includes a light source fixing plate which faces the one end surface and a fixing plate portion which is fixed to a surface of the back-side frame on a side opposite to the liquid crystal panel, in which a light source that causes light to be incident on the one end surface is mounted on the light source fixing plate, and the back-side frame fixing plate portion is formed so as to be bent perpendicularly to the light source fixing plate. 
     According to the present disclosure, in the liquid crystal display apparatus, the strength of the apparatus can be secured while achieving the thin structure in which the liquid crystal panel and the back-side frame can be close to each other. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of an external appearance of a liquid crystal display apparatus according to a first embodiment. 
         FIG. 2  is a cross-sectional view taken along a line I-I in  FIG. 1 . 
         FIG. 3  is a cross-sectional view taken along a line II-II in  FIG. 1 . 
         FIG. 4  is a rear view of the liquid crystal display apparatus shown in  FIG. 1 . 
         FIG. 5  is a perspective view of one end portion of an LED holding plate shown in  FIG. 4  in an extending direction. 
         FIG. 6  is an exploded perspective view of members laminated between a light guiding plate and the LED holding plate. 
         FIG. 7  is a plan view of a fitting structure including a convex portion and a notch. 
         FIG. 8  is an exploded perspective view of the fitting structure including the convex portion and the notch. 
         FIG. 9  is an exploded perspective view of a positioning portion between a bulging portion and the LED holding plate. 
         FIG. 10  is an enlarged plan view of main parts showing an example of positioning dimensions of LEDs and the light guiding plate. 
         FIG. 11  is an operation illustrative view when a convex portion is relatively close to one end surface. 
         FIG. 12  is an operation illustrative view when the convex portion is relatively far from one end surface. 
         FIG. 13  is an operation illustrative view of one end surface that changes due to thermal expansion. 
         FIG. 14  is an operation illustrative view when one end surface is close to the LEDs. 
         FIG. 15  is an exploded perspective view illustrating reinforcing one side portion of a back-side frame. 
         FIG. 16  is an exploded perspective view illustrating a structure in which a flexible wiring substrate connected to a liquid crystal panel is connected to a relay substrate across one side portion. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS 
     (Background to Contents of First Embodiment) 
     In a related transmissive liquid crystal display apparatus, a light guiding plate is disposed on a back side of a liquid crystal panel. Since a back-side frame that supports the liquid crystal panel and the light guiding plate is disposed on a side opposite to the liquid crystal panel with respect to the light guiding plate and sandwiches the light guiding plate together with the liquid crystal panel. Therefore, a bent portion corresponding to a thickness of the light guiding plate can be formed on each side portion of the back-side frame. On the contrary, in a reflective liquid crystal display apparatus that can provide high visibility even in an environment under sunlight, a light guiding plate is disposed on a display surface side of a liquid crystal panel. As a result, when it is attempted to reduce a thickness of the liquid crystal display apparatus, the back-side frame is disposed immediately on a side opposite to the light guiding plate with respect to the liquid crystal panel sandwiched between the back-side frame and the light guiding plate. Therefore, a bent portion that blocks lead-out of a flexible wiring substrate cannot be formed on one side portion of the back-side frame along an end surface of the liquid crystal panel from which the flexible wiring substrate is led out. In the back-side frame, the one side portion where no bent portion can be formed tends to bend toward front and back surface sides, and it may be difficult to secure strength of the liquid crystal display apparatus. 
     Hereinafter, a liquid crystal display apparatus that secures its strength will be described. 
     Hereinafter, an embodiment specifically disclosing a liquid crystal display apparatus according to the present disclosure will be described in detail with reference to the drawings as appropriate. However, an unnecessarily detailed description may be omitted. For example, a detailed description of a well-known matter or a repeated description of substantially the same configuration may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding of those skilled in the art. It is to be understood that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the range of the claims. 
     First Embodiment 
       FIG. 1  is a perspective view of an external appearance of a liquid crystal display apparatus  11  according to a first embodiment. The liquid crystal display apparatus  11  according to the first embodiment includes a liquid crystal panel  13 , a light guiding plate  15 , and a frame  17  as main components. 
     In the liquid crystal display apparatus  11 , a front light  19  is provided on a surface side of the reflective liquid crystal panel  13  as an auxiliary light source. The front light  19  is configured by the light guiding plate  15  and LEDs  21  that is a light source. The liquid crystal panel  13  does not emit light by itself, changes a transmission intensity of light so as to perform display, and can be driven with an effective voltage of, for example, several volts. The reflective liquid crystal panel  13  includes a reflection layer  23  on a lower side and performs display using reflected light from the reflection layer  23  of external light. Therefore, power consumption is extremely low. In the liquid crystal display apparatus  11 , the reflective liquid crystal panel  13  includes the front light  19 . Accordingly, high visibility under sunlight and visibility at night are made possible. Then, as compared with a transmissive liquid crystal panel including a backlight used in a related-art mobile phone or the like, a cooling fan can also be eliminated. Therefore, the power consumption can be significantly reduced. 
     In the first embodiment, the light source is not limited to the LED  21  and may be, for example, a cold cathode fluorescence lamp called a CCFL. 
       FIG. 2  is a cross-sectional view taken along a line I-I in  FIG. 1 . The liquid crystal panel  13  is configured by sandwiching a liquid crystal between a quadrangular upper glass on which a segment electrode group is formed and a quadrangular lower glass on which a common electrode group is formed. The liquid crystal is sealed in a gap between the upper glass and the lower glass and an outer periphery thereof is sealed. The segment electrode group and the common electrode group are connected to one end of, for example, an FFC  25  (flexible flat cable) or an FPC (flexible printed wiring board) in which a conductor is pattern-printed on a flexible insulation substrate. The other end of the FFC  25  or the like is connected, by a relay substrate  27 , to a driver or the like that drives the liquid crystal. 
     In the first embodiment, the liquid crystal panel  13  is formed to have a size of, for example, 32 inches. The size of the liquid crystal panel  13  is not limited thereto. 
     The relay substrate  27  supplies an electrical signal or electrical energy that drives the liquid crystal panel  13 . The liquid crystal panel  13  displays a desired image on a display surface  29  by the electrical signal or the electrical energy supplied from the relay substrate  27 . 
     The liquid crystal display apparatus  11  includes the reflection layer  23  disposed on a back surface opposite to the display surface  29 . The reflection layer  23  may be provided as a reflection plate on the lower glass, or may be attached as a reflection sheet to the lower glass. The reflection layer  23  reflects external light transmitted through the light guiding plate  15  and the liquid crystal panel  13  toward the liquid crystal panel  13 . Further, the reflection layer  23  reflects light emitted from the light guiding plate  15  and transmitted through the liquid crystal panel  13  toward the liquid crystal panel  13 . 
     The light guiding plate  15  is formed in a quadrangle substantially the same as that of the liquid crystal panel  13 . The shapes of the liquid crystal panel  13  and the light guiding plate  15  may not be formed in a quadrangular shape as long as a condition is satisfied under which the liquid crystal panel  13  and the light guiding plate  15  are positioned by the light guiding plate  15  and a back-side frame  37  in the vicinity of end portion sides of one side along one end surface  31 . In the first embodiment, the light guiding plate  15  is formed of a transparent plate material made of acrylic resin. The light guiding plate  15  is not limited to the acrylic resin, and may be, for example, glass. 
     The light guiding plate  15  is laminated on the display surface  29  of the liquid crystal panel  13 . The light guiding plate  15  diffusely reflects light incident from the one end surface  31  and emits the light toward the display surface  29  of the liquid crystal panel  13 . The light guiding plate  15  has, for example, a prism processing performed on a surface side and an anti-reflection material applied on a back surface side. The light incident from the one end surface  31  of the light guiding plate  15  propagates through the light guiding plate  15  as a medium, and a part thereof is reflected by a prism-processed portion on the surface side and emitted as diffused light toward a liquid crystal panel side. Accordingly, the light guiding plate  15  has a function of reflecting light from the LEDs  21  and causing the light to be incident on the liquid crystal panel  13 , a function of transmitting light reflected by the reflection layer  23  to an outside, and a function of transmitting light from the outside to the liquid crystal panel  13 . 
     The light guiding plate  15  is adhered to the display surface  29  of the liquid crystal panel  13  by an adhesive layer  57  to be described later. A peripheral edge of the light guiding plate  15  integrated with the liquid crystal panel  13  is held on the frame  17  by a frame member  33  (so-called bezel). The frame member  33  is fixed (screwed) to the frame  17  by a screw that is a fastener. A bezel upper side  35  is screwed to the back-side frame  37  that constitutes the frame  17 . A bezel lower side  39  is screwed to an LED holding plate  41  that constitutes the frame  17 . 
       FIG. 3  is a cross-sectional view taken along a line II-II in  FIG. 1 . Bezel lateral sides  43  are respectively screwed to bent side plate portions  45  of the back-side frame  37 . 
     The light guiding plate  15  includes a pair of convex portions  49  (see  FIG. 8  for details) that protrude outward from a pair of parallel adjacent end surfaces  47  (see  FIG. 7  for an example of the end surfaces) that sandwich the one end surface  31 . As will be described later, one of the pair of convex portion  49  is fitted into a notch  51  provided in the back-side frame  37 . 
       FIG. 4  is a rear view of the liquid crystal display apparatus  11  shown in  FIG. 1 . In the first embodiment, in the frame  17 , the back-side frame  37  and the LED holding plate  41  that are separately formed are integrally fixed by screws  53  as fasteners. The back-side frame  37  is formed in a quadrangular shape substantially the same as that of the liquid crystal panel  13 . The LED holding plate  41  is formed in a long shape that extends along the one end surface  31 . 
     In the frame  17 , the back-side frame  37  and the LED holding plate  41  may be integrally formed by a single metal plate. 
       FIG. 5  is a perspective view of one end portion in the extending direction of the LED holding plate  41  shown in  FIG. 4 . The LED holding plate  41  includes an LED fixing plate  55  that is bent perpendicularly to the back-side frame  37  and faces the one end surface  31  of the light guiding plate  15 . In other words, the LED holding plate  41  and the LED fixing plate  55  are formed by bending one plate material perpendicularly to the back-side frame  37 , so that a plate material portion parallel to the back-side frame  37  and a plate material portion perpendicular to the back-side frame  37  (that is, the LED fixing plate  55 ) are formed. In the LED holding plate  41 , a plate material portion parallel to the back-side frame  37  serves as a back-side frame fixing plate portion  58 . On the LED fixing plate  55  of the LED holding plate  41 , a plurality of LEDs  21  that cause light to be incident on the one end surface  31  of the light guiding plate  15  are linearly arranged at equal intervals (see  FIGS. 2 and 7 ). 
       FIG. 6  is an exploded perspective view of members laminated between the light guiding plate  15  and the LED holding plate  41 . In the liquid crystal display apparatus  11 , the light guiding plate  15  is closely fixed to the display surface  29  of the liquid crystal panel  13  via the adhesive layer  57 . In the liquid crystal display apparatus  11 , the back-side frame  37 , the liquid crystal panel  13 , the adhesive layer  57 , and the light guiding plate  15  are sequentially laminated from a lower layer side of the liquid crystal display apparatus  11 . Among them, the liquid crystal panel  13  and the light guiding plate  15  are integrally assembled by the adhesive layer  57 . The light guiding plate  15  to which the liquid crystal panel  13  is integrally fixed is positioned on the back-side frame  37 . The frame member  33  is screwed to the back-side frame  37  and the LED holding plate  41 , so that the light guiding plate  15  positioned on the back-side frame  37  is held by the frame member  33  and the frame  17 . 
     In the first embodiment, the liquid crystal display apparatus  11  is assembled with the back-side frame  37  and the liquid crystal panel  13  not being fixed. 
     In the liquid crystal display apparatus  11 , the LED holding plate  41  is formed of a metal plate thicker than a plate thickness of the back-side frame  37 . 
     In the liquid crystal display apparatus  11 , a Z-bent portion  59  (see  FIG. 2 ) is formed on a side opposite to the LED fixing plate  55  of the LED holding plate  41 . The LED holding plate  41  has a component housing space  61  formed between the back-side frame  37  and the LED holding plate  41  (see  FIG. 2 ) by abutting a tip end of the Z-bent portion  59  against the back-side frame  37 . 
       FIG. 7  is a plan view of a fitting structure including a convex portion  49  and a notch  51 . In the light guiding plate  15  integrated with the liquid crystal panel  13 , the convex portions  49  that protrude from both sides along the extending direction of the one end surface  31  are fitted into the notches  51  of the back-side frame  37 . With this fitting structure, movement of the light guiding plate  15  in a surface direction is restricted, and the light guiding plate  15  is positioned on the back-side frame  37 . The liquid crystal panel  13  adhered to and integrated with the light guiding plate  15  is also similarly positioned on the back-side frame  37  via the light guiding plate  15 . 
       FIG. 8  is an exploded perspective view of the fitting structure including the convex portion  49  and the notch  51 . In the back-side frame  37 , the bent side plate portions  45  that face a pair of adjacent end surfaces  47  of the light guiding plate  15  are formed on a pair of adjacent side portions that sandwich the LED fixing plate  55 , respectively. Then, the pair of bent side plate portions  45  are provided with the notches  51  into which the convex portions  49  of the light guiding plate  15  are fitted. The convex portions  49  of the light guiding plate  15  are formed in the vicinity of the one end surface  31  on the pair of parallel adjacent end surfaces  47  that sandwich the one end surface  31 . Therefore, the notches  51  into which the convex portions  49  are fitted are also formed in the vicinity of the one end surface  31  in the pair of bent side plate portions  45 . Each of the convex portions  49  is formed with a protrusion length of, for example, about 2 mm. A frame-member-fixing bulging portion  63  for fixing the frame member  33  is formed on a bent side plate portion  45  on a light source fixing plate side of the LED holding plate  41  with respect to a notch  51 . 
       FIG. 9  is an exploded perspective view of a positioning portion  67  between a bulging portion  65  and the LED holding plate  41 . A pair of positioning portions  67  each including a positioning hole  69  and a fastener insertion hole  71  are formed in the LED holding plate  41 . The pair of positioning portions  67  are provided separately in a direction along the one end surface  31 . 
     On the other hand, a pair of bulging portions  65  that protrude toward the LED holding plate  41  are formed on the back-side frame  37 . The bulging portions  65  are also provided separately in the direction along the one end surface  31 . Each of the bulging portions  65  includes a boss  75  fitted into a positioning hole  69  of the back-side frame  37  and a female screw portion  77  with which a screw  53  is screwed, on a tip end seating surface  73  that is a flat surface. 
     In the back-side frame  37 , a side sandwiched between the pair of bent side plate portions  45  is one side portion  78 . In other words, in the back-side frame  37 , the bent side plate portions  45  that restrict a position of the light guiding plate  15  are respectively formed on a pair of side portions that sandwich the one side portion  78  along the one end surface  31 . FFCs  25  connect the liquid crystal panel  13  to the relay substrate  27  arranged on front and back surfaces of the back-side frame  37  so as to straddle the one side portion  78 . The back-side frame  37  does not form a bent portion on the one side portion  78 , so that the FFCs  25  that connect the liquid crystal panel  13  disposed on a front surface side of the back-side frame  37  to the relay substrate  27  do not interfere with the bent portion. As a result, a thin structure in which the back-side frame  37  and the liquid crystal panel  13  can be close to each other is achieved. 
     Next, a positional relationship between the LEDs  21  and the light guiding plate  15  will be described using specific numerical values as an example. 
       FIG. 10  is an enlarged plan view of main parts showing an example of positioning dimensions of the LEDs  21  and the light guiding plate  15 . In a positioning structure of the light guiding plate  15  and the LEDs  21 , a gap between the one end surface  31  of the light guiding plate  15  and a light emitting surface of the LEDs  21  can be set to, for example, about 0.5 mm. In this case, a distance from the one end surface  31  to a convex portion  49  is set in the vicinity of, for example, about 50 mm. 
       FIG. 11  is an operation illustrative view when the convex portion  49  is relatively close to the one end surface  31 . Here, if the distance from the one end surface  31  to the convex portion  49  is 55 mm, a gap A when a temperature changes from 20° C. to 60° C. at a room temperature is 0.4 mm (an amount of change: 0.1 mm). 
       FIG. 12  is an operation illustrative view when the convex portion  49  is relatively far from the one end surface  31 . A comparative example in which a position of the convex portion  49  is not in the vicinity of the one end surface  31  will be described. 
     In a light guiding plate  79  of the comparative example, the convex portion  49  is formed at a position of, for example, 269 mm from the one end surface  31 . In the light guiding plate  79  according to the comparative example, when a temperature changes from 20° C. to 60° C. at a room temperature, the amount of change of the gap A becomes 0.5 mm or more. Therefore, the one end surface  31  of the light guiding plate  79  is in contact with the LEDs  21 . 
     An amount of change due to a temperature change in the light guiding plate  15  shown in  FIG. 11  and the light guiding plate  79  shown in  FIG. 12  will be described. 
       FIG. 13  is an operation illustrative view of the one end surface  31  that changes due to thermal expansion. In the figure, L is a distance from the one end surface  31  to the convex portion  49 , A is a gap between the LED light emitting surface and the one end surface  31 , and B is a dimensional change amount of an L value. 
     [Coefficient] 
     A linear expansion coefficient of the light guiding plate  15  (acrylic resin material) is 7×10 −5 /° C. 
     A linear expansion coefficient of the back-side frame  37  (aluminum material) is 2.35×10 −5 /° C. 
     [Calculation Formula 1] 
     An amount of change B of an L dimension when a temperature rises from 20° C. to 60° C. at a room temperature
 
 B=L ×(7−2.35)10 −5 ×(60−20)
 
     [Calculation Formula 2] 
     The gap A between the LED light emitting surface and the one end surface  31  (a gap dimension at a room temperature is 0.5 mm)
 
 A= 0.5− B  
 
     [Calculation Example] 
     When L=55
 
 B= 55×(7−2.35)10 −5 ×(60−20)=0.1023 mm
 
 A= 0.5−0.1023≈0.4 mm
 
     When L=269
 
 B= 269×(7−2.35)10 −5 ×(60−20)=0.500 mm
 
 A= 0.5−0.5=0
 
       FIG. 14  is an operation illustrative view when the one end surface  31  is close to the LEDs  21 . Further, when the one end surface  31  of the light guiding plate  15  is close to the LEDs  21 , a light non-incident region  81  where light from the LEDs  21  is not incident is generated. In this case, the light guiding plate  15  tends to cause unevenness in color and brightness on a surface facing the liquid crystal panel that emits light toward the liquid crystal panel  13 . 
     Next, an operation of the liquid crystal display apparatus  11  according to the above-described first embodiment will be described. 
     The liquid crystal display apparatus  11  according to the first embodiment includes the quadrangular liquid crystal panel  13  having the reflection layer  23  on the back surface opposite to the display surface  29 . The liquid crystal display apparatus  11  includes the light guiding plate  15  that is formed in the quadrangular shape substantially the same as that of the liquid crystal panel  13  and is laminated on the display surface  29 , diffusely reflects light incident from the one end surface  31  and emits the light toward the display surface  29 , and includes the pair of convex portions  49  that protrude outward from a vicinity of the one end surface  31  on the pair of parallel adjacent end surfaces  47  that sandwich the one end surface  31 . The liquid crystal display apparatus  11  includes the frame  17  that has the LED holding plate  41  (an example of a light source holding plate) in which the plurality of LEDs  21  (an example of a light source) are mounted on the LED fixing plate  55 , the plurality of LEDs  21  causing light to be incident on the one end surface  31 , the LED fixing plate  55  being bent perpendicularly to the back-side frame  37  (an example of a back-side portion) and facing the one end surface  31 , the back-side frame  37  being formed in the quadrangular shape substantially the same as that of the liquid crystal panel  13 , in which the bent side plate portions  45  that face the pair of adjacent end surfaces  47  are respectively formed on the pair of adjacent side portions of the back-side frame  37  that sandwich the LED fixing plate  55 , and in which the notches  51  into which the convex portions  49  are fitted are provided in the pair of bent side plate portions  45 . 
     That is, in the light guiding plate  15  of the liquid crystal display apparatus  11 , the convex portions  49  that protrude outward from the pair of adjacent end surfaces  47  are fitted into the notches  51  formed in the pair of bent side plate portions  45  of the back-side frame  37 . The light guiding plate  15  and the frame  17  on which the LEDs  21  are mounted are positioned by a relative movement in a surface direction being restricted by the fitting of the convex portions  49  and the notches  51 . The liquid crystal panel  13  is fixedly disposed on the light guiding plate  15 . Accordingly, the light guiding plate  15  and the liquid crystal panel  13  can be positioned with simple components as compared with a related-art structure in which a plurality of frame-shaped members are used by stacking the frame-shaped members inside and outside. 
     Therefore, in the liquid crystal display apparatus  11  according to the first embodiment, positional deviation between the light source and the light guiding plate  15  for the front light can be prevented while achieving edge narrowing with simple components. 
     In the light guiding plate  15  and the back-side frame  37 , the convex portions  49  provided on the light guiding plate  15  are respectively fitted into the notches  51  provided in the back-side frame  37 . As a fitting structure, conversely, a fitting structure is also conceivable in which the convex portions  49  provided on the back-side frame  37  are respectively fitted into the notches  51  provided in the light guiding plate  15 . In this case, since the notches  51  are provided in the light guiding plate  15 , a defect occurs in waveguide of light. In order to obtain the same amount of light, the light guiding plate  15  has to be formed largely by that amount. On the contrary, in the configuration in which the convex portions  49  are provided on the light guiding plate  15 , an outer shape of the light guiding plate  15  excluding the convex portions  49  can be made smaller than a case where the notches are provided, while obtaining the same amount of light. Accordingly, the light guiding plate  15  provided with the convex portions  49  can be made smaller, lighter, and reduced in a material cost as compared with the light guiding plate  15  provided with the notches. 
     Since the frame member  33 , that holds a periphery of the light guiding plate  15  and the liquid crystal panel  13 , does not have a positioning structure and positioning strength, the liquid crystal display apparatus  11  can be formed to be thin and have a narrow edge. 
     Further, the frame  17  includes the LED fixing plate  55  that is bent perpendicularly to the back-side frame  37  and faces the one end surface  31  of the light guiding plate  15 . The LED fixing plate  55  is provided with the plurality of LEDs  21  along the one end surface  31  of the light guiding plate  15 . The convex portions  49  and the notches  51  that position the light guiding plate  15  and the frame  17  are arranged in the vicinity of the one end surface  31  of the light guiding plate  15 . The one end surface  31  of the light guiding plate  15  approaches (displaces) the LEDs  21  when the one end surface  31  is thermally expanded by driving of the LEDs  21  or the like. At this time, since a vicinity of the one end surface  31  of the light guiding plate  15  is fitted into and fixed to the notches  51  of the frame  17 , an expansion amount between the one end surface  31  and the LEDs  21  is suppressed to be small. 
     An amount of change between the one end surface  31  and the LEDs  21  increases as a distance between the one end surface  31  and a convex portion  49  increases. In the liquid crystal display apparatus  11 , since the convex portion  49  is disposed in the vicinity of the one end surface  31 , the amount of change between the one end surface  31  and the LEDs  21  due to thermal expansion of the light guiding plate  15  is small. That is, in the liquid crystal display apparatus  11 , it is possible to prevent positional deviation of both movement of the entire light guiding plate in the surface direction and displacement of the one end surface  31  with respect to the LEDs  21  due to the thermal expansion of the light guiding plate  15 . 
     The liquid crystal display apparatus  11  according to the first embodiment includes the quadrangular liquid crystal panel  13  having the reflection layer  23  on the back surface opposite to the display surface  29 . The liquid crystal display apparatus  11  includes the light guiding plate  15  that is formed in the quadrangular shape substantially the same as that of the liquid crystal panel  13  and is laminated on the display surface  29 , and diffusely reflects the light incident from the one end surface  31  and emits the light toward the display surface  29 . The liquid crystal display apparatus  11  includes the back-side frame  37  that is formed in the quadrangular shape substantially the same as that of the liquid crystal panel  13  and sandwiches the liquid crystal panel  13 , that is disposed in parallel with the liquid crystal panel  13  on the side opposite to the light guiding plate  15 , and in which the bent side plate portions  45  that restrict the position of the light guiding plate  15  are respectively formed on the pair of side portions that sandwich the one side portion  78  along the one end surface  31 . The liquid crystal display apparatus  11  includes the LED holding plate  41  that is formed separately from the back-side frame  37 , in which the LEDs  21  that cause light to be incident on the one end surface  31  are mounted on the LED fixing plate  55  that faces the one end surface  31 , and in which the back-side frame fixing plate portion  58  formed by being bent perpendicularly to the LED fixing plate  55  is fixed to the surface of the back-side frame  37  on the side opposite to the liquid crystal panel  13 . 
       FIG. 15  is an exploded perspective view illustrating reinforcing the one side portion  78  of the back-side frame  37 . In the liquid crystal display apparatus  11 , the frame  17  includes two members: the back-side frame  37  and the LED holding plate  41  (see  FIG. 2 ). Since the back-side frame  37  and the LED holding plate  41  are separate bodies, the LED holding plate  41  can be integrally fixed to the back-side frame  37  along the one side portion  78 . The LED holding plate  41  is formed in an L-shape in which the back-side frame fixing plate portion  58  is perpendicularly bent with respect to the LED fixing plate  55 . As a result, in the back-side frame  37 , the one side portion  78  where a bent portion cannot be formed is reinforced by the L-shaped integrally fixed LED holding plate  41 . The back-side frame  37  to which the LED holding plate  41  is fixed is restricted from bending toward front and back surface sides while achieving a reduction in thickness without blocking lead-out of the FFCs  25  from the laminated liquid crystal panel  13 . That is, the liquid crystal display apparatus  11  can secure strength of an apparatus while achieving the reduction in thickness. 
     In the frame  17 , the back-side frame  37  and the LED holding plate  41 , which are separately formed, are integrally fixed by the screws  53  (an example of a fastener). 
     In the liquid crystal display apparatus  11 , the frame  17  includes two members: the back-side frame  37  and the LED holding plate  41 . Since the back-side frame  37  and the LED holding plate  41  are separate bodies, workability of assembling the liquid crystal panel  13  and the light guiding plate  15  to the frame  17  is satisfactorily achieved as compared with a case where the frame  17  is integrated. That is, after the back-side frame  37 , the liquid crystal panel  13  and the light guiding plate  15  are positioned and assembled, the LED holding plate  41  can be fixed to the back-side frame  37  by covering the relay substrate  27  and the like provided on the back-side frame  37 . 
     The back-side frame  37  and the LED holding plate  41  are formed as separate bodies, so that the back-side frame  37  and the LED holding plate  41  can be formed of metal plates having different thicknesses. 
     The pair of positioning portions  67  each including the positioning hole  69  and the fastener insertion hole  71  are provided on the LED holding plate  41  so as to be separate from each other in a direction along the one end surface  31 . The back-side frame  37  is provided with the pair of bulging portions  65  each including the boss  75  fitted into the positioning hole  69  and the female screw portion  77  with which a fastener is screwed on the tip end seating surface  73  that protrudes toward the LED holding plate  41  and has a flat surface. 
     In the liquid crystal display apparatus  11 , the bulging portions  65  that protrude toward the LED holding plate  41  are provided on the back surface of the back-side frame  37 . The boss  75  and the female screw portion  77  are formed on the tip end seating surface  73  of the bulging portion  65 . The pair of bosses  75  are separately provided in the direction along the one end surface  31 . Accordingly, the light guiding plate  15  can effectively prevent positional deviation in which the one end surface  31  that faces the LEDs  21  rotates about a rotation axis perpendicular to the light guiding plate  15  at a fixed position. 
     Since the boss  75  provided on the tip end seating surface  73  of the bulging portion  65  can be fitted into the positioning hole  69  of the LED holding plate  41  with high accuracy, positioning accuracy can be improved as compared with a positioning and fixing structure using only a fastener. 
     The bulging portion  65  can be formed on the back-side frame  37  by drawing. Therefore, it is possible to secure a screwing space at a tip end of a fastener and prevent the tip end of the fastener from interfering with the liquid crystal panel  13  without using a separate member. Further, between the back-side frame  37  and the LED holding plate  41 , a gap that can house a component corresponding to a protruding height of the bulging portions  65  can be easily formed. 
     The light guiding plate  15  is closely fixed to the display surface  29  of the liquid crystal panel  13  via the adhesive layer  57 . 
     In the liquid crystal display apparatus  11 , the light guiding plate  15  and the liquid crystal panel  13  are closely fixed via the adhesive layer  57 , so that an integrated structure having higher strength than that in a case where each of the light guiding plate  15  and the liquid crystal panel  13  is a single item can be formed. Further, the light guiding plate  15  can be brought into close contact with the display surface  29  of the liquid crystal panel  13  evenly by the adhesive layer  57 , and an air gap can be prevented from being formed between the liquid crystal panel  13  and the light guiding plate  15 . Accordingly, by using the adhesive layer  57  having a particularly low refractive index (a layer made of silicon or the like), double reflection can be prevented. 
     In the liquid crystal display apparatus  11 , the back-side frame  37  and the liquid crystal panel  13  are not fixed to each other. 
     In the liquid crystal display apparatus  11 , when the back-side frame  37  and the liquid crystal panel  13  are temporarily fixed and the liquid crystal panel  13  and the light guiding plate are thermally expanded, a reaction force received from the back-side frame  37  can be prevented from being applied to the fitting structure of the convex portions  49  and the notches  51 . Accordingly, positional deviation between the one end surface  31  of the light guiding plate  15  and the LEDs  21  due to an excessive stress being applied to the fitting structure of the convex portions  49  and the notches  51  can be prevented. 
     In the liquid crystal display apparatus  11 , the LED holding plate  41  is formed of a metal plate thicker than a plate thickness of the back-side frame  37 . 
     In the liquid crystal display apparatus  11 , only the LED holding plate  41  that supports an entire load of the liquid crystal display apparatus  11  can be made of a small and thick plate material, and the back-side frame  37  that mainly holds the light guiding plate  15  and the liquid crystal panel  13  can be made of a plate material thinner than the LED holding plate  41 . Accordingly, a thickness of the back-side frame  37  can be reduced as compared with a case where the back-side frame  37  and the LED holding plate  41  are configured to have the same plate thickness, so that a weight of the apparatus can be reduced. 
     Further, by making the LED holding plate  41  thick, a thermal capacity can be increased as compared with a thin plate material. Accordingly, heat dissipation performance of the LEDs  21  can be improved by improving thermal conduction from the LEDs  21 . As a result, a life of the LEDs  21  can be extended. 
     In the liquid crystal display apparatus  11 , the relay substrate  27  is fixed to the surface on the side opposite to the liquid crystal panel  13  of the back-side frame  37 , and the other end of each FFC  25  having one end connected to the liquid crystal panel  13  is connected to the relay substrate  27  across the one side portion  78  of the back-side frame  37 . 
       FIG. 16  is an exploded perspective view illustrating a structure in which an FFC  25  connected to the liquid crystal panel  13  is connected to the relay substrate  27  across the one side portion  78 . In the liquid crystal display apparatus  11 , the liquid crystal panel  13  and the relay substrate  27  are arranged on front and back sides of the back-side frame  37 . The FFC that connects the liquid crystal panel  13  to the relay substrate  27  is wired across the one side portion  78  of the back-side frame  37 . Accordingly, the liquid crystal panel  13  and the relay substrate  27  can be easily connected to each other without forming a notch or a through hole in the back-side frame  37 . Further, since no notch or through hole is formed in the back-side frame  37 , a decrease in strength of the back-side frame  37  can be prevented. 
     In the liquid crystal display apparatus  11 , the component housing space  61  is provided between the back-side frame  37  and the LED holding plate  41 . 
     In the liquid crystal display apparatus  11 , the Z-bent portion  59  is formed on an end edge of the back-side frame fixing plate portion  58  on a side opposite to the LED fixing plate  55 , and the Z-bent portion  59  abuts against the back-side frame  37 , so that the component housing space  61  that houses the relay substrate  27  is formed between the back-side frame  37  and the back-side frame fixing plate portion  58 . 
     In the liquid crystal display apparatus  11 , the Z-bent portion  59  formed on the end edge of the back-side frame fixing plate portion  58  abuts against the back-side frame  37 , so that the back-side frame fixing plate portion  58  floats above the back-side frame  37  and is fixed. A gap formed by the back-side frame fixing plate portion  58  floating above the back-side frame  37  is the component housing space  61 . In the liquid crystal display apparatus  11 , it is possible to secure a thin and wide space over an entire area of an overlapping portion by only securing a relatively small gap in the overlapping portion between the back-side frame  37  and the LED holding plate  41 . Accordingly, the overlapping portion between the back-side frame  37  and the LED holding plate  41  is effectively used, and it is possible to easily secure a space for housing a thin and relatively large-sized component such as a substrate while avoiding interference with other components. 
     In the liquid crystal display apparatus  11 , the relay substrate  27  is fixed close to the one side portion  78 , and the Z-bent portion  59  is formed close to the relay substrate  27 . 
     In the liquid crystal display apparatus  11 , it is possible to prevent an increase in a connection length of the FFC  25  led out from the liquid crystal panel  13  and connected to the relay substrate  27 . Further, the component housing space  61  can be made compact. 
     In the liquid crystal display apparatus  11 , the LED holding plate  41  is formed of a metal material having a higher thermal conductivity than that of the back-side frame  37 . 
     In the liquid crystal display apparatus  11 , heat from the LEDs  21  fixed to the LED fixing plate  55  is satisfactorily transferred from the LED fixing plate  55  to the back-side frame fixing plate portion  58 . That is, the LED holding plate  41  has a small thermal gradient (temperature difference) on an entire surface, and an efficient heat dissipation effect can be obtained even at an end portion. As a result, a cooling effect of the LEDs  21  can be enhanced, and the life of the LEDs  21  can be extended. 
     As described above, according to the liquid crystal display apparatus  11  having the above-described configuration, since the back-side frame  37  and the LED holding plate  41  are separately fixed, a reduction in thickness, heat dissipation performance, and a protective structure of the FFCs  25  can be simultaneously achieved while increasing strength of an apparatus. Particularly, the liquid crystal display apparatus  11  can secure the protective structure of the FFCs  25  when handled as a unit in an intermediate stage of a finished product. 
     Although the various embodiments are described above with reference to the drawings, it is needless to say that the present disclosure is not limited to such examples. It will be apparent to those skilled in the art that various alterations, modifications, substitutions, additions, deletions, and equivalents can be conceived within the scope of the claims, and it should be naturally understood that they also belong to the technical scope of the present disclosure. Components in the various embodiments described above may be combined optionally in the range without deviating from the spirit of the invention. 
     This application is a continuation of PCT application No. PCT/JP2019/012244, which was filed on Mar. 22, 2019 based on Japanese Patent Application (No. 2018-086778) filed on Apr. 27, 2018, the contents of which are incorporated herein by reference. 
     The present disclosure is useful as a liquid crystal display apparatus that secures strength of an apparatus while achieving a thin structure in which a liquid crystal panel and a back-side frame can be close to each other.