JP2010190918A - Light reflector and surface light source device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely prevent an opposite member from being damaged, by forming a plurality of projections on the surface of a light reflector, so that the light reflector is prevented from adhering to a light guiding body being the opposite member, by using no beads for forming the plurality of projections, so that risk of the beads falling off is eliminated, and further by making hardness of the plurality of projections be properly adjusted. <P>SOLUTION: There are provided a light reflector 2 having a film 5 stuck on a base material 4 with an adhesive layer 6 and a surface light source device 1 using this light reflector. The film 5 includes a plurality of projected parts 7 having a space inside. While the film 5 is stuck on the base material 4, a plurality of projected parts 7 and thereby, a plurality of projections 9 are formed between the base material 4 and the film 5, wherein an air layer A is formed inside these projections 9. Since the inside of the projections 9 is the air layer A, the hardness of the projections 9 is adjusted, and the light guiding body 3 is prevented from being damaged by the light reflector 2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a light reflector that reflects light. The present invention also relates to a planar light source device that emits light in a planar shape.

  For example, a surface light source device that is a light emission source is attached to an electronic device such as a light-transmissive liquid crystal display device that is not self-luminous. When this planar light source device is provided on the back surface (that is, the surface opposite to the display surface) of the liquid crystal cell that is a component of the liquid crystal display device, the planar light source device may be called a backlight.

  As a conventional planar light source device, a light source that emits light, a light guide that receives light from the light source from one surface and emits it from a light exit surface that is the other surface, and the light emission of the light guide 2. Description of the Related Art A planar light source device having a light reflector provided to face a surface opposite to a surface is known. The light reflector used here emits light from the light source and enters the inside of the light guide, and further reflects the light that is about to exit from the back of the light guide to the outside and guides it back to the inside of the light guide. . Thereby, the emission efficiency of the light emitted from the light emitting surface of the light guide can be increased.

  As conventional light reflectors, there are known light reflectors having a structure in which protrusions, protrusions, convex portions, etc. are formed on the surface of a substrate by particles, beads, etc. (for example, Patent Document 1, Patent Document 2 and (See Patent Document 3). These protrusions, protrusions, and convex portions prevent the mating member (for example, the light guide) that the light reflector contacts from being damaged by the light reflector, or the light reflector partially adheres to the mating member. This is used to prevent the occurrence of luminance white spots, luminance unevenness and the like.

  Conventionally, a technique for forming a plurality of recesses on the surface of a reflective film (corresponding to the light reflector of the present invention) by embossing is known (see, for example, Patent Document 4). A plurality of convex portions are inevitably formed next to the plurality of concave portions. These plurality of concavo-convex portions are mainly used for preventing the Newton ring from being generated by preventing the reflection film and the light guide plate (that is, the mating member) from coming into close contact with each other, and appropriately diffusing light. It has been.

  Furthermore, conventionally, another technique is known in which a plurality of recesses are formed on the surface of a foam sheet (corresponding to the light reflector of the present invention) (see Patent Document 5). A plurality of convex portions are inevitably formed next to the plurality of concave portions. In this technology, by forming a plurality of irregularities on the surface of the foam sheet, which is a light reflector, the brightness of light emitted from the foam sheet is prevented from being unevenly distributed in a limited direction, and uniform from the foam sheet. The light can be emitted.

Japanese Patent Laying-Open No. 2003-001737 (pages 2 and 3, FIG. 1) Japanese Unexamined Patent Publication No. 2003-084110 (Page 4, FIGS. 1 and 2) Japanese Patent Laid-Open No. 2003-092018 (pages 3 to 4, FIG. 1) JP 2001-266629 A (pages 2 and 3, FIGS. 1 and 2) JP 2003-270415 A (3rd, 5th page, FIG. 2)

  In the above conventional light reflector provided with particles, beads, etc. on the surface, the particles, beads, etc. fall off from predetermined locations on the base material, which is a component of the light reflector, due to shock and vibration in the assembly process and transport process. Thus, the other member (for example, the light guide) facing the light reflector may be damaged.

  When such scratches are attached, there is a risk that point defects such as white spots and bright spots may occur when the light source attached to the counterpart member is turned on. In addition, when an electronic device configured using a light reflector or a planar light source device, such as a liquid crystal display device, is pressed from the front and back, the light reflector itself or the counterpart member is damaged, causing point defects or uneven brightness. Could occur.

  Moreover, in the conventional light reflector which formed the recessed part and the convex part on the surface of the reflective film which is a light reflector, generally, a reflective film is a white film and this white film uses a base substrate with a pigment. It is produced by coloring. In this conventional configuration, since the pigment component used for coloring is exposed on the surface layer, the hardness of the concave portion and the convex portion is relatively high, so that the mating member (for example, the light guide) that contacts these is scratched. There was a problem that it was easy. In addition, since the elastic restoring force of the concave and convex portions is weak, when the reflective film, which is a light reflector, is partially pressed and deformed, it cannot be restored to its original shape. There was also a problem that occurred.

The present invention has been made in view of the above problems,
(1) By forming a plurality of protrusions on the surface of the light reflector, the light reflector can be prevented from coming into close contact with the mating member, thereby preventing occurrence of uneven brightness, etc.
(2) By stopping the use of particles, beads, etc. to form the plurality of protrusions, it is possible to fundamentally prevent the occurrence of a situation in which particles fall off from a predetermined position and damage the counterpart member. (3) By appropriately adjusting the hardness or rigidity of the plurality of protrusions provided on the surface of the light reflector, it is possible to reliably prevent the counterpart member from being damaged,
It is an object to provide a light reflector and a planar light source device that can achieve the above.

  The light reflector according to the present invention has a base material and a film adhered to the base material by an adhesive layer or an adhesive layer, and the film has a plurality of convex portions and / or concave portions having spaces therein. A plurality of protrusions are formed by the protrusions and / or the recesses between the substrate and the film in a state where the film is adhered to the substrate. The inside of the protruding portion is characterized in that an air layer is formed.

According to the light reflector having this configuration, since the plurality of projecting portions are provided on the base material, the light reflector can be prevented from coming into close contact with the counterpart member. Therefore, when the counterpart member is a light guide, it is possible to prevent uneven brightness from occurring in the light emitted from the light guide.
In addition, a plurality of protrusions are formed on the base material by the protrusions and / or recesses formed on the film laminated on the base material, and the protrusions are formed by particles, beads, etc. Therefore, the situation where the mating member is damaged by dropping off the beads or the like does not occur in the first place.

  In addition, since an air layer is formed inside the plurality of projecting portions protruding on the base material, when the projecting portion is solid (the inside is not filled with space but is filled with material) In comparison, it is possible to appropriately adjust the individual hardness or rigidity of the plurality of projecting portions, and therefore it is possible to reliably prevent the mating member such as the light guide that contacts the projecting portions from being damaged.

  Furthermore, since the convex part and / or concave part are formed in the film laminated | stacked on a base material, many air chambers are formed between a light reflection body and the other party member (for example, light guide body) facing it. The Therefore, when an electronic device (for example, a liquid crystal display device) including the light reflector and the counterpart member receives pressure from the front and back, the pressure can be dispersed in the light reflector. For this reason, compared with the conventional apparatus which did not interpose an air chamber, it became easy to maintain the initial characteristic of an electronic device.

  In addition, adhesion is sticking with an adhesive, and an adhesive is a material having viscosity in a steady state and having a soft state. On the other hand, adhesion is sticking with an adhesive, and adhesive is a material that is hard in a steady state and exhibits viscosity or fluidity when heated.

  The film may be formed to have only a plurality of convex portions, may be formed to have only a plurality of concave portions, or may be formed to have both convex portions and concave portions. . In addition, a convex part is a part which made the film protrude upwards with a convex lower metal mold | die, and is a part which protrudes in the direction away from the base material, when a film is affixed on a base material. . On the other hand, a recessed part is a part which protruded the film below with the convex upper metal mold | die, and is a part which protrudes in the direction which goes to a base material, when a film is affixed on a base material.

  When only the convex part is formed on the film, the convex part is formed by the convex part 7 itself as indicated by reference numeral 9 in FIG. On the other hand, when only the concave portion is formed on the film, the projecting portion is formed around the outer side of the concave portion 11 as indicated by reference numeral 9 in FIG. On the other hand, when both the convex part and the concave part are formed on the film, the protruding part is formed around the outside of the concave part 11 and inside the convex part 7 as indicated by reference numeral 9 in FIG.

  In the light reflector according to the present invention, it is desirable that the convex portions and / or the concave portions are provided in a dot shape, that is, in an island shape with a space therebetween in a plan view. With this configuration, when the light reflector is brought into surface contact with another member (for example, the light guide of the planar light source device), the contact positions of the two can be made into a plurality of minute regions that are appropriately distributed.

  The convex portion and / or the concave portion can be provided so as to form a plurality of rows in each of two orthogonal directions, for example, in the vertical direction and the horizontal direction, that is, in a so-called lattice shape. Alternatively, they can be arranged in other regular plane patterns. Furthermore, they may be arranged in a random (disordered) plane pattern.

  The convex portion and / or the concave portion can be created by an arbitrary method, but is preferably formed by embossing using a pressing die. Embossing is a general term for techniques for forming a projecting pattern, but the embossing used in the present invention is a process that makes the inside of a convex part and a concave part not solid but hollow.

  The individual planar cross-sectional shapes of the convex portion and the concave portion can be a square, a rectangle, a circle, an ellipse, an oval, or any other shape. Further, the three-dimensional shape of the convex portion and the concave portion can be a pyramid shape, a conical shape, or any other shape. Moreover, although the top part of a convex part and a recessed part may be a sharp shape, in order to stabilize a contact state with the other party member, it is preferable to make it spherical shape and flat plane shape (so-called fringe surface shape).

  Note that the three-dimensional shape and planar shape of the convex and concave portions, for example, the planar diameter in plan view, the center-to-center pitch in plan view, etc., determine how much the amount of air in the air layer is set, and the interface reflection area. An appropriate value is set based on how much it is set. The plane diameter is a diameter in the case of a circle and a diagonal length in the case of a rectangle. The height from the raised part of the convex part and the concave part to the top part is appropriately set according to the thickness of the film. Usually, the height is preferably 0.2 μm or more.

  The base material used in the light reflector according to the present invention can be formed of a white reflective film that reflects light. Thereby, white light can be reflected by the light reflector. The white reflective film is a film formed of a synthetic resin containing a white pigment or fine bubbles in a dispersed state. Examples of the synthetic resin include polyethylene terephthalate, polyethylene naphthalate, acrylic resin, polycarbonate, polystyrene, polyolefin, cellulose acetate, weather resistant vinyl chloride, and the like. Preferably, polyethylene terephthalate having excellent heat resistance is used.

  The base material used in the light reflector according to the present invention may be a base material having a silver layer or an aluminum layer on the surface facing the film. The film used in the light reflector according to the present invention can be a film having a silver layer or an aluminum layer on the surface facing the substrate. Thus, specular reflection can be performed by the light reflector.

  In the light reflector according to the present invention, the film is preferably a translucent film. Translucency is a property that allows light to pass through. The case where the maximum amount of light is transmitted is “transparent”. When the film is a translucent film, the translucent film can reflect high brightness light in the context of an air layer formed between the film and the substrate.

  Next, a planar light source device according to the present invention includes a light source that emits light, a light guide that receives light from the light source from one surface and emits it from a light emitting surface that is the other surface, and the light guide. And a light reflector provided opposite to the surface opposite to the light emitting surface of the body, and the light reflector is a light reflector having the above-described configuration.

According to the planar light source device having this configuration, since the plurality of protrusions are provided on the base material that is a component of the light reflector, the light reflector is prevented from being in close contact with the light guide body that is the counterpart member. Therefore, it is possible to prevent the occurrence of uneven brightness.
Also, a plurality of protrusions are formed on the substrate by the protrusions and / or recesses formed on the film laminated on the light reflector substrate, and the protrusions are formed by particles, beads, etc. In the first place, there is no situation where the light guide body is damaged by dropping off of beads or the like.

  In addition, since an air layer is formed inside the plurality of protrusions protruding on the base material, the individual hardness or rigidity of the plurality of protrusions can be appropriately adjusted. It is possible to surely prevent the light guide body contacting the part from being damaged.

  Furthermore, since the convex part and / or the recessed part are formed in the film laminated | stacked on a base material, when opposing member (for example, light guide) is arrange | positioned facing a light reflector, a light reflector and a counterpart member Many air chambers are formed between the two. Therefore, when an electronic device (for example, a liquid crystal display device) including the light reflector and the counterpart member receives pressure from the front and back, the pressure can be dispersed in the light reflector. For this reason, compared with the conventional apparatus which did not interpose an air chamber, it became easy to maintain the initial characteristic of an electronic device.

According to the light reflector according to the present invention, since the plurality of projecting portions are provided on the base material, the light reflector can be prevented from coming into close contact with the mating member. For this reason, when the counterpart member is a light guide, it is possible to prevent the light emitted from the light guide from causing uneven brightness.
In addition, a plurality of protrusions are formed on the base material by the protrusions and / or recesses formed on the film laminated on the base material, and the protrusions are formed by particles, beads, etc. Therefore, the situation where the mating member is damaged by dropping off the beads or the like does not occur in the first place.

  In addition, since an air layer is formed inside the plurality of protrusions protruding on the base material, the individual hardness of the plurality of protrusions or the case where the protrusions are solid or Rigidity can be adjusted appropriately, so that it is possible to reliably prevent the mating member such as the light guide that contacts the protruding portion from being damaged.

  Further, when the film laminated on the substrate has a convex portion and / or a concave portion, when the counterpart member (for example, a light guide) is disposed facing the light reflector, the light reflector A number of air chambers are formed between the mating member and the mating member. Therefore, when an electronic device (for example, a liquid crystal display device) including the light reflector and the counterpart member receives pressure from the front and back, the pressure can be dispersed in the light reflector. For this reason, compared with the conventional apparatus which did not interpose an air chamber, it became easy to maintain the initial characteristic of an electronic device.

  In the planar light source device according to the present invention, the light guide is disposed so as to face the light reflector according to the present invention, and the light from the light source is introduced into the light guide. The light is reflected by the light reflector and emitted from the light exit surface of the light guide to the outside. Since the planar light source device includes the light reflector according to the present invention, the planar light source device can similarly exhibit the effects exhibited by the above-described light reflector.

It is sectional drawing of the principal part of one Embodiment of the planar light source device using the light reflection body which concerns on this invention, (a) is a figure which shows the said part in an exploded state, (b) is assembling the said part FIG. It is a figure which shows a part of film which is a component of the light reflector shown in FIG. 1, (a) is a top view, (b) is sectional drawing according to the BB line in (a). . It is sectional drawing of the principal part of other embodiment of the planar light source device using the light reflection body which concerns on this invention, (a) is a figure which shows the said part in an exploded state, (b) is the said part. It is a figure which shows the assembled state. It is a figure which shows a part of film which is a component of the light reflector shown in FIG. 3, (a) is a top view, (b) is sectional drawing according to CC line in (a). . It is sectional drawing of the principal part of other embodiment of the planar light source device using the light reflection body which concerns on this invention, (a) is a figure which shows the said part in an exploded state, (b) is the said part It is a figure which shows the state which assembled. It is a figure which shows a part of film which is a component of the light reflector shown in FIG. 5, (a) is a top view, (b) is sectional drawing according to the DD line in (a). . (C) is sectional drawing of the principal part of further another embodiment of the planar light source device using the light reflector which concerns on this invention, (b) is a figure which shows the said part in an exploded state, (a ) Is a cross-sectional view showing a part of a film which is a component of a light reflector. It is a perspective view which shows other embodiment of the planar light source device using the light reflection body which concerns on this invention. It is a perspective view which shows other embodiment of the planar light source device using the light reflection body which concerns on this invention.

(First embodiment of light reflector and planar light source device)
A first embodiment of the present invention will be described with reference to FIGS.
In FIG. 1A, the planar light source device 1 includes a light reflector 2 and a light guide 3. The light reflector 2 has a base material 4 and a film 5. The film 5 is adhered to the base material 4 by the adhesive layer 6. An adhesive layer may be used in place of the adhesive layer 6.

  After the assembly of the planar light source device 1 is completed, the lower surface 3a of the light guide 3 in contact with the upper end surface of the film 5 is brought into contact as shown in FIG. The film 5 and the light guide 3 are in contact with each other, but are not attached by an adhesive or the like. The base material 4 and the film 5 have an area slightly larger than a display screen of an electronic device to be used, for example, a liquid crystal display device.

  The substrate 4 is formed of a foamed white film, a metal vapor deposition film, a white pigment kneaded film, a white paint film, or the like. Examples of white pigments include titanium oxide, barium sulfate, and calcium carbonate. The thickness of the base material 4 is, for example, 1 to 250 μm, preferably 5 to 200 μm, and particularly preferably 10 to 200 μm.

  Synthetic resins forming the substrate 4 are, for example, polyesters such as polyethylene terephthalate and polyethylene naphthalate; polycarbonates such as bisphenol A polycarbonate; polyethylene, polypropylene, cyclic olefin copolymer, ethylene-vinyl acetate copolymer, and the like. Polyolefins; cellulose derivatives such as cellulose triacetate; vinyl resins such as polyvinylidene chloride and polyvinyl butyral; polystyrenes; polyimides; polyamides such as nylon; polyethersulfone; polysulfone resin; Fluororesin; Polyetheretherketones; Polyurethanes; Polyacrylic acid; Polyacrylic acid esters; Polymethacrylic acid; Polymethacrylic acid esters; Polyacrylonitrile Nitriles such as polymethacrylonitrile polyacrylonitrile; polyethers such as polyethylene oxide, epoxy resins, polyvinyl alcohols; polyacetals such as PVA; and the like. In particular, polyesters such as polyethylene terephthalate, polycarbonates, and polyamides are preferable.

  The film 5 is made of, for example, polyethylene terephthalate, polycarbonate, acrylic, or the like. The material forming the film 5 is preferably a translucent material, desirably a colorless and transparent material. As shown in FIG. 2A and FIG. 2B, the film 5 has a plurality of convex portions 7 formed by embossing. During embossing, a space 8 is formed inside the convex portion 7. In addition, the processing method for forming the convex part 7 is not restricted to embossing. The thickness of the film 5 is set to an appropriate thickness based on the required size of the space 8 and the required elastic force of the convex portion 7. For example, the film 5 is a film made of a synthetic resin having a thickness of 12 to 50 μm, particularly 25 μm. is there.

  In this embodiment, a convex part is a part which made the film protrude upwards with a convex lower metal mold | die at the time of embossing. This convex part is a part which protrudes in the direction away from the base material 4 when the film 5 is stuck to the base material 4 as shown to Fig.1 (a). The plurality of convex portions 7 are arranged in a lattice shape in plan view. The lattice shape is an arrangement state in which a plurality of rows are formed in respective directions in two orthogonal directions (two vertical and horizontal directions in FIG. 2A). Of course, the arrangement state of the convex portions 7 is not limited to the lattice shape, and may be any other arrangement state.

  The shape of the convex portion 7 is an appropriate shape based on the required size of the space 8, the required elastic force of the convex portion 7, and the like. In the present embodiment, the shape of the convex portion 7 is adjusted to a desired shape by the shape of the embossing mold and the embossing pressure. In the present embodiment, the convex shape of the lower mold is a quadrangular pyramid having a top surface of 100 to 200 μm and a bottom surface of 400 μm. The completed convex portion 7 has substantially the same shape as the mold. That is, the planar shape of the convex part 7 is a square. However, due to embossing, the four corners are appropriately rounded (circular). The plane diameter of the largest portion (the bottom portion in the embodiment) of the convex portion 7 is approximately 400 μm. The plane diameter is the diagonal length of a square. The height from the rising part of the convex part 7 to the top part is an arbitrary value of 0.2 μm or more.

  As shown in FIG. 1A, the film 5 is bonded to the base material 4 by the adhesive layer 6. Conventionally known adhesives can be used as the adhesive. Also, conventionally known bonding methods can be used as the bonding method.

  The film 5 is bonded to the base material 4 so that the convex portion 7 protrudes in a direction away from the base material 4. When the film 5 is bonded to the substrate 4, a protruding portion 9 that is a portion protruding on the substrate 4 is formed by the protruding portion 7 itself. Since the inside of the convex portion 7 is a space, when the film 5 is bonded to the base material 4, an air layer A is formed inside the protruding portion 9. Since the periphery of the bottom of the convex portion 7 is adhered to the base material 4 by the adhesive layer 6, the air layer A is airtightly closed from the outside.

  The light guide 3 is formed of a translucent resin, preferably a colorless and transparent resin. Examples of such a resin include polycarbonate resin and acrylic resin. The light guide 3 has an effect of receiving light emitted from a light source (not shown) and emitting the light from the light emitting surface as planar light. The light emitting surface is a surface (not shown) opposite to the surface 3 a in contact with the film 5. The light introduced into the light guide 3 is reflected by each wall surface (not shown) of the light guide 3 itself including the one surface 3a, or reflected by the base material 4 through the one surface 3a. Then, the light travels inside the light guide 3 and finally exits from the light exit surface which is the opposite surface of the surface 3a.

  If the light reflector 2 is a simple flat plate that does not have the protruding portion 9 (the convex portion 7 in this embodiment), the light guide 3 and the flat plate may be in close contact with each other, which may cause uneven brightness in the emitted light. There is. On the other hand, in this embodiment, since the some protrusion part 9 is provided on the base material 4, it can prevent that the light reflection body 2 adheres to the moving body 3 which is a counterpart member. Therefore, it is possible to prevent uneven brightness from occurring in the light emitted from the light guide 3.

  Further, in the present embodiment, a plurality of protruding portions 9 are formed on the base material 4 by the convex portions 7 formed on the film 5 laminated on the base material 4, and are protruded by particles, beads or the like. Since the shape portion is not formed, a situation in which the counterpart member is damaged by dropping off the beads or the like does not occur in the first place.

  In addition, since the closed air layer A is formed inside the plurality of protruding portions 9 protruding on the base material 4, the plurality of protruding shapes are formed as compared with the case where the protruding portion 9 is solid. The individual hardness or rigidity of the portion 9 can be adjusted appropriately, and therefore, the light guide 3 that contacts the protruding portion 9 can be reliably prevented from being damaged.

  Furthermore, since the convex part 7 is formed in the film 5 laminated | stacked on the base material 4, many air chambers are formed by the convex part 7 between the light reflector 2 and the light guide 3. FIG. Therefore, when an electronic device (for example, a liquid crystal display device) including the light reflector 2 and the light guide 3 receives pressure from the front and back, the pressure can be dispersed in the light reflector 2. For this reason, compared with the conventional apparatus which did not interpose an air chamber, it became easy to maintain the initial characteristic of an electronic device.

(Modification)
In the above embodiment, as shown in FIG. 2A, the plurality of convex portions 7 are arranged in a lattice shape in a plan view, that is, a pattern arranged in a plurality of rows along each of two orthogonal directions. Instead of this, the plurality of convex portions 7 may be arranged in an arbitrary pattern other than a lattice shape, or may be arranged randomly (disordered) in a plane.

(Second Embodiment of Light Reflector and Planar Light Source Device)
FIG. 3 shows a light reflector 12 and a planar light source device 21 using the same according to another embodiment of the present invention. FIG. 4 shows a film 15 used in the light reflector 12.
In the said 1st Embodiment, as shown to Fig.2 (a) and FIG.2 (b), the convex part 7 was formed in the film 5. FIG. Then, as shown in FIG. 1A, the film 5 was bonded to the base material 4 so that the convex portion 7 protruded in a direction away from the base material 4. Thereby, in the light reflector 2, the protruding portion 9 having the air layer A therein was formed by the protruding portion 7 itself.

  On the other hand, in this embodiment, as shown in FIG. 4A and FIG. 4B, the recess 11 is formed on the film 15 by embossing. A recessed part is the part which made the film protrude below with a convex upper metal mold | die at the time of embossing. Then, as shown in FIG. 3A, the film 15 was bonded to the base material 4 so that the bottom of the recess 11 was bonded to the base material 4. Thereby, in the light reflector 12, a protruding portion 9 having an air layer A inside is formed around the outside of the recess 11. The material of the film 15 is the same as that of the film 5 in FIG.

  Since the recess 11 is formed by embossing one synthetic resin sheet, the inside of the protruding portion 9 around the recess 11 is a space. Therefore, when the film 15 is bonded to the base material 4, an air layer A is formed inside the protruding portion 9. The periphery of the bottom of the protruding portion 9 is bonded to the base material 4 by the adhesive layer 6.

  Also in this embodiment, since the several protrusion part 9 is provided on the base material 4, it can prevent that the light reflection body 2 adheres to the moving body 3 which is a counterpart member. Therefore, it is possible to prevent uneven brightness from occurring in the light emitted from the light guide 3.

  In the present embodiment, a plurality of protrusions 9 are formed on the substrate 4 by the recesses 11 formed on the film 15 laminated on the substrate 4, and the protrusions 9 are formed by particles, beads, or the like. Since the portion is not formed, the situation that the mating member is damaged by dropping off the beads or the like does not occur in the first place.

  In addition, since the air layer A is formed inside the plurality of protruding portions 9 protruding on the base material 4, the plurality of protruding portions 9 are compared with the case where the protruding portions 9 are solid. The individual hardness or rigidity can be adjusted appropriately, so that it is possible to reliably prevent the light guide 3 that contacts the protrusion 9 from being damaged.

  Furthermore, since the recesses 11 are formed in the film 15 laminated on the substrate 4, a large number of air chambers are formed by the recesses 11 between the light reflector 12 and the light guide 3. Therefore, when an electronic device (for example, a liquid crystal display device) including the light reflector 12 and the light guide 3 receives pressure from the front and back, the pressure can be dispersed in the light reflector 12. For this reason, compared with the conventional apparatus which did not interpose an air chamber, it became easy to maintain the initial characteristic of an electronic device.

(Third embodiment of light reflector and planar light source device)
FIG. 5 shows a light reflector 22 and a planar light source device 31 using the same according to still another embodiment of the present invention. FIG. 6 shows a film 25 used in the light reflector 22.
In the first embodiment, as shown in FIGS. 2 (a) and 2 (b), the projection 5 is formed on the film 5, and further, as shown in FIG. By bonding to the material 4, the protruding portion 9 having the air layer A inside was formed by the protruding portion 7 itself in the light reflector 2.

  Moreover, in the said 2nd Embodiment, as shown to Fig.4 (a) and FIG.4 (b), the recessed part 11 is formed in the film 15, and also as shown to Fig.3 (a), the film 15 is formed. By adhering to the base material 4, in the light reflector 12, the protruding portion 9 having the air layer A inside was formed around the outside of the convex portion 7.

  In contrast, in this embodiment, as shown in FIGS. 6A and 6B, both the convex portions 7 and the concave portions 11 are alternately formed on the film 25 by embossing. Then, as shown in FIG. 5A, the film 25 was bonded to the base material 4 so that the bottom of the recess 11 was bonded to the base material 4. Thereby, in the light reflector 22, the protruding portion 9 having the air layer A inside is formed around the outside of the concave portion 11 and inside the convex portion 7. The material of the film 25 is the same as that of the film 5 in FIG.

  Since the convex portion 7 and the concave portion 11 are formed by processing one synthetic resin sheet by embossing, the inside of the convex portion 9 formed around the concave portion 11 inside the convex portion 7 is It is space. Therefore, when the film 25 is bonded to the base material 4, an air layer A is formed inside the protruding portion 9. The periphery of the bottom of the protruding portion 9 is bonded to the base material 4 by the adhesive layer 6.

  Also in this embodiment, since the several protrusion part 9 is provided on the base material 4, it can prevent that the light reflection body 2 adheres to the moving body 3 which is a counterpart member. Therefore, it is possible to prevent uneven brightness from occurring in the light emitted from the light guide 3.

  In the present embodiment, a plurality of protruding portions 9 are formed on the base material 4 by the convex portions 7 and the concave portions 11 formed on the film 25 laminated on the base material 4. Since the projecting portion is not formed by, for example, a situation in which the counterpart member is damaged by dropping off the beads or the like does not occur in the first place.

  In addition, since the air layer A is formed inside the plurality of protruding portions 9 protruding on the base material 4, the plurality of protruding portions 9 are compared with the case where the protruding portions 9 are solid. The individual hardness or rigidity can be adjusted appropriately, so that it is possible to reliably prevent the light guide 3 that contacts the protrusion 9 from being damaged.

  Furthermore, since the convex part 7 and the recessed part 11 are formed in the film 25 laminated | stacked on the base material 4, between the light reflector 22 and the light guide 3, the convex part 7 and the recessed part 11 make many air chambers. Is formed. Therefore, when an electronic device (for example, a liquid crystal display device) including the light reflector 22 and the light guide 3 receives pressure from the front and back, the pressure can be dispersed in the light reflector 12. For this reason, compared with the conventional apparatus which did not interpose an air chamber, it became easy to maintain the initial characteristic of an electronic device.

(Fourth Embodiment of Light Reflector and Planar Light Source Device)
FIG. 7 shows a film 35, a light reflector 32, and a planar light source device 41, which are still another embodiment of the present invention.
In FIG. 7A, the film 35 used in the light reflector of the present embodiment is not formed by a single synthetic resin film, but is formed by laminating a reflective layer 34 on a single synthetic resin film 33. It is formed as a composite film. The reflective layer 34 is made of, for example, silver (Ag), aluminum (Al), or the like. Ag, Al, and the like are laminated on the synthetic resin film 33 by vapor deposition, for example. The frame 35 has a plurality of convex portions 7 formed by embossing. The convex part 7 is embossed so that the layer of the reflective film 34 is on the inside.

  As shown in FIG. 7B, the film 35 is bonded to the surface of the base material 4 by the adhesive layer 6 so that the convex portions 7 protrude in a direction away from the base material 4. Due to this adhesion, a plurality of protruding portions 9 are formed on the substrate 4 by the convex portions 7 themselves. A closed air layer A is provided between the protruding portion 9 and the base material 4. In the present embodiment, the light emitted from the one surface 3 a of the light guide 3 is reflected by the reflection film 34 that is a constituent element of the film 35 and is again introduced into the light guide 3. For this reason, the base material 4 can also be formed with the material which does not have the function of light reflection or light scattering.

  In the above embodiment, the reflective film 34 is provided on the surface of the film 35 on the substrate 4 side. Alternatively, the reflective film 34 may be provided on the surface of the substrate 4 on the film 35 side.

(Fifth Embodiment of Light Reflector and Planar Light Source Device)
FIG. 8 shows a light reflector 52 and a planar light source device 51 using the same according to still another embodiment of the present invention. The planar light source device 51 is used as a backlight for a liquid crystal display device which is an electronic device, for example. The planar light source device 51 includes a light reflector 52, a light guide 3, light collectors 53 a and 53 b, and a diffusion plate 54. A white LED (Light Emitting Diode) 55 that is a light emission source is provided facing one side surface of the light guide 3. A plurality of LEDs 55 are provided along the side surface of the light guide 3. Reference symbol L indicates a planar light emission region. The light emission source may be a CCFL (cold cathode tube).

  The light reflector 52 can be constituted by the light reflector 2 in FIG. 1, the light reflector 12 in FIG. 3, the light reflector 22 in FIG. 5, or the light reflector 32 in FIG. The light reflector 52 is preferably a white (transparent) light reflector having no silver or aluminum reflective layer. Two light collecting plates 53a and 53b are provided so as to face the light emitting surface of the light guide 3 (that is, the surface opposite to the surface facing the light reflector 52). A plurality of prisms having a triangular cross section are provided in parallel to each other on the light emitting side surface of the light collecting plate 53a on the light guide 3 side. A plurality of prisms having a triangular cross-section are also provided in parallel to each other on the light incident side surface of the light collector 53 b far from the light guide 3. The prism on the light collecting plate 53a side and the prism on the light collecting plate 53b side extend linearly in directions orthogonal to each other.

  The light emitted from the LED 55 is introduced into the light guide 3 from the side surface of the light guide 3 facing the LED 55, travels through the light guide 3, and then the light exit surface of the light guide To the outside. A part of the light that enters the light guide 3 exits from the bottom surface, is reflected by the light reflector 52, and is then introduced into the light guide 3 again. The light emitted from the light emitting surface of the light guide 3 is collected by the light collecting plates 53a and 53b, and further emitted from the planar light emitting region L while being diffused by the diffusion plate 54.

(6th Embodiment of a light reflector and a planar light source device)
FIG. 9 shows a light reflector 52 and a planar light source device 61 using the same, which is still another embodiment of the present invention. The planar light source device 61 is also used as a backlight for a liquid crystal display device which is an electronic device, for example. In FIG. 9, the same members as those in FIG. 8 are denoted by the same reference numerals, and the description thereof is omitted.

  This planar light source device 61 is different from the planar light source device 51 shown in FIG. 8 in that the light collecting plate 53a on the light guide 3 side in FIG. 8 is omitted and one light collecting plate in FIG. Only 53 is provided, and a plurality of prisms having a triangular cross section are provided in parallel to each other on the light emitting surface of the light guide 3 itself. The plurality of prisms are simultaneously formed when the light guide 3 is formed by molding. The prism on the light guide 3 side and the prism on the light collecting plate 53 side extend linearly in directions orthogonal to each other. The prism of the light guide 3 may be provided on the lower surface, that is, the surface opposite to the light emitting surface.

  The light reflector 52 can be constituted by the light reflector 2 in FIG. 1, the light reflector 12 in FIG. 3, the light reflector 22 in FIG. 5, or the light reflector 32 in FIG. The light reflector 52 of this embodiment is preferably a specular reflection type light reflector having a reflective layer of silver or aluminum.

  The light emitted from the LED 55 is introduced into the light guide 3 from the side surface of the light guide 3 facing the LED 55, travels through the light guide 3, and then the light exit surface of the light guide To the outside. A part of the light that enters the light guide 3 exits from the bottom surface, is reflected by the light reflector 52, and is then introduced into the light guide 3 again. Light emitted from the light exit surface of the light guide 3 is condensed in one direction by a prism provided on the light exit surface of the light guide 3. The light emitted from the light emitting surface of the light guide 53 is condensed in one other direction by the light collecting plate 53 and then emitted from the planar light emitting region L to the outside while being diffused by the diffusion plate 54. .

1. 1. a planar light source device; 2. a light reflector; 3. light guide; 4. base material; the film,
6). 6. adhesive layer; Convex part, 8. Space, 9. 10. protrusions, Recess,
12 14. light reflector, Film, 22. Light reflector, 25. the film,
31. Planar light source device, 32. Light reflector, 33. Synthetic resin film, 34. Reflective layer,
35. Film, 41. Planar light source device 51. Planar light source device, 52. Light reflector,
53a, 53b. Light collecting plate, 54. Diffusion plate, 55. LED, 61. Surface light source device,
63. Light collector, A. Air layer, L. Light exit area

Claims (8)

A substrate;
Having a film adhered to the substrate by an adhesive layer or an adhesive layer;
The film has a plurality of convex portions and / or concave portions having a space inside,
A plurality of projecting portions are formed by the convex portions and / or the concave portions between the base material and the film in a state where the film is adhered to the base material,
A light reflector characterized in that the inside of the plurality of protrusions forms an air layer.   The light reflector according to claim 1, wherein the convex part and / or the concave part are provided in a dot shape with a space in plan view.   3. The light reflector according to claim 1, wherein the convex portion and / or the concave portion are provided side by side so as to form a plurality of rows in each of two orthogonal directions.   The said convex part and / or a recessed part are formed by the embossing using a press die, The light reflector as described in any one of Claims 1-3 characterized by the above-mentioned.   The light reflector according to any one of claims 1 to 4, wherein the base material is a white reflective film that reflects light.   The silver layer or the aluminum layer is provided in the surface facing the said film of the said base material, or the surface facing the said base material of the said film, In any one of Claims 1-4 characterized by the above-mentioned. The light reflector described.   The light reflector according to claim 1, wherein the film is a light-transmitting film. A light source that emits light;
A light guide that receives the light from the light source from one surface and emits it from the light exit surface, which is the other surface;
A light reflector provided facing the surface opposite to the light exit surface of the light guide,
The planar light source device according to any one of claims 1 to 7, wherein the light reflector is the light reflector according to any one of claims 1 to 7.

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