JP6101537B2 - Surface illumination device and vehicle emblem using the same - Google Patents

Description

  The present invention relates to a surface illumination device that guides and emits light from a plurality of light sources with a light guide, and a vehicle emblem using the same.

  2. Description of the Related Art Conventionally, there has been known a technology of a light emitting display device that uses a surface lighting device that guides and emits light from a light source with a light guide, and emits a vehicle emblem in a lateral direction along its outer shape and outline. (For example, Patent Document 1). In this vehicle emblem, when light is emitted from one light guide not only in the lateral direction of the emblem having a certain thickness but also in the front direction, light from the light source is incident on the thickness direction of the emblem and this direction It is necessary to guide light in a substantially vertical direction and emit the light in both directions of the emblem.

  As an example of this, a light source is disposed opposite to the incident surface of the light guide, and light from the light source incident from the incident surface is substantially perpendicular to the incident direction by a curved reflecting surface that rises obliquely from the incident surface. There is known a surface illumination device that guides light in any direction, reflects the light from the bottom surface of the light guide, and emits the light in the side and front directions (for example, Patent Document 2). The reflection surface of the light guide has a curved surface shape so that a large amount of incident light is totally reflected so that the amount of light that passes outward is reduced.

JP 2005-215596 A JP 2009-016087 A

  However, the vehicle emblem is provided with a restriction on the overall thickness (height space) defined by laws and regulations. In this state where the height is restricted, the reflection of the light guide as in Patent Document 2 is performed. It has not always been easy to form the surface into a curved shape so as to totally reflect as much light from the light source as possible according to the positions of the plurality of light sources. In addition, when the light guide is a curved reflecting surface, the large reflecting surface in the radial direction occupies the narrow space, which may hinder thinning.

  Further, as shown in FIG. 8, when a plurality of light sources are arranged side by side with respect to the curved reflecting surface 50, the reflecting surfaces 50 are assumed to be light sources A, B, and C in the order in which they are arranged from the side closer to the reflecting surface 50. In the light source A close to the light source, high light guide efficiency is obtained, but in the light source C far from the reflection surface, the light that passes outward from the flat portion 51 that is out of the curved reflection surface 50 increases, and the light guide efficiency decreases. To do. In this case, if the distance from the incident surface 52 to the reflecting surface 50 is increased, the curved reflecting surface 50 can achieve a certain degree of light guiding efficiency. However, there is a height limitation in the above-described vehicle emblem, and the curved surface It is difficult to improve the light guide efficiency with the shaped reflecting surface.

  The present invention solves the above-described problems, and has a simple structure and is thin, and can efficiently guide light from a plurality of light sources in a direction substantially perpendicular to the incident direction by a light guide. An object of the present invention is to provide an illumination device and a vehicle emblem using the surface illumination device.

  In order to achieve the above-described object, the present invention provides a criticality of the reflecting surface with respect to the incident surface when the reflecting surface extending obliquely from the incident surface of the light guide in which a plurality of light sources are arranged to face each other is linear. The present invention has been completed by paying attention to an inclination angle exceeding an angle and an arrangement relationship between the reflecting surface and the plurality of light sources.

  A surface illumination device according to one configuration of the present invention is formed by projecting a plurality of light sources and a light guide unit and one end of the light guide unit in a light guide reverse direction opposite to the light guide direction. A light guide having a light introduction portion for introducing light from a thickness direction orthogonal to the light guide reverse direction, and the light sources are arranged along the light guide reverse direction, and the light introduction portion Opposite to. The light introducing portion extends in the reverse direction of the light guide and faces the plurality of light sources, and extends obliquely and linearly from the outer edge of the incident surface, and the material of the light guide with respect to the incident surface. A reflective surface that is inclined at an acute angle with an angle greater than the critical angle of the light, reflects light incident in the thickness direction from the incident surface, and introduces the light into the light guide portion in the light guide direction. The light source is arranged so as to be deviated in the light guide reverse direction from the boundary between the obliquely reflecting surface and the light guide unit.

  According to this configuration, the reflection surface of the light introducing portion of the light guide is inclined at an acute angle with respect to the incident surface at an angle larger than the critical angle of the material of the light guide, and is incident on the incident surface in the thickness direction. The light source is introduced into the light guide unit in the light guide direction, and a plurality of light sources are arranged in the light guide reverse direction with respect to the boundary between the reflective surface extending obliquely and linearly and the light guide unit. Has been. Therefore, the multiple light sources are all arranged opposite to the reflecting surface in the thickness direction, and the reflecting surface totally reflects the incident light, so that the incident light is separated from the reflecting surface regardless of the position of the light source. The amount of incident light can be reduced, and the incident light can be totally reflected from the reflecting surface as much as possible. This makes it possible to guide light from a plurality of light sources with high light guide efficiency in a direction substantially perpendicular to the thickness direction (incident direction) (light guide direction) with a simple structure, Since the reflecting surface of the light introducing portion is linear, it is possible to reduce the thickness of the surface illumination device unlike the conventional curved shape.

  In the present invention, it is preferable that the plurality of light sources are arranged so that the luminance sequentially increases as the distance from the reflecting surface increases. In this case, in consideration of the fact that the light source far from the reflecting surface has a relatively lower light guide efficiency than the near light source, the entire light emission can be made uniform by increasing the brightness of the far light source. .

  Preferably, the light guide portion is provided with a gradually changing portion having a convex curved surface shape in the thickness direction adjacent to the incident surface of the light introducing portion. In this case, the guided light is less likely to escape outward as compared to the linear shape.

  Preferably, the incident surface of the light introducing portion is provided with a bent portion that is extended by inclining the incident surface far from the reflecting surface toward the light source. In this case, the light guide efficiency can be further improved.

  An emblem for a vehicle according to another configuration of the present invention is a emblem for a vehicle that is attached to a vehicle, and includes a case that is provided with a recess and does not have translucency, and that is provided on the upper portion of the case and has translucency. An outer lens, and the surface illumination device disposed between the outer lens and the case, the plurality of light sources of the surface illumination device having a thickness of the case. The light from the plurality of light sources is guided by the light guide and emitted in the front and side directions of the emblem so as to irradiate light in the direction. The

  According to this configuration, the surface illumination device provided in the vehicle emblem guides light from a plurality of light sources to the thickness direction (incident direction) and a direction (light guide direction) substantially perpendicular to the thickness direction (incident direction). Since the light can be guided well and the reflecting surface of the light introduction part is linear, the surface illumination device can be made thinner, unlike the conventional curved shape, so the light from multiple light sources is simple and thin. Can be emitted in the front and side directions of the emblem.

  The surface illumination device of the present invention has a simple configuration and is thin, and can efficiently guide light from a plurality of light sources in a direction substantially perpendicular to the incident direction by a light guide. Moreover, the vehicle emblem using this surface illumination device has a simple configuration and is thin, and can emit light from a plurality of light sources in the front and side directions of the emblem.

(A) is a perspective view which shows the principal part of the emblem for vehicles provided with the surface illumination apparatus concerning one Embodiment of this invention, (B) is a disassembled perspective view of the emblem for vehicles. It is a perspective view which expands and shows the light guide of a surface illumination apparatus. It is a perspective view which shows the surface illumination apparatus at the time of vehicle mounting. It is sectional drawing which shows the structure of a surface illumination apparatus. It is explanatory drawing which shows the simulation result of the optical path at the time of changing the inclination-angle of a reflective surface. It is sectional drawing in the AA of FIG. (A), (B) is sectional drawing which shows the light guide of a surface illumination apparatus. It is explanatory drawing which shows the simulation result of the optical path in a prior art.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. FIG. 1A is a perspective view showing a main part of a vehicle emblem provided with a surface illumination device according to an embodiment of the present invention, and FIG. 1B is an exploded perspective view of the vehicle emblem. 2 is an enlarged perspective view showing a light guide of the surface illumination device of FIG. FIG. 3 is a perspective view showing the surface illumination device when mounted on a vehicle. FIG. 4 is a cross-sectional view showing the configuration of the surface illumination device.

  As shown in FIG. 1B, a vehicle emblem 1 (hereinafter also simply referred to as an emblem) in which a case 7 is mounted on a vehicle (not shown) is a substantially plate-shaped member having a predetermined thickness. A surface illumination device AI including an outer lens 4 made of a light-transmitting material provided on the top, a plurality of light sources 6 and a light guide 5 that guides light from the plurality of light sources 6, and a plurality of light sources The board | substrate 17 which mounts 6 is provided in the recessed part 7a, and is provided with the case 7 which does not have translucency. The light guide 5 of the surface illumination device AI is bent into a shape that substantially matches the outer shape of the outer lens 4, and is disposed between the outer lens 4 and the case 7.

  The outer lens 4 is made of a light-transmitting material such as polycarbonate or acrylic resin. The case 7 is made of a synthetic resin such as an ABS resin. For example, a material in which fine particles having light scattering properties are dispersed for uniform light emission of the outer lens 4 may be used. Although not shown in the drawings, when the vehicle is mounted, a design body in which the surface of a molded body of a thermoplastic resin such as ABS resin is coated in a metallic manner by painting, plating or the like is installed on the outermost surface of the emblem 1.

  As shown in FIGS. 1 (A) and 1 (B), the outer lens 4 has a substantially elliptical outer shape, and is provided with a bridge portion 8 and a hollow portion 9 that is one step lower than the center portion. When viewed from the direction, only the edge 10 of the outline becomes the light emitting surface 3, and the light shielding surface 2 that is colored other than the edge 10 is covered. Further, the side portion 11 of the outer lens 4 does not have the light shielding surface 2, and as a result, the emblem 1 as a whole has a configuration in which the light emitting surface 3 exists in a part in the front direction and in the side surface direction. The outer shape and outline of the emblem 1 and the arrangement of the light shielding surface 2 and the light emitting surface 3 are not limited to this.

  In this way, the configuration of the emblem 1 and the edge 10 of the side portion 11 of the outer lens 4 are the light emitting surface 3 and the rest is the light shielding surface 2, so that the emblem 1 has a contour as shown in FIG. Light Lf in the front direction is emitted from the portion along the side, and light Ls in the side direction is emitted from the portion along the side portion 11 of the outer lens 4.

  Further, as shown in FIG. 1B, in this embodiment, another light source 36 is provided near the top of the bridge portion 8. This is for improving the design by balancing the whole by emitting light with the highest brightness from the center of the emblem 1 toward the front direction. The light emission direction of the separate light source 36 is defined as the front direction. Thus, a configuration is adopted in which light is incident in the arrangement of the substrate 17, and hence the arrangement of the light source 6 and the thickness direction d of the emblem 1. In addition, apart from the substrate 17 set to a surface substantially perpendicular to the front direction, a substrate is added to a surface substantially parallel to mount the light source 6, and light is emitted from the same direction as the light guide direction X0 of the light guide 5. Incidence is also possible, but there are problems such as an increase in cost, a limitation on the height space of the emblem 1, and a shadow of the substrate reflected on the light emitting surface. The present method is preferred.

  The surface illumination device AI includes a plurality of light sources 6 and a light guide 5 that guides light from the plurality of light sources 6, and the light guide 5 includes a light guide 5A and a light guide as shown in FIG. A light introducing portion that is formed so as to protrude from one end of the portion 5A in the light guide reverse direction X opposite to the light guide direction X0 and introduces light from the plurality of light sources 6 from the thickness direction d orthogonal to the light guide reverse direction X. 5B. For example, LEDs are used for the plurality of light sources 6, and acrylic resin, polycarbonate, or the like is used for the light guide 5.

  As shown in FIG. 2, the light guide 5 is formed in a substantially elliptical rod shape so as to substantially match the outer shape of the outer lens 4 in FIG. 1B, and along the contour of the outer lens 4, The outer lens 4 extends from the left and right sides of the bridge portion 8 according to the shape of the side portion 11, and is attached and fixed to the case 7 by the attachment portion 12. The left and right ends of the light guide 5 are formed with the incident surface 13 and a linear reflecting surface 15 inclined from the tip 14 (outer edge) of the incident surface 13.

  Further, as shown in FIG. 3, the plurality of light sources 6 emit a plurality of different colors, and a plurality of LEDs are mounted on a substrate 17 made of glass epoxy resin or the like. The plurality of light sources 6 arranged side by side on the same plane are configured to emit light in the thickness direction d of the case 7. In the present embodiment, four of the six LEDs are configured by an LED light source 6b that emits a low-luminance color, and two of them are configured by an LED light source 6a that emits a high-luminance color. The light source 6b is disposed on the side close to the reflecting surface 15, and the high-intensity light source 6a is disposed on the side far from the reflecting surface 15. The low-brightness and high-brightness colors mentioned here mean relative heights when compared with each other. For example, the low-brightness light source 6a can be blue and the high-brightness light source 6b can be white. In addition, the luminescent color, number, etc. of LED are not limited to this.

  Hereinafter, the configuration of the surface illumination device AI will be described in detail with reference to FIG. The plurality of light sources 6 are arranged to face each other along the light guide reverse direction X, and face the light introducing portion 5 </ b> A of the light guide 5. The light introducing portion 5A extends in the light guide reverse direction X and faces the plurality of light sources 6, and extends obliquely linearly from the outer edge of the incident surface 13 and tilts at an acute angle with respect to the incident surface 13. And a reflecting surface 15. The reflection surface 15 has an angle (inclination angle) θ that is inclined at an acute angle from the tip 14 larger than the critical angle of the material of the light guide 5. For example, when an acrylic resin is used as the material of the light guide 5, the inclination angle θ is set larger than the critical angle 42 °.

  At this time, the reflecting surface 15 reflects light incident in the thickness direction d from the incident surface 13 substantially vertically on the inner surface thereof, and introduces the light into the light guide unit 5B in the light guide direction X0. On the other hand, the plurality of light sources 6 are displaced in the light guide reverse direction X with respect to the boundary P between the reflection surface 15 and the light guide portion 5 extending obliquely, that is, arranged outside the light guide reverse direction X. Accordingly, all of the plurality of light sources 6 are arranged opposite to the reflecting surface 15 and the reflecting surface 15 totally reflects the incident light, so that the incident light is reflected on the reflecting surface 15 regardless of the arrangement of the plurality of light sources 6. Thus, it is possible to reduce the number of incident light beams from the reflecting surface 15 as much as possible.

  Accordingly, in the conventional curved reflection surface, the light guide efficiency of the light source arranged at a position far from the reflection surface among the plurality of light sources is remarkably lowered. In the present invention, the reflection surface 15 is far from the reflection surface 15. The light source 6a arranged at a position can also be totally reflected on the reflecting surface 15 to improve the light guide efficiency. Moreover, since the reflecting surface 15 of the light guide 5 is linear, the reflecting surface does not increase in the radial direction as in the case of a conventional curved reflecting surface. Even if a light source is arranged, the dimension in the thickness direction (matching the radial direction of the reflecting surface) of this portion is reduced, and a reduction in thickness can be realized.

  The plurality of light sources 6 are arranged side by side in the light guide reverse direction X in the same plane substantially parallel to the incident surface 13, and the low-intensity light source 6 b is positioned closer to the reflection surface 15 and the high-intensity light source 6 a. Is arranged on the side far from the reflecting surface 15. In consideration of the fact that the light source 6a farther than the light source 6b closer to the reflecting surface 15 has a relatively lower light guiding efficiency, the high-intensity light source 6a is placed closer to the side farther from the reflecting surface 15. By disposing the low-intensity light source 6b, the entire light emission of the plurality of light sources 6 can be made uniform.

  Further, the light guide 5 is formed with a convex curve-shaped gradual change portion 18 protruding in the incident direction (thickness direction d) adjacent to the incident surface 13 of the light introducing portion 5A. The lower light guide surface 19b is connected. Thereby, compared to the configuration in which the incident surface 13 and the lower light guide surface 19b are linearly connected, the light reflected by the reflecting surface 15 of the light introducing portion 5A is reflected further by the gradual change portion 18, It is possible to guide light more efficiently.

  4, the distance (height) between the upper light guide surface 19a and the lower light guide surface 19b in the incident direction (thickness direction d) in the light guide 5 is H1, and the upper light guide surface 19a and the incident surface 13 are The distance (height) is H2, the distance (width) of the reflecting surface 15 in the light guide reverse direction X is L1, the distance (width) of the incident surface 13 is L2, and the angle (tilt angle) of the tip 14 is θ. The total distance (width) in the light guide direction of the light source 6 is L0. In this case, since the light guide efficiency of the plurality of light sources 6 becomes closer to the reflecting surface 15, L0 is configured to be kept to a minimum, but there is a limit depending on the number and specifications of the LEDs, and this embodiment When arranged in three columns, L0 = 10 mm is constrained as a minimum value. As the values of H1 and H2 are larger, the light guide efficiency can be improved. However, there is a limitation due to commercial properties and regulations as a vehicle emblem, and in this embodiment, H1 = 8 mm and H2 = 10 mm. Therefore, in order to guide the light from the plurality of light sources 6 in a direction substantially perpendicular to the incident direction with high light guide efficiency under the various restrictions as described above, the shape of the reflective surface 15, L1 It is necessary to devise the configuration of the distance and the inclination angle θ.

  FIG. 5 is an explanatory diagram showing a simulation result of the optical path when the inclination angle θ of the reflecting surface is changed. (A) is when θ = 35 °, (B) is when θ = 55 °, and is outside the scope of the present invention, and (C) is within the scope of the present invention when θ = 45 °. First, when θ = 35 ° as shown in (A), most of the light sources A, B, and C arranged in the order closer to the reflecting surface pass out of the light guide from the reflecting surface. You can see that it is closed. This is because most of the light incident on the light guide 5 is transmitted when it strikes the reflecting surface 15 at an angle larger than the critical angle 42 ° of the acrylic resin.

  In addition, when θ = 55 ° as in (B), light is efficiently guided in the light sources A and B, but most light is guided in the light source C farthest from the reflecting surface. You can see that it has slipped out of. This is because there is a limit in the height direction of the light guide, and if the inclination angle θ is increased, the distance of the reflecting surface (L1 described above) decreases, and the light source C located farthest from the reflecting surface is located directly above the light source C. This is because there is no reflecting surface. As a result, the light directly above with the highest luminance is transmitted through the LED light source, so that the light guide efficiency is significantly reduced.

  And when (theta) = 45 degrees like (C), while the reflective surface 15 exceeds a critical angle, the reflective surface 15 exists just above the light source C furthest from the reflective surface 15, ie, several The light source 6 is disposed outside the light guide reverse direction X with respect to the boundary P between the reflective surface 15 extending obliquely and the light guide portion 5B. Therefore, it can be seen that the problems in the cases (A) and (B) described above have been solved, and that the light sources A, B, and C are all guided in a balanced manner. Since the critical angle of the acrylic resin used for the light guide 5 is 42 ° and the inclination angle θ of the reflecting surface 15 of the light introducing portion 5A is 45 ° exceeding this, the light introducing portion 5A has the incident surface 13. And the reflecting surface 15 have a substantially cross-sectional (right-angled) triangular shape, and the light guide 5 can be easily formed. Similarly, a polycarbonate resin having a critical angle of 39 ° can also be preferably used.

  Thus, in the present invention, the reflecting surface 15 of the light introducing portion 5A of the light guide 5 is inclined at an acute angle with respect to the incident surface 13 at an angle larger than the critical angle of the material of the light guide 5 (inclination angle). θ), the light incident from the thickness direction d is reflected in a substantially vertical direction and introduced into the light guide unit 5B, and the plurality of light sources 6 includes a reflection surface 15 and a light guide unit 5B obliquely extending linearly. And is deviated in the light guide reverse direction X from the boundary P. Accordingly, the plurality of light sources 6 are all arranged opposite to the reflecting surface 15 in the thickness direction d, and the reflecting surface 15 totally reflects the incident light, so that the incident light is reflected regardless of the position of the light source 6. Therefore, it is possible to reduce the number of incident light beams from the reflecting surface 15 as much as possible. Thus, the light from a plurality of light sources 6 can be guided with high light guide efficiency in the direction substantially perpendicular to the thickness direction d (incident direction) (light guide direction X0) by the light guide 5 with a simple configuration and a thin shape. Is possible.

  In the vehicle emblem 1 described above, a state in which the guided light is emitted from the light guide 5 of the surface illumination device AI and emitted to the outside of the emblem 1 will be described. FIG. 6 is a cross-sectional view taken along the line AA in FIG. 1, and an optical pattern 20 is formed on the bottom surface of the light guide 5 opposite to the emission surface 21 with fine concave and convex shapes and laser dots. Thereby, a part of the light incident from the plurality of light sources 6 and guided through the light guide 5 in the light guide direction X0 changes its direction and is emitted from the emission surface 21 to be the edge of the outer lens 4. 10 and the side part 11 and become the light emitting surface 3 and appear on the surface of the emblem. As shown by the broken line arrow in the figure, the light in the front direction from the part along the outline of the edge part 10 of the emblem 1 Lf emits light Ls in the side surface direction from the portion along the side portion 11 (FIG. 1A).

  As described above, in the present invention, the light from the plurality of light sources 6 is guided to the direction substantially perpendicular to the incident direction by the light guide 5 with a simple structure and thin by the surface illumination device provided in the vehicle emblem. It becomes possible to guide light efficiently. This makes it possible to emit multiple colors of light in the front and side directions of the emblem without increasing the overall thickness or adding extra light sources or light guides. A highly emblem for a vehicle can be obtained.

  Note that, as in the modification of the light guide 5 shown in FIG. 7B, the incident surface 13 of the light guide 5 is the light source 6 side (the diagonally lower left in the drawing) the incident surface far from the reflecting surface 15. It can be set as the shape in which the bending part 13a inclined and extended was provided. As a result of the optical path simulation, the modified example in FIG. 7B can reduce the light that escapes from the (upper) light guide surface 19a, compared with the embodiment in FIG. It can be improved by about 15%.

  In this embodiment, the light guide unit 5 is provided with the gradual change unit 18, but may be omitted as necessary.

1: emblem 2: light-shielding surface 3: light-emitting surface 4: outer lens 5: light guide 5A: light guide 5B: light guide 6: light source 7: case 13: incident surface 13a: bent portion 15: reflecting surface 18 : Gradual change part AI: Surface illumination device d: Thickness direction P: Intersection X0: Light guide direction
X: reverse direction of light guide θ: inclination angle

Claims (3)

A plurality of light sources and a light guide unit and one end of the light guide unit are formed so as to protrude in the light guide reverse direction opposite to the light guide direction, and the light of the plurality of light sources from the thickness direction orthogonal to the light guide reverse direction A light guide having a light introduction part to be introduced , and reducing light emission to the outside of the light guide,
The plurality of light sources are arranged side by side along the reverse direction of the light guide and are opposed to the light introduction part, and are arranged so that the luminance sequentially increases as the distance from the reflection surface increases.
The light introducing portion extends in the reverse direction of the light guide and faces the plurality of light sources, and extends obliquely and linearly from the outer edge of the incident surface, and the material of the light guide with respect to the incident surface. A reflective surface that is inclined at an acute angle with an angle larger than the critical angle, and reflects light incident in the thickness direction from the incident surface and introduces the light into the light guide section in the light guide direction,
The plurality of light sources are arranged to be deviated in the light guide reverse direction from the boundary between the obliquely reflecting surface and the light guide part ,
The light guide unit is a surface illumination device in which a gradually changing portion having a convex curved surface shape is provided in a thickness direction adjacent to an incident surface of the light introducing unit . In claim 1,
The surface illumination device, wherein a bent portion is provided on the incident surface of the light introducing portion, wherein an incident surface far from the reflecting surface is inclined and extended toward the light source. An emblem for a vehicle to be mounted on a vehicle, which has a concave portion and is not translucent, a translucent outer lens that is provided at the top of the case, and a shape that substantially matches the outer shape of the outer lens The surface illumination device according to claim 1 or 2 , wherein the surface illumination device is disposed between the outer lens and the case.
The plurality of light sources of the surface illumination device are arranged on the same plane in the recess so as to emit light in the thickness direction of the case, and light from the plurality of light sources is guided by the light guide. A vehicle emblem that is illuminated and emitted in the front and side directions of the emblem.

Images