JP5108623B2 - Light guide device and manufacturing method thereof - Google Patents

Description

  The present invention relates to an illumination device using a light guide and a method for manufacturing the same, and more particularly to a light guide device including means for realizing ease of manufacture and high-intensity light extraction and a method for manufacturing the same.

As a light guide device using a light guide, there are, for example, the following patent documents.
The illumination device described in Patent Document 1 is configured such that a light guide unit having a higher refractive index than that of the substrate is formed on the upper part of the substrate, and the periphery of the light guide unit is covered with a low refractive unit. Furthermore, the surface of the light guide is roughened, a light diffusing body is dispersed inside the light guide, or a high refractive part is formed in layers on the low refractive part to scatter and guide light. The light part emits light.

  In the illumination device described in Patent Document 2, a small hole called a dot portion is formed in the cladding portion on the core portion of the optical waveguide, and the light that propagates through the core portion leaks when the light leaks from the small hole. It illuminates the irradiated body.

Patent Document 3 discloses that a light scattering layer is formed on the lower surface of the light guide plate, thereby reducing luminance loss of light emitted from the light guide and further forming a uniform light emitting surface.
Japanese Patent Laid-Open No. 3-171009 JP-A-3-296089 JP-A-10-31115

  However, the method described in Patent Document 1 has a problem that it is difficult to reduce the cost because a process for separately creating a light guide member that generates scattering is required.

  In addition, since the amount of light incident from the incident end face of the core portion is gradually lost as it moves away from the incident end face, the light emitting surface can be extracted with uniform brightness unless the degree of scattering changes according to the distance. There is also a problem that it is difficult to realize.

  On the other hand, in the thing of patent document 2, since much light which faces in a diagonal direction is formed in a light-scattering layer, when the surface of a cladding part is seen brightly from the diagonal direction, on the other hand, the cladding part was seen from right above. There is a problem that the luminance at that time tends to be insufficient.

  Furthermore, in the thing of patent document 3, although the whole light-guide plate can be illuminated, it is inadequate with respect to the request | requirement of illuminating a part of light-guide plate partially brighter than those circumference | surroundings. There is a problem that.

  The present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide a light guide device that is easy to manufacture and realizes high luminance extraction and a method for manufacturing the same.

The present invention has a laminate comprising a substrate, a clad layer laminated on the substrate, and a core layer laminated on the clad layer, and light incident on the core layer is incident on the core layer In the light guide device that travels inside and is emitted toward the outside from the surface of the core layer,
An opening is formed in the cladding layer, a part of the synthetic resin forming the core layer enters the opening,
A light extraction portion that reflects light incident on the base material facing at least the opening to a specific direction or diffusely reflects or scatters within a predetermined spread angle is formed on the base material .
In the light extraction portion, incident light on the base material is directed at an angle emitted from the surface of the core layer.

  In the present invention, since the light propagating in the core layer can be directly incident on the light extraction portion through the opening without passing through the cladding layer, it is reflected, irregularly reflected, or scattered at the light extraction portion. Light can be efficiently extracted outside. For this reason, it becomes possible to extract light with high luminance.

  In the above, it is preferable that the light extraction portion is formed on the surface of the base material in contact with the clad layer or the back surface on the opposite side. For example, a convex prism is formed on the surface of the base material. The reflection layer is formed on the surface including the prism.

  The base material preferably has translucency. For example, a concave prism is formed on the back surface of the base material, and a reflective layer is formed on the back surface including the prism.

Furthermore, it is preferable that the reflective layer is formed of a half mirror.
With the above means, light can be transmitted and reflected, so that it is possible to form the core layer and the clad layer using a UV curable resin that is cured when irradiated with ultraviolet rays.

Moreover, the said light extraction part may be formed in the said base material, for example, the said base material is formed from the translucent synthetic resin which mixes an inorganic filler inside.
In the above means, light can be scattered inside the substrate.

Moreover, the manufacturing method of the light guide device of the present invention includes a first step of forming a light extraction portion that reflects, irregularly reflects, or scatters incident light on the surface of the base material,
A second step of forming a clad layer provided with an opening corresponding to the light extraction portion;
Forming a core layer for propagating the light,
After laminating the clad layer on the base material and further laminating the core layer on the clad layer, the base material, the clad layer and the core layer are integrated by heating and pressing. A third step of allowing a part of the resin forming the core layer to enter the opening ,
It is characterized by having .
Further, instead of the third step, a clad layer is laminated on the base material in a predetermined mold, and a liquid thermosetting resin is coated on the clad layer. The step of integrating the base layer, the clad layer, and the core layer formed of the thermosetting resin by pressurizing and allowing a part of the thermosetting resin to enter the opening. It can be.
With the above means, the light guide device can be easily manufactured.

Furthermore, instead of the third step, a clad layer is laminated on the base material in a predetermined mold, and after coating a liquid UV curable resin on the clad layer, The step of integrating the base layer, the clad layer, and the core layer formed of the UV curable resin by irradiating ultraviolet rays, and allowing a part of the UV curable resin to enter the opening. Can have.
With the above means, the process speed can be increased.

Further, the present invention forms a light extraction portion that reflects, diffusely reflects, or scatters light incident on the base material by transferring a plurality of prisms having a predetermined shape to the back surface of the base material made of a translucent resin sheet. Step (1) ,
Forming a cladding layer having an opening that faces the radiation exit part of light to be emitted to the outside from the core layer be one totally reflected toward the core layer on a surface of the substrate (2) When,
Forming the core layer for propagating light on the cladding layer, and allowing a part of the resin forming the core layer to enter the opening (3),
The method includes a step of forming a reflective layer on the back surface of the base material.

  In the step (2), a liquid UV curable resin is coated in a predetermined mold, the surface of the substrate is set, and the UV curable resin is cured by irradiating ultraviolet rays. Then, a cladding layer having an opening can be formed by performing die cutting thereafter.

Further, in the step (3), the core layer is formed by coating the liquid UV curable resin on the cladding layer and curing the UV curable resin by irradiating ultraviolet rays. be able to.

The light guide device of the present invention can be easily manufactured and can extract high-luminance light.
In the manufacturing method of the present invention, the light guide device can be manufactured by a simple method, and as a result, the time required for the manufacturing can be greatly shortened.

  FIG. 1 is a perspective view showing a basic configuration of a light guide device as an embodiment of the present invention, and FIG. 2 is an exploded perspective view of FIG.

  A light guide device 1 shown in FIG. 1 and below is used as a member for illuminating operation buttons provided on, for example, a mobile phone.

  Note that “irregular reflection” in the present invention is defined as a phenomenon in which light diffuses in various directions at these boundary surfaces when light enters the second medium from the first medium. Further, “scattering” is defined as a light dispersion phenomenon caused by collision with other molecules contained in the medium when the light passes through the medium.

  As shown in FIG. 2, the light guide device 1 of the present invention includes a base material 2 provided in the lowermost layer, a clad layer 3 laminated on the upper layer of the base material 2, and a core layer provided in the upper layer. 4 is formed as a laminated body 1A laminated in the thickness direction. On the Y1 side of the laminated body 1A, a light source 5 made of an LED or the like is disposed so as to oppose.

  The uppermost core layer 4 is formed as a thin film member of a synthetic resin excellent in translucency such as silicone resin and urethane resin. The end surface on the Y1 side of the core layer 4 has an incident surface 4a formed as a smooth surface, and the exit surface 5a of the light source 5 is disposed opposite to the incident surface 4a.

  In this embodiment, the surface of the core layer 4 is in contact with air. The air forms an error cladding having a lower refractive index than the core layer 4. Alternatively, the surface cladding (not shown) may be formed by masking the surface of the core layer 4 with a material having a refractive index lower than that of the core layer 4.

  The clad layer 3 is formed of a synthetic resin having a lower refractive index than that of the core layer 4, such as a fluorine-based polymer and silicone. A plurality of openings 3 a, 3 a, 3 a are formed in the cladding layer 3, and these openings 3 a, 3 a, 3 a are opposed to the light extraction part 2 a formed in the substrate 2.

  3A and 3B show a first embodiment of the light extraction unit, where FIG. 3A is a cross-sectional view of a light guide device showing a first example of the first embodiment, and FIG. 3B is a first embodiment. Sectional drawing of the light guide apparatus which shows the 2nd example of a form, (C) is sectional drawing of the light guide apparatus which shows the 3rd example of 1st Embodiment.

  As the light extraction portion 2a, for example, a metal film 6 is formed on the surface 2A of the base material 2 as shown in FIG. 3A, and a dod pattern 7 is printed with a white material (first) Example), a metal film 6 and white material printed in a predetermined pattern on the surface of the substrate 2 as shown in FIG. 3B (second example), or as shown in FIG. A prism (fine convex portion) 8 is formed on the surface 2A of a simple substrate 2 and a half mirror 6A made of a thin metal film is formed thereon (third example).

  In the light guide device 1 shown in the first to third examples of the first embodiment, the synthetic resin that forms the core layer 4 enters each opening 3a that forms the cladding layer 3, and the opening The core layer 4 and the light extraction part 2a are in direct contact with each other through 3a.

  Light emitted from the light source 5 and incident into the core layer 4 from the incident surface 4a is repeatedly totally reflected between the lower surface side cladding layer 3 and the upper surface side air cladding (air layer) or surface cladding, and then the light source 5 It proceeds in the core layer 4 in the Y2 direction away from the center.

  When the totally reflected light reaches the opening 3a formed in the cladding 3, the light is reflected in a specific direction at the boundary surface between the core layer 4 and the light extraction portion 2a, or has a predetermined spread angle. Diffuse reflection in various directions within the range.

  A part of the reflected or irregularly reflected light is incident on an interface between the core layer 4 having a high refractive index and an air clad (air layer) or a surface clad having a low refractive index. At this time, the light incident at a critical angle or less with respect to the boundary surface passes through the core layer 4 and is emitted to the upper air layer. Thereby, when the surface of the core layer 4 is viewed from above, the surface of the core layer 4 facing the opening 3a appears to be partially brighter than their surroundings.

  In the first to third examples of the first embodiment, since the clad layer 3 is not interposed between at least the light extraction portion 2a and the core layer 4, the light propagating in the core layer 4 is directly extracted. It is possible to reach the part 2a and efficiently diffuse light.

  The light extraction portion 2a only needs to be formed at least at a position facing the opening 3a of the cladding layer 3. However, as shown in the second embodiment below, the light extraction portion 2a is formed over the entire surface of the substrate 2. It can also be set as the aspect formed like this.

  4A and 4B show a second embodiment of the light extraction unit, where FIG. 4A is a sectional view of a light guide device showing a first example of the second embodiment, and FIG. 4B is a second embodiment. Sectional drawing of the light guide device which shows the 2nd example of a form, (C) is a perspective view of the light guide device which shows the 3rd example of 2nd Embodiment.

  FIG. 4A shows a case where the surface of the base material 2 is printed uniformly in white, or as a scattering pattern, for example, a grating or a dot pattern composed of fine irregularities is formed uniformly. (First example of the second embodiment). FIG. 4B shows a case where the base material 2 itself is formed of a white material (second example of the second embodiment). Further, FIG. 4C shows a case where the size of the opening 3a is changed according to the distance from the light source 5 (third example of the second embodiment).

  In the light guide device 1 shown in the first to third examples of the second embodiment, as in the first embodiment, when the surface of the core layer 4 is viewed from directly above, it faces the opening 3a. The surface of the core layer 4 becomes partially brightly illuminated compared to their surroundings.

  In the light guide device 1 shown in the first to third examples of the second embodiment, the light extraction portion 2 a is uniformly formed over the entire surface of the base material 2. For this reason, uniform illumination can be achieved only by considering the patterning of the clad layer 3 provided thereon.

  For example, in the third example of the second embodiment shown in FIG. 4C, the diameter dimension of each opening 3a formed in the cladding layer 3 is made smaller on the side closer to the light source 5. However, it is formed so as to increase as the distance from the light source 5 increases. In this way, the influence of the distance between the light source 5 and the light extraction portion 2a can be eliminated, and the brightness in each light extraction portion 2a can be made uniform when the surface of the core layer 4 is viewed from above. It becomes possible. If the diameter of each opening 3a is constant, the same effect can be obtained even if the number of openings 3a is small on the light source 5 side and increases as the distance from the light source 5 increases. Is possible.

Next, the case where translucent or semi-translucent resin is used for the base material 2 is demonstrated.
5A and 5B show a third embodiment of the light extraction unit, where FIG. 5A is a cross-sectional view of a light guide device showing a first example of the third embodiment, and FIG. 5B is a third embodiment. It is sectional drawing of the light guide apparatus which shows the 2nd example of a form.

  A light guide device 1 shown as a first example of the third embodiment in FIG. 5A has a prism 8 on a back surface 2B of a translucent substrate 2 and is formed in a concave shape when viewed from the outside. A case where 2B is covered with a reflective layer 9 made of metal or a white material is shown.

  Also in this embodiment, the light traveling while being totally reflected in the core layer 4 enters the translucent substrate 2 from the core layer 4 at the opening 3a formed in the cladding layer 3, and further, Light is irregularly reflected in various directions within a range of a predetermined divergence angle in the reflective layer 9 provided on the back surface 2B side of the translucent substrate 2.

  Then, the irregularly reflected light re-enters the core layer 4 from the translucent substrate 2, and then the boundary surface between the core layer 4 having a high refractive index and an air clad (air layer) or a surface clad having a low refractive index. Is incident on. At this time, light incident on the boundary surface at a critical angle or less passes through the core layer 4 and exits to the air layer as described above. Therefore, when the surface of the core layer 4 is viewed from directly above, the surface of the core layer 4 facing the opening 3a is partially illuminated compared to the surroundings.

  On the other hand, in the light guide device 1 shown as the second example of the third embodiment in FIG. 5B, the light extraction portion 2a is formed by making the base material 2 itself semi-translucent. Is shown. For example, a semi-translucent resin is obtained by appropriately mixing a large number of inorganic fillers 10 in the translucent synthetic resin used to form the cladding layer 3.

  In this embodiment, when the light traveling while being totally reflected in the core layer 4 is incident from the core layer 4 into the semi-transparent substrate 2 through the opening 3a formed in the cladding layer 3. In addition, since it collides with the inorganic filler within the semi-transparent substrate 2, light can be scattered in various directions within a range of a predetermined divergence angle.

  Of the scattered light, light incident on the interface between the core layer 4 and the air cladding (air layer) or the surface cladding at a critical angle or less is transmitted through the core layer 4 and emitted to the air layer in the same manner as described above. Therefore, the surface of the core layer 4 facing the opening 3a can be partially illuminated.

Next, the manufacturing method of the light guide device of this invention is demonstrated.
FIG. 6 is a process diagram showing the first embodiment of the method of manufacturing the light guide device according to the present invention.

  First, in a 1st process, as shown to (A) of FIG. 6, the light extraction part 2a which irregularly reflects or scatters the light which injected into the surface of the base material 2 is formed. For example, a metal film (aluminum or the like) 6 is formed on the surface of the substrate 2 and is printed thereon with a white dot pattern (first example of the first embodiment). Alternatively, the metal film 6 and a white material are printed in a predetermined pattern on the surface of the substrate 2 (second example of the first embodiment). Alternatively, by inserting and pressing the sheet-like base material 2 against the metal mold on which irregularities are formed (indentation), a convex (or concave on the back surface) prism is transferred to the surface of the base material 2, A half mirror 6A is formed by sputtering a thin metal layer on the surface of the prism 8 formed thereafter. (Third example of the first embodiment).

  The clad layer 3 and the core layer 4 can also be formed of a UV curable resin. In this case, if the base material 2 is formed of a translucent or semi-translucent resin, it becomes possible to irradiate ultraviolet rays from the back side of the base material 2, thereby facilitating the manufacturing process. It becomes possible.

  Next, in the second step, as shown in FIG. 6B, a clad layer 3 having an opening 3a provided at a position corresponding to the light extraction portion 2a is formed. For example, by punching a thin clad material, the clad layer 3 having a predetermined shape in which the opening 3a is formed can be formed. Alternatively, a thermosetting or UV curable liquid synthetic resin is coated in a mold having predetermined irregularities, and cured by applying heat or irradiating ultraviolet rays. And the clad layer 3 provided with the opening part 3a can be formed by die-cutting after resin hardening. Alternatively, the clad layer 3 having the opening 3a can be formed by printing using a screen plate or a metal mask.

  Then, as shown in FIG. 6C, in the third step, the clad layer 3 is laminated on the base material 2 and further formed on the clad layer 3 in advance using another mold. The core layer 4 is stacked. And the laminated body which consists of the said base material 2, the said cladding layer 3, and the said core layer 4 is integrally formed by heating and pressurizing in this state.

  As another process, a clad layer 3 is placed on a base material 2 in a predetermined mold, and a thermosetting liquid synthetic resin is coated on the clad layer 3. By heating and pressurizing in this state, a laminate composed of the base material 2, the clad layer 3 and the core layer 4 may be integrally formed.

  As yet another process, the core layer 4 is integrated on the cladding layer 3 by coating a liquid UV curable resin instead of a thermosetting liquid synthetic resin and curing it by irradiating with ultraviolet rays. You may make it form in. In the method using ultraviolet irradiation, since the UV curable resin is cured relatively quickly, the speed of the light guide device manufacturing process (process speed) can be increased.

  In particular, the half mirror 6A in which a metal is formed as a thin film on the surface of the prism 8 functions as a reflection layer that returns light (light from the light source 5) propagating through the core layer 4 to the core layer 4 side. The light incident from the back surface 2B side of the substrate 2 can be transmitted. For this reason, since it becomes possible to irradiate ultraviolet rays not only from the front surface 2A of the base material 2 but also from the back surface 2B side, the degree of freedom of the manufacturing process can be increased and the core layer 4 can be cured efficiently. Is possible.

  FIG. 7 is a process diagram showing a second embodiment of the method of manufacturing the light guide device according to the present invention. The manufacturing method here is a process diagram for manufacturing the light guide device (see FIG. 5A) shown in the first example of the third embodiment.

  In the method of manufacturing the light guide device showing the second embodiment, first, the light extraction part 2a that irregularly reflects or scatters the incident light on the surface of the resin base material 2 having translucency or semi-translucency. Form.

  Here, a resin sheet having translucency such as a PET sheet is used as the substrate 2. In the steps shown in FIGS. 7A and 7B, the base material 2 is pressed against the first mold 31 on which the convex portions 31a forming the prism are formed and pressed, so that the back surface 2B of the base material 2 is applied. The light extraction part 2a composed of a plurality of prisms 8 is transferred. The prism 8 is formed in a concave shape with respect to the back surface 2B of the substrate 2.

  Next, in the step shown in FIG. 7C, a liquid UV curable resin for the clad layer 3 is coated in the concave portion 32a of the second mold 32, and the surface 2A of the base material 2 is directed downwardly thereon. Install in a state facing toward. Next, ultraviolet (UV) is irradiated from above the substrate 2 to cure the liquid UV curable resin in the first mold 31. Then, when the mold is removed after curing, the clad layer 3 having the opening 3a on the substrate 2 is obtained. In addition, since the base material 2 installed on the upper part of the clad layer 3 has translucency, it can transmit ultraviolet rays.

  Next, in the step shown in FIG. 7D, the core layer 4 is formed using the third mold 33. Also in this case, the core layer 4 having a predetermined shape is formed by coating the liquid UV curable resin for the core layer 4 in the recess of the third mold 33 and irradiating with ultraviolet rays (UV). Note that the step in FIG. 7D may be performed before the steps in FIGS. 7A to 7C.

  In the step shown in FIG. 7E, the top of the base material 2 having the cladding layer 3 is turned upside down with respect to FIG. Then, the core layer 4 formed in the step of FIG. 7D is laminated on the clad layer 3, and hot-pressed in this state. Thereby, the laminated body which consists of the base material 2, the clad layer 3, and the core layer 4 can be formed integrally.

  Instead of the step of FIG. 7D, a liquid UV curable resin is coated on the clad layer 3 in the step of FIG. 7E, and the UV curable resin is cured by irradiating ultraviolet rays. The core layer 4 may be formed by the above, and in this way, it is possible to integrally form a laminate including the base material 2, the cladding layer 3, and the core layer 4. In this method, since the base material 2 has translucency, it is possible to efficiently irradiate the base material 2 through the base material 2 not only from above but also from below, resulting in manufacturing. Time can be greatly reduced.

  7F, the reflective layer 9 is formed on the back surface 2B of the substrate 2 by using, for example, a sputtering method.

  Thus, when the reflective layer 9 is formed on the back surface 2B of the substrate 2 in the last step (FIG. 7F), the irradiation of ultraviolet rays in the previous step can be performed efficiently.

The perspective view which shows the basic composition of the light guide device as embodiment of this invention, 1 is an exploded perspective view of FIG. 1A and 1B show a first embodiment of a light extraction unit, in which FIG. 1A is a cross-sectional view of a light guide device showing a first example of the first embodiment, and FIG. 1B is a first embodiment of the first embodiment; Sectional drawing of the light guide device which shows 2 examples, (C) is sectional drawing of the light guide device which shows the 3rd example of 1st Embodiment, The 2nd Embodiment of the light extraction part is shown, (A) is sectional drawing of the light guide apparatus which shows the 1st example of 2nd Embodiment, (B) is 2nd Embodiment of 2nd Embodiment. Sectional drawing of the light guide device which shows 2 examples, (C) is a perspective view of the light guide device which shows the 3rd example of 2nd Embodiment, FIGS. 3A and 3B show a third embodiment of a light extraction unit, FIG. 3A is a cross-sectional view of a light guide device showing a first example of the third embodiment, and FIG. 3B is a third embodiment of the third embodiment. Sectional drawing of the light guide device which shows two examples, Process drawing which shows 1st Embodiment of the manufacturing method of the light guide device of this invention, Process drawing which shows 2nd Embodiment of the manufacturing method of the light-guide device which concerns on this invention,

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light guide device 1A Laminate body 2 Base material 2A Front surface 2B Back surface 2a Light extraction part 3 Cladding layer 3a Opening part 4 Core layer 5 Light source 6 Metal film 6A Half mirror 7 Dot pattern 8 Prism (fine convex part)
9 Reflective layer 10 Inorganic filler

Claims (13)

A laminate comprising a base material, a clad layer laminated on the base material, and a core layer laminated on the clad layer, and light incident on the core layer travels inside the core layer In the light guide device that is emitted toward the outside from the surface of the core layer,
An opening is formed in the cladding layer, a part of the synthetic resin forming the core layer enters the opening,
A light extraction portion that reflects light incident on the base material facing at least the opening to a specific direction or diffusely reflects or scatters within a predetermined spread angle is formed on the base material .
In the light extraction part, the light incident on the base material is directed at an angle emitted from the surface of the core layer.   The light guide device according to claim 1, wherein the light extraction portion is formed on a surface of the base material that is in contact with the clad layer or a back surface on the opposite side. 2. The light guide device according to claim 1, wherein in the light extraction portion, a convex prism is formed on a surface of the base material in contact with the clad layer, and a reflective layer is formed on the surface including the prism. Light guiding device according to claim 1, wherein said substrate has a light-transmitting property. The light guide device according to claim 4, wherein in the light extraction portion, a concave prism is formed on the back surface of the base material, and a reflective layer is formed on the back surface including the prism.   The light guide device according to claim 5, wherein the reflective layer is formed of a half mirror. Wherein the substrate, the internal mix inorganic filler is formed from a semi-translucent synthetic resin obtained, according to claim 1, wherein the substrate is the light extraction portion appearing on the opening is formed Light guide device. A first step of forming a light extraction portion for reflecting, irregularly reflecting, or scattering incident light on the surface of the substrate;
A second step of forming a clad layer provided with an opening corresponding to the light extraction portion;
Forming a core layer for propagating the light,
After laminating the clad layer on the base material and further laminating the core layer on the clad layer, the base material, the clad layer and the core layer are integrated by heating and pressing. A third step of allowing a part of the resin forming the core layer to enter the opening ,
A method of manufacturing a light guide device, comprising: Instead of the third step, a clad layer is laminated on the base material in a predetermined mold, and a liquid thermosetting resin is coated on the clad layer, and then heated and heated. The step of integrating the base layer, the clad layer, and the core layer formed of the thermosetting resin by pressing, and allowing a part of the thermosetting resin to enter the opening. A method for manufacturing the light guide device according to claim 8 . Instead of the third step, a clad layer is laminated on the base material in a predetermined mold, and a liquid UV curable resin is coated on the clad layer and then irradiated with ultraviolet rays. And a step of integrating the base layer, the clad layer, and the core layer formed of the UV curable resin, and allowing a part of the UV curable resin to enter the opening. A method for manufacturing the light guide device according to claim 8 . A step (1) of forming a light extraction portion that transfers a plurality of prisms having a predetermined shape to the back surface of a base material made of a resin sheet having translucency to reflect, diffusely reflect, or scatter light incident on the base material ; ,
Forming a cladding layer having an opening that faces the radiation exit part of light to be emitted to the outside from the core layer be one totally reflected toward the core layer on a surface of the substrate (2) When,
Forming the core layer for propagating light on the cladding layer, and allowing a part of the resin forming the core layer to enter the opening (3),
A method of manufacturing a light guide device, comprising a step of forming a reflective layer on a back surface of the base material. In the step (2), a predetermined mold is coated with a liquid UV curable resin, and the surface of the base material is set, and the UV curable resin is cured by irradiating ultraviolet rays. method for producing a subsequent demolding light guiding device according to claim 11, wherein said clad layer is formed with the opening by. In the step (3), a liquid UV curable resin is coated on the clad layer and the UV curable resin is cured by irradiating ultraviolet rays to form the core layer. 11. A method for producing a light guide device according to 11 .

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