JP4668153B2 - Lighting equipment - Google Patents

Description

  The present invention relates to an illuminating device such as an interior lamp of an automobile, and more particularly to an illuminating device suitable for application to an illuminating device that illuminates a wide area using a small light source as a light source.

2. Description of the Related Art In recent years, an illuminating device using a small light source such as an LED as a light source has been proposed as an illuminating device for illuminating a relatively wide area such as a car interior light. For example, in Patent Document 1, an LED is provided as a light source at the end of a light transmission tube for linear light emission, light emitted from the LED is guided into the tube from the end of the light transmission tube, and the light is transmitted through the light transmission tube. There has been proposed a configuration in which light is emitted as diffused light from the side surface (circumferential surface) of the tube when guided inside. By combining a plurality of such light transmission tubes, it is possible to configure an illuminating device that can illuminate a relatively wide area such as a passenger compartment while using a small light source.
JP 11-66929 A

  In the light transmission tube as in Patent Document 1, when light is incident from one end of the tube, the light guided through the tube is emitted from the side surface, so the amount of emitted light is reduced, and a wide area is illuminated uniformly. It becomes difficult to do. Therefore, in Patent Document 1, LEDs are arranged at both ends of the light transmission tube, and light is incident from both ends of the light transmission tube to equalize the light amount in the linear direction. Double the number of LEDs is required, which increases the cost. In addition, a lighting device that combines a linear light emitting pattern and a planar light emitting pattern may be required due to the requirement of the light emitting pattern of the lighting device. In this case, light for obtaining the linear light emitting pattern is required. The transmission tube and the light block for obtaining the planar light emission pattern are combined to emit light from each. However, it is necessary to arrange the LED in each of the light transmission tube and the light block to make the light incident. Yes, it becomes a factor of high cost.

  An object of the present invention is to achieve a uniform light amount distribution in a linear light guide for obtaining a linear light emission pattern, and to reduce the cost of an illumination device that combines a linear light emission pattern and a planar light emission pattern. An illumination device is provided.

  The present invention includes a linear first light guide that receives light from one end surface, and a second guide that is formed by receiving light emitted from the other end of the first light guide. An illumination device configured to internally reflect incident light and to emit a part of light from the surface as illumination light. At least two first light guides are provided, and the second light guide directs a part of light incident from one first light guide toward the other end surface of the other first light guide. It is the structure which can radiate | emit.

  According to the illumination device of the present invention, when light emitted from the light source is incident on one end face of the first light guide, the light passes through the first light guide and reaches the second light guide. Light is guided, and illumination can be performed by emitting light from the respective surfaces of the first light guide and the second light guide at the same time. The illumination with the planar second light guide can be performed only by providing the number of light sources corresponding to the first light guide, and the cost of the apparatus can be reduced. In addition, a part of the light incident on the second light guide from the other end surface of one of the first light guides is incident on the other end surface of the other first light guide. The light quantity distribution in the length direction in the light body is made uniform, and illumination with uniform brightness in the length direction becomes possible.

  As a preferred embodiment of the present invention, the second light guide is formed in a semicircular arc shape having two end faces or substantially U-shaped, and two first light guides are formed on the two end faces of the second light guide. The other end faces of the light guide are arranged to face each other. The linear first light guide and the semicircular arc second light guide can obtain a U-shaped light distribution pattern having a long linear portion and a wide tip portion, as a whole. The amount of light at the linear portion can be made uniform.

  In the present invention, the second light guide has an incident portion recessed in a cylindrical shape on the end face where the other end face of the first light guide is opposed, and is incident on the second light guide. The diffused light can be diffused to make the light emitted from the surface of the second light guide uniform, and can be emitted with an appropriate amount of light to the other end surface of the first light guide. Moreover, the incident part can raise the said diffusion effect because the surface is roughened.

  In the present invention, the first light guide has a light diffusion tube on the surface, the second light guide has a light diffusion step formed on the surface, and the first light guide and the second light guide are formed. Light emitted from each surface of the light guide can be diffused to increase the uniformity of the brightness of the illumination.

  Next, Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is an external perspective view of an embodiment in which the present invention is applied to a room lamp (interior light) RL disposed on a ceiling RF in a vehicle interior of an automobile, and FIG. 2 is a partially exploded view thereof. 3 and 4 are cross-sectional views taken along the lines AA and BB in FIG. Here, in the following description, the terms “front”, “rear”, and “upper” and “lower” are based on the front, rear, and top and bottom of the automobile. The room lamp RL of the first embodiment includes a lamp base 1 that is formed of a resin or the like and is attached to a ceiling RF in a vehicle interior of a vehicle by screws or the like that are not shown in the drawing. The lamp is assembled.

  The lamp base 1 has a required length from the front to the rear of the ceiling RF in the passenger compartment, and is usually a length from the position between the driver's seat and the passenger's seat to a substantially intermediate position in the front-rear direction of the ceiling RF. It is formed in a shape that is close to a rectangle that is extended. The intermediate portion 12 in the width direction (short side direction) of the lamp base 1 is formed so that a region extending from the front end edge 10 to the vicinity of the rear end portion 11 protrudes downward in a rectangular convex shape. The both sides 13 of a pair of elongated regions sandwiching 12 in the width direction and the region of the rear end 11 having a shape close to a square on the rear end side of the intermediate portion 12 are formed flat. And the lower surface of the rear-end part 11 is comprised as a light reflection surface. A manually operable lamp switch 7 is disposed on a part of the surface of the intermediate portion 12. Further, each side 13 is covered with a translucent cover 2 from below, and similarly, the rear end 11 is covered with a translucent lens 3 from below. It is supported by the base 1.

  The cover 2 is formed of a transparent resin, and is formed as a pair of long and narrow plates having a cross-section with a passage through the whole or part of which is formed with an L-shaped cross section. The lamp base 1 is detachably attached so as to cover the lower region and the side region of the side portions 13. The lens 3 is formed of a light-transmitting resin, and is formed in a nearly square shallow plate shape in which required lens steps are formed so as to obtain required light diffusion characteristics. The lens 3 is detachably attached to the lamp base 1 so as to cover a lower region and a side region of the rear end portion 11 by fixing means not shown in the drawing.

  The light source 4 and the first light guide 5 are fixedly supported on the lower surfaces of the pair of both side portions 13 of the lamp base 1, and the second light guide 6 is fixedly supported on the lower surface of the rear end portion 11. Has been. As shown in a perspective view of the state excluding the lamp base 1 in FIG. 5, the light source 4 is composed of a small light source, here, one LED 41, and each LED 41 is a front end of the side portion 13. It is supported at the side position. The LED 41 can be of any emission color, but here a blue LED with a discrete configuration is used. These LEDs 41 are supported on the lamp base 1 by a fixed plate 42, and each LED 41 has its light output optical axis directed rearward. The LEDs 41 are electrically connected to a power source via the lamp switch 7 and a drive circuit unit not shown in the drawing.

  The first light guide 5 is composed of two linear (straight) light guides, and the second light guide 6 is a single light guide having a planar shape, here a semicircular arc surface. Consists of the body. Here, the first light guide 5 is constituted by a cylindrical optical fiber type light guide having a diameter of about 10 mm. This optical fiber type light guide has a cylindrical core 51 formed of a resin having translucency, and a clad made of a light diffusing milky white light diffusion tube 52 covering the circumferential side surface of the core 51. It consists of The two first light guides 5 are respectively disposed on both side portions 12 of the lamp base 1 and supported by the lamp base 1 by clamps 53 in the vicinity of both ends in the length direction. Each first end face 5 a of the first light guide 5 is disposed to face the LED 41, and the other end face 5 b is disposed to face the second light guide 6.

  The second light guide 6 has a plate thickness somewhat thicker than the diameter of the first light guide 5 and has a width of about 3 to 4 times the diameter of the first light guide 5. The resin is formed in a semicircular arc shape, and both end surfaces 6a are arranged on substantially the same surface, and the other end surfaces 5b of the two first light guides 5 are arranged opposite to the both end surfaces 6a. Has been. In addition, on both end surfaces 6 a of the second light guide 6, incident portions 61 each formed of a semicylindrical recess having a required diameter are provided at locations where the other end surface 5 b of the first light guide 5 is opposed. Is formed. In the first embodiment, the incident portion 61 is provided at a position offset outward in the width direction of the both end faces 6a, so that the axial core of the second light guide 5 and the cylindrical core of the incident portion 61 coincide. ing. The cylindrical diameter of the incident portion 61 is substantially equal to the diameter of the first light guide 5, and the other end surface 5 b of the first light guide 5 and the incident portion 61 are at an appropriate interval, for example, about 1 to 5 mm. They are spaced apart. Although the upper surface 6b and the lower surface 6c of the second light guide 6 remain transparent, the both end surfaces 6a, the outer peripheral surface 6d, and the inner peripheral surface 6e on which the light incident portion 61 is formed are subjected to texture processing or the like. Roughening is applied. In addition, a large number of conical or pyramidal minute concave portions (dots) 62 projecting toward the inside are provided as light diffusion steps almost over the entire upper surface 6b. Since the configuration of the minute recess 62 is a known configuration, detailed description thereof is omitted here. Further, support pieces 63 for fixing and supporting the second light guide 6 to the lamp base 1 with screws not shown are integrally formed at two locations along the outer peripheral surface 6d so as to protrude in the radial direction.

  According to the above configuration, when the occupant turns on the lamp switch 7, power is supplied to the two LEDs 41, these LEDs 41 emit light, and the emitted light is emitted from the one end face 5 a to the first light guide 5. Incident inside. FIG. 6A shows the optical path for one LED 41 (the upper LED in the figure), and this is the same for both of the two first light guides 5. The light guided through the first light guide 5 is guided in the length direction by internal reflection at the core 51, emitted from the other end surface 5 b, and provided on the end surface 6 a of the second light guide 6. Then, the light enters from the incident part 61 into the second light guide 6. Further, in the first light guide 5, when light is internally reflected on the peripheral surface of the core 51, the light is diffused in the light diffusion tube 52 that is in close contact with the peripheral surface. A part of the light passes through the light diffusion tube 52 and is emitted from the surface to the outside. Therefore, in the first light guide 5, light is guided in the length direction, and at the same time, the circumferential surface is a light emitting surface over almost the entire length of the second light guide 5. Therefore, the first light guide 5 becomes a linear light emitter, and the light emitted in this way is reflected by the lower surface of the lamp base 1 and then passes through the cover 2 as shown in FIG. Or the emitted direct light permeate | transmits the cover 2 and is radiate | emitted outside, and will light the vehicle interior.

  On the other hand, the light guided to the second light guide 6 is guided along the arc shape while being sequentially internally reflected by the arc-shaped outer peripheral surface 6d and the inner peripheral surface 6e of the second light guide 6. Is done. In the first embodiment, a semi-cylindrical incident portion 61 is provided on the end surface 6 a of the second light guide 6, and light emitted from the other end surface 5 b of the first light guide 5 is incident on the incident portion 61. Therefore, the light is diffused in the width direction in the incident portion 61, and the light is guided toward a wide range of the outer peripheral surface 6d and the inner peripheral surface 6e, so that almost the entire inner region of the second light guide 6 is obtained. Light is guided toward the surface and internal reflection is performed. In particular, by forming the incident portion 61 on a rough surface, the diffusibility of light upon incidence increases. A part of the light guided in this way is emitted to the outside from the outer peripheral surface 6d. At the same time, as shown in FIG. 6B, another part of the guided light is reflected by the convex portion when viewed from the inside of the minute concave portion 62 of the upper surface 6b, that is, the second light guide. The light is directed toward the lower surface 6c, passes through the lower surface 6c, and is emitted downward. At this time, since the inner surface reflection on the outer peripheral surface 6d and the inner peripheral surface 6e is repeatedly performed in various directions inside the second light guide 6, the probability that light is reflected in the minute recess 62 is also increased. An extremely large amount of light is emitted from the lower surface 6c. In addition, for the light that is not reflected by the minute recesses 62, the outer peripheral surface 6d and the inner peripheral surface 6e of the second light guide 6 are formed as rough surfaces, and therefore the critical angle when reflected internally by these surfaces. Light that does not satisfy is generated and emitted to the outside. The light emitted from the second light guide 6 passes through the lens 3 and becomes appropriate diffused light by the steps provided in the lens 3. As a result, the amount of light emitted from the second light guide 6 becomes substantially uniform along the arc direction and the width direction of the second light guide 6, and the lens 3 on the rear end side of the room lamp RL. The area becomes a uniform light emitter and illuminates the interior of the vehicle.

  Here, regarding the one first light guide 5, the light of the LED 41 is incident from the one end surface 5 a, and a part of the light is emitted from the peripheral surface as described above when guided inside. Therefore, as schematically shown in FIG. 6 (c1), the amount of light gradually guided along the length direction of the first light guide 5 is reduced, and the length of the room lamp RL is reduced. There is a possibility that the light amount distribution along the vertical direction is biased. This figure shows the light quantity distribution of the forward light when the light of the LED 41 is guided from the left end face 5a to the first light guide 5 shown in FIG. 6B. From the light quantity on the one end face 5a side. In addition, the amount of light on the other end surface 5b side is reduced. However, in the first embodiment, the other end surfaces 5b of the two first light guides 5 are disposed opposite to the opposite end surfaces 6a of the second light guides 6, respectively. As described above, a part of the light guided from one end face 6a1 on the upper side in the drawing to the other end face 6a2 in the second light guide 6 leaks out from the other end face 6a2 and is arranged opposite to this. The incident light is incident on the other end surface 5b of the lower first light guide 5 shown in the figure. The incident light is guided in the first light guide 5 toward the LED 41, and the light guided in the opposite direction is also emitted from the peripheral surface of the first light guide 5. The amount of light gradually decreases along the length direction of the first light guide 5, and the characteristics of returning light shown in FIG. 6C 2 are obtained. Therefore, in the first light guide 5, the forward light incident from the LED 41 and guided in the forward direction is combined with the return light incident from the second light guide 6 and guided in the opposite direction. Illumination with light is performed, and as a result, as shown in FIG. 6 (c3), illumination with a characteristic of a substantially uniform light amount is performed over the entire length of the first light guide 5.

  As described above, in the first embodiment, the two first light guides 5 each linearly formed by the two LEDs 41 are caused to emit light, and the light is passed through the first light guide 5 to form a planar shape. Since the second light guide 6 is caused to emit light, and these are configured as the light emitters of the room lamp RL, the linear light emitter (first light guide 5) and the planar light emitter (only the two LEDs 41). The second light guide 6) can emit light, and the cost of the room lamp RL can be reduced by configuring the LED 41 with a minimum number. The linear first light guide 5 guides light from the LED 41 in the forward direction and guides light emitted from the inside of the planar second light guide 6 in the opposite direction. Since the light is emitted and emitted in a state in which these lights are combined, the light quantity in the length direction of the first light guide 5 can be made uniform. Furthermore, since the light guided by the planar second light guide 6 is emitted to the outside after repeated internal reflection, uniform light emission is possible over the entire second light guide 6. Become. As a result, it is possible to illuminate a relatively wide area such as the passenger compartment with uniform brightness with a small light source such as an LED.

  In the first embodiment, the first linear light guide body and the second planar light guide body are formed, but the number of the first linear light guide bodies is three or more. In any case, an LED may be disposed on one end surface, and the other end surface may be disposed opposite to the planar second light guide so that light can enter and exit. The first light guide may have a rectangular shape or a wave shape (continuous uneven surface) in which the cross section along the light guide direction of the side surface is continuous in addition to the cylinder. Further, the first light guide may be not only a straight line but also an arc or other smooth continuous curve. On the other hand, the second light guide is not limited to the semicircular arc shape of the first embodiment, and the incident light is internally reflected and guided to other places, particularly to other different first light guides. The present invention can be similarly applied as long as the configuration is such.

  The light source in the present invention is not limited to the LEDs described in the embodiments, and may be other light emitting elements such as a small incandescent bulb, EL (electroluminescence), and LD (laser diode). In addition, the present invention is not limited to the room lamps described in the embodiments, and particularly in a lighting device using a small light source, if the lighting device has a light emission pattern in which linear and planar light emission patterns are mixed, The present invention can be applied.

BRIEF DESCRIPTION OF THE DRAWINGS It is an external view of Example 1 which applied this invention to the room lamp. 2 is a partially exploded perspective view of Example 1. FIG. It is the sectional view on the AA line of FIG. It is the BB sectional view taken on the line of FIG. It is a schematic block diagram of a light source and a light guide part. It is a figure which shows the light quantity distribution in the top view and side view explaining the effect | action of a light source and a light guide part, and a 1st light guide.

Explanation of symbols

RL Room lamp RF Ceiling 1 Lamp base 2 Cover 3 Lens 4 Light source 5 First light guide (linear light guide)
5a One end surface 5b Other end surface 6 Second light guide (planar light guide)
6a End face 11 Rear end part 12 Intermediate part 13 Both side parts 41 LED
51 Core 52 Light diffusing tube 61 Incident part 62 Small concave part (dot)

Claims (5)

  A first light guide having a linear shape from which light source light is incident from one end surface, and a second light guide having a planar shape from which light emitted from the other end surface of the first light guide is incident The first and second light guides are illumination devices configured to guide incident light by internally reflecting incident light and to emit part of the light from the surface as illumination light. In addition, at least two first light guides are provided, and the second light guide transmits a part of light incident from one first light guide to the other first light guide. An illuminating device having a structure capable of emitting light toward the other end surface.   The second light guide is formed in an arc shape having two end faces or substantially U-shaped, and each of the two first light guides is formed on the two end faces of the second light guide. The lighting device according to claim 1, wherein the other end surfaces are arranged to face each other.   3. The illumination according to claim 2, wherein the second light guide includes an incident portion recessed in a cylindrical shape on an end surface on which the other end surface of the first light guide is opposed. apparatus.   The lighting device according to claim 3, wherein a surface of the incident portion is roughened. The first light guide has a light diffusing tube on the surface, and the second light guide has a light diffusing step on the surface. The lighting device described in 1.

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