JP6636727B2 - Lighting equipment - Google Patents

Description

The present invention relates to a lighting device in which a light source and a light transmitting body are combined.

  2. Description of the Related Art A lighting device that is used for a lighting application, a decoration application, or the like and that combines a light emitting element and a light transmitter that emits side light is known. As such a lighting device, the one described in Patent Document 1 is known.

In the lighting device (linear luminous body) described in Patent Document 1, a light emitting diode is disposed on an end face of a light transmission tube in which a core in which diffused particles are dispersed is injected into a clad, and light incident from the light emitting diode is transmitted light. It is configured to emit light from the side of the tube.

That is, it can be said that the lighting device described in Patent Literature 1 is configured to obtain side emission by diffusing the light incident on the light transmission tube by the diffusing particles dispersed in the core.

Patent Document 2 discloses an optical fiber configured to obtain side emission by dispersing diffusion particles (zinc oxide particles) in a clad, and a light emitting device in which a light source is combined with the optical fiber.

In various lighting devices, the magnitude of the light amount is one of the important parameters indicating the performance of the lighting device, and various measures are taken to increase the light amount. The same applies to a lighting device using an optical transmitter that emits light from the side, and various studies have been made to increase the amount of light emitted from the side of the optical transmitter.

  As a method of increasing the amount of light in a lighting device using an optical transmitter that emits side light, the core or the concentration of diffused particles contained in the clad is increased, the amount of light of the light source itself is increased, and the core diameter at the incident end face of the optical transmitter is increased. Although such a method is known, the following problem exists.

The method of increasing the concentration of the diffused particles increases the amount of light near the light source while decreasing the amount of light away from the light source. Therefore, it is difficult to increase the amount of light in the entire optical transmission body. In order to prevent this, it is necessary to take measures such as increasing the concentration distribution of the scatterer (diffusion particles) toward the tip end side, as in the light scattering portion constituting the light irradiation fiber described in Patent Document 3. A complicated operation of controlling the concentration distribution occurs in the manufacturing process.

In order to increase the light amount of the light source itself, it is possible to increase the light amount of the entire optical transmission body without special measures on the optical transmission body side.However, since the power consumption tends to increase with the increase in the light amount, recently, This is not always the preferred method in the situation where energy saving intentions are increasing.

The method of increasing the core diameter at the incident end face of the optical transmission body described in Patent Document 4 is capable of injecting more light into the optical transmission body while maintaining the light amount of the light source itself, so that the light can be transmitted without increasing power consumption. Although an increase in the amount of light in the entire transmitter can be expected, the cladding diameter of the incident end face also increases, so it is necessary to secure an installation space for the optical transmitter in the equipment to be mounted. Tends to decrease.

JP 2000-131529 A JP 2006-317844 A JP 2008-216907 A JP-A-9-113742

It is an object of the present invention to provide a lighting device that can obtain an effect of increasing the amount of light in the entire light transmitting body by a simple operation without changing the outer dimensions of the light transmitting body that emits side light.

The inventor of the present invention has studied the structure of the light transmitting body that emits side light, and as a result, has noticed that the surface area of the core at the incident end face affects the light amount of the light transmitting body. It has been found that the above problem can be solved by increasing the core surface area without increasing the outer diameter of the clad.

The lighting device according to the present invention includes a light transmitting element having a core / structure in which a core is surrounded by a clad and having a function of emitting light from a side, and a light emitting element for emitting light to an incident end of the light transmitting element. Wherein the light transmitting body is configured such that, at the incident end, without increasing the outer diameter of the cladding, the surface area of the core cuts the light transmitting body perpendicularly to its length direction. It is characterized in that it is larger than the cross-sectional area of the core obtained.

Further, in the lighting device of the present invention, the surface area of the core is formed such that the entirety of the core is formed substantially concave at the incident end, so that the optical transmission body is cut perpendicularly to the length direction thereof. It is characterized in that it is larger than the cross-sectional area of the core obtained.

Further, in the illumination device of the present invention, the light emitting element, characterized in that it is inserted into the core formed in a substantially concave shape of the incident end portion.

Further, in the illumination device of the present invention, it is preferable that the substantially concave core is formed by cutting the incident end of the optical transmission body into a V-shape.

Further, in the lighting device of the present invention, it is preferable that a first reflection member that reflects light incident on the light transmitting body from the light emitting element be provided at an emission end of the light transmitting body.

Further, in the lighting device of the present invention, it is preferable that a second reflecting member is provided near the light emitting element.

The lighting device of the present invention has the following excellent effects.

-An increase in the amount of light in the entire optical transmission body can be obtained.

・ Since the outer dimensions of the optical transmission body do not increase, it can be easily mounted on equipment having a limited mounting space.

-Even after the optical transmission body is created, the light amount can be increased by performing simple additional processing on the optical transmission body. For this reason, the present invention can be applied to an existing optical transmission body, and can be implemented without changing the existing manufacturing method of the optical transmission body.

Further, in a more preferred embodiment of the lighting device of the present invention, the following effects are also obtained.

-The volume at the joint between the light transmitter and the light emitting element can be reduced, which leads to further downsizing of the lighting device.

3 is a basic structure of the lighting device of the present invention. It is an example of the shape of the entrance end in the present invention. This is an example in which a reflecting member is added to the lighting device of the present invention. It is an example of an embodiment of the present invention. It is a schematic diagram of the light quantity measuring method of the present invention. 6 is a measurement result of a light amount in each embodiment of the present invention.

Hereinafter, an embodiment of the lighting device of the present invention will be described with reference to FIG. In FIG. 1, 1 is an optical transmitter, 2 is a cladding of the optical transmitter, 3 is a core of the optical transmitter, 4 is an incident end of the optical transmitter, 5 is an emitting end of the optical transmitter, and 6 is a light emitting element. It is.
The optical transmission body 1 used in the present invention has a core / cladding structure in which a core 3 is surrounded by a cladding 2 and has a function of emitting side light.

A feature of the present invention is that the surface area of the core 3 is perpendicular to the longitudinal direction of the optical transmission body 1 without increasing the outer diameter of the cladding 2 at the incident end 4 of the optical transmission body 1. Is larger than the cross-sectional area (hereinafter, referred to as a standard cross-sectional area) of the core 3 obtained when the core 3 is cut.

The amount of light that can be received by the optical transmitter 1 from the light emitting element 6 varies depending on the surface area of the core 3 at the incident end 4, so that the surface area of the core 3 is made larger than the standard cross-sectional area, that is, the incident end 4. In this case, by increasing the surface area of the core 3 to be larger than the surface area when the surface of the core 3 is formed in a plane perpendicular to the longitudinal direction of the optical transmission body 1, the amount of light that can be received by the optical transmission body 1 from the light emitting element 6 increases. The amount of light increases throughout the body 1.

  In addition, by increasing the surface area of the core 3 without increasing the outer diameter of the cladding 2, the light amount can be increased while maintaining the outer dimensions of the optical transmission body 1. Even when the mounting space is limited, mounting can be easily performed, and the number of situations where the optical transmitter 1 can be used can be increased.

As the core 3 used in the present invention, a material conventionally used as a core of an optical transmitter that emits side light may be appropriately selected and used. Specifically, a resin material such as a silicone resin, an epoxy resin, and polyurethane is used.

As the clad 2 used in the present invention, a material having a lower refractive index than that of the core 3 may be appropriately selected and used from materials conventionally used as clads of an optical transmitter that emits side light. Specific examples include resin materials such as polyethylene, polypropylene, polyester, PFA (tetrafluoroethylene / perfluoroalkylvinyl ether copolymer), and FEP (tetrafluoroethylene / hexafluoropropylene copolymer).

  The light transmitting body 1 used in the present invention may be a core or clad 2 having a side surface light emitting function by containing diffusing particles or using other known methods.

A particularly suitable method for increasing the surface area of the core 3 beyond the standard cross-sectional area without increasing the outer diameter of the clad 2 is to form the entire core 3 at the incident end 4 into a substantially concave shape.
By forming the entire core 3 in a substantially concave shape, the surface area of the core 3 can be increased while the dimensions of the clad 2 remain unchanged.

In addition, forming the core 3 in a substantially concave shape is a preferable method in that the light emitting element 6 can be inserted into the core 3 formed in a substantially concave shape.
By inserting the light emitting element 6 into the core 3 formed in a substantially concave shape, it is possible to reduce the volume at the joint portion between the light transmitting element 1 and the light emitting element 6, which leads to further downsizing of the lighting device.
Further, light emitted from the side peripheral surface of the light emitting element 6 also enters the core 3, which can contribute to an increase in the amount of light of the optical transmission body 1.

  Specific examples of the substantially concave shape include (a) a V shape, (b) a spherical shape, and (c) a conical shape shown in FIG. In the present invention, a V-shape is particularly preferable.

The core 3 and the clad 2 used in the present invention often use various resin materials as described above.
Since such a resin material can be easily cut, cutting the end of the optical transmission body 1 into a V-shape allows the core 3 to be formed in a substantially concave shape with a small amount of trouble.

In the present invention, as shown in FIG. 3, a first reflecting member 7 that reflects light transmitted from the light emitting element 6 into the optical transmission body 1 is provided at the emission end portion 5 of the optical transmission body 1. Is preferably provided.
By providing the reflection member 7 at the emission end 5 of the optical transmission body 1, the light reaching the emission end 5 is reflected and transmitted through the optical transmission body 1 again. Can be increased more.

  As the reflection member 7, a material having a high surface reflectance such as a metal foil or a white resin plate may be appropriately selected and used.

In addition, in the present invention, as shown in FIG. 3, it is preferable to cover the vicinity of the light emitting element 6 with the second reflection member 8.
By covering the vicinity of the light emitting element 6 with the reflecting member 8, the light that has not entered the core 3 from the light emitting element 6 and the light that has entered do not satisfy the condition of total reflection at the interface between the core 3 and the clad 2. Since the light leaked to the outside of the optical transmission body 1 can be reflected and a part of the light can enter the core 3, the light amount of the optical transmission body 1 can be further increased.

  The range in the vicinity of the light emitting element 6 indicates a range in which the effect of increasing the light amount of the optical transmission body 1 can be obtained by the presence of the second reflection member 8 at that location.

  As a method of providing the second reflection member 8, as shown in FIG. 3, usually, the second reflection member 8 may be provided so as to cover the surface of the clad 2 existing near the incident end 4, but is not limited to this method. However, it is possible to make a change such as providing the light transmission element 1 directly on the light emitting element 6 in a range where the light amount increasing effect of the optical transmission body 1 can be obtained.

  As with the first reflecting member 7, a material having a high surface reflectance may be appropriately selected and used as the second reflecting member 8. However, in consideration of covering the surface of the clad 2, a metal foil is used. For example, a flexible member such as a metal pipe formed in the same shape as the outer shape of the clad 2 is preferable.

Hereinafter, a lighting device according to a first embodiment of the present invention will be described with reference to FIG.

As a material of the clad 2, a PFA tube having an outer diameter of 3.5 mm and an inner diameter of 3 mm was used.

As a material of the core 3, a polyurethane containing silica particles uniformly as diffusion particles was used.

The PFA tube serving as the clad 2 was filled with polyurethane serving as the core 3, and the polyurethane was cured to complete the light transmitting body 1 which emits light from the side, and was cut into a length of 550 mm. At this stage, the input end 4 and the output end 5 of the optical transmission body were formed in a flat shape by cutting the optical transmission body 1 perpendicularly to the length direction when cutting the optical transmission body 1. That is, the surface area of the core 3 at the incident end 4 has a standard sectional area.

The surface area of the core 3 was made larger than the standard cross-sectional area without increasing the outer diameter of the clad 2 by forming the core 3 in a substantially concave shape at the incident end 4 of the optical transmission body 1.

The V-shape shown in FIG. 2A was selected as the substantially concave shape. The incident end 4 of the optical transmission body 1 cut into a predetermined length and formed flat as described above was cut into a V-shape with a blade to form a V-shaped recess. The size of the concave portion was such that the V-shaped depth was 2 mm and the apex of the V-shaped portion was located on the central axis of the optical transmission body 1.

As the light-emitting element 6, a bullet-shaped LED having a diameter of 3 mm was used. A power cable 9 is connected to the LED 6, as shown in FIG. The material and the outer diameter of the protective coating of the power cable 9 were the same PFA as that of the cladding 2 and φ3.5 mm.

After the light emitting portion of the LED 6 is inserted into the concave portion formed in the optical transmission body 1, the length is sufficient to cover from the outer periphery of the cladding 2 near the incident end 4 to the outer periphery of the protective coating end of the power cable 9. As shown in FIG. 4, the protective tube 10 having the above was placed near the incident end 4 of the optical transmission body 1 and joined to the clad 2 and the power cable 9 by heat fusion.

As the protective tube 10, a PFA tube having an inner diameter of 3.5 mm and a thickness of 0.3 mm was used. Since the same material is used for the protective coating of the cladding 2 and the power cable 9, joining by heat fusion can be performed reliably.

As described above, the lighting device according to the first embodiment of the present invention was completed.

The light amount of the completed lighting device of the first embodiment was compared with that of the conventional lighting device.
A conventional lighting device prepared under the same conditions as the completed lighting device except that the incident end is formed flat and the LED tip is in contact with the incident end is prepared. did.

  FIG. 5 shows a method for measuring the amount of light. A block provided with an insertion hole through which the optical transmission body 1 can be inserted is prepared, and the light receiving element 11 of the light meter is provided in the block. The block is moved from the input end 4 to the output end 5, and a change in the amount of light accompanying a change in the distance from the input end 4 is measured. The measurement range was 40 mm to 500 mm from the incident end 4.

FIG. 6 shows the measurement result of the light amount of the lighting device of the first embodiment as a ratio with respect to the case where the light amount in the conventional lighting device is set to 100% over the entire length of the optical transmission body.

The amount of light in the first embodiment is approximately 40% at the maximum in the vicinity of the entrance end 4 of the optical transmission body 1 and approximately 15% in the vicinity of the exit end 5, which is larger than that of the conventional lighting device. The effect of increasing the amount of light was confirmed.
In addition, the reason why the amount of light is larger in the vicinity of the incident end 4 than in the vicinity of the output end 5 is that the diffused particles are uniformly dispersed in the core 3, and as a result, the light incident at the incident end 4 is This is because the light in the optical transmitter 1 is attenuated toward the emission end 5 while being diffused (side emission) and consumed toward the emission end 5 near the incidence end 4. This is a tendency generally observed in an optical transmitter that emits side light.

  Further, the light amounts of the lighting devices of the second to fourth embodiments to which one or both of the first reflecting member 7 and the second reflecting member 8 were added were also measured.

The specifications of the lighting devices of the second to fourth embodiments are as follows.

-2nd Example: The 1st reflection member 7 was added to 1st Example.
Third embodiment: A second reflecting member 8 is added to the first embodiment.
Fourth embodiment: Both the first reflecting member 7 and the second reflecting member 8 are added to the first embodiment.

  An aluminum foil tape having a thickness of 0.05 mm was used for the first reflecting member 7, and provided so as to cover the emission end 5 of the optical transmission body 1.

  As the second reflecting member 8, the same aluminum foil tape as that of the first reflecting member 7 is used. As shown in FIG. 3, the surface of the clad 2 near the incident end 4 is covered with the aluminum foil tape. After the LED 6 is hidden, a protection tube 10 is provided.

  FIG. 6 shows the measurement results of the light amounts of the lighting devices of the second to fourth embodiments.

In the second embodiment in which only the first reflecting member 7 is provided, a maximum of about 40% near the entrance end 4 of the optical transmission body 1 and about 28% near the exit end 5 of the optical transmission body 1, the conventional lighting device The light quantity increased more.

The reason why the light quantity increase near the emission end 5 is higher than that near the incidence end 4 is that the light reflected by the first reflecting member 7 is diffused near the emission end 5 while being incident on the incidence end 4. It can be said that the reflected light was consumed mainly for the side emission in the vicinity of the emission end portion 5 because of going to the side.

In the third embodiment in which only the second reflecting member 8 is provided, a maximum of about 43% near the input end 4 of the optical transmission body 1 and about 25% near the output end 5 of the conventional optical device The light quantity increased more.

  Since the second reflecting member 8 is for improving the light entering from the LED 6 to the incident end 4, it can be said that the second reflecting member 8 has mainly contributed to an increase in the amount of light near the incident end 4.

  In the fourth embodiment in which both the first reflection member 7 and the second reflection member 8 are provided, about 45% is provided near the entrance end 4 and about 30% is provided near the exit end 5, and the conventional illumination is used. The amount of light was increased as compared with the device, and the effect of increasing the amount of light due to the synergy of the two reflecting members could be obtained.

INDUSTRIAL APPLICABILITY The present invention can be used for various illumination male devices using a light transmitter that emits side light, such as illumination applications and decorative applications.
In addition, the method of increasing the amount of light by forming the incident end portion of the optical transmission body in a substantially concave shape is effective even when the type of the optical transmission body that emits side light is changed or when the light emitting element is changed to another light source. Available.
Further, within the scope of the technical idea of the present invention, it is also possible to use in combination with another light amount increasing method in the side-light emitting optical transmitter.

DESCRIPTION OF SYMBOLS 1 Optical transmission body 2 Cladding 3 Core 4 Incident end 5 Outgoing end 6 Light emitting element 7 First reflecting member 8 Second reflecting member 9 Power cable 10 Protective tube 11 Light receiving element

Claims (4)

An optical transmission body having a core / clad structure in which the periphery of the core is surrounded by a clad, and having a function of emitting side light;
A light emitting element configured to make light incident on an incident end of the light transmitting body,
In the light transmitting body, the core is formed in a substantially concave shape without having a cross section obtained when the core is cut perpendicular to the length direction of the light transmitting body at the incident end. By doing so, without increasing the outer diameter of the cladding, the surface area of the core is larger than the cross-sectional area of the core obtained when the optical transmission body is cut perpendicularly to the length direction. ,
The light-emitting element is inserted into the core formed in a substantially concave shape at the incident end,
In a cross section perpendicular to the length direction of the optical transmission body, the core has, on both sides of a central axis of the optical transmission body, a surface for receiving light emitted from a side peripheral surface of the light emitting element. A lighting device characterized by the above-mentioned. Core formed in the symbolic concave, characterized in that it is formed by cutting the entering end of the light transmitting body in a V-shape, the illumination device according to claim 1. At the exit end of the optical transmission body, and reflects the light incident on the optical transmission member from the light emitting element, characterized in that the first reflecting member is provided, according to claim 1 or 2 Lighting equipment. The lighting device according to any one of claims 1 to 3, wherein a second reflecting member is provided near the light emitting element.

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