JP2013171658A - Light guide member and vehicular lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate shape design of a light guide member, without causing light-emitting unevenness, while using the light guide member having a curved part.SOLUTION: A light guide member 22 includes a light-guiding body part extended with a curved part 22c. A plurality of steps 23 are arranged along an extension direction of the body part. Light entering one end 22e of the body part from a light source and reflected by the steps 23 is emitted from a light-emitting part 22g. A plurality of uneven parts 24 are formed at least at a part corresponding to the curved part 22c out of the light-emitting part 22g.

Description

  The present invention relates to a light guide member that guides light emitted from a light source in a predetermined direction, and a vehicular lamp including the light guide member.

  A configuration in which a light source and a long light guide member are disposed in a lamp chamber of a vehicular lamp is known (see, for example, Patent Document 1). The light emitted from the light source is guided to the region where the reflection surface (step) is formed while totally reflecting the inside of the light guide member, and is reflected by the step to be emitted to the outside of the light guide member to be predetermined. Irradiate the area.

JP 2011-238582 A

  By forming a step over the entire back surface of the light guide member (surface facing the vehicle inner side) and providing a curved portion in the light guide member as described in Patent Document 1, the surface of the light guide member (surface facing the vehicle outer side) is formed. ) The entire surface can emit light to increase the light distribution angle (irradiation range) or provide a novel light emitting appearance.

  However, in the curved portion, unlike the portion where the light guide member extends in a straight line, the directivity of the emitted light is partially uneven, resulting in uneven light emission. In order to eliminate the uneven light emission, it is necessary to adjust the shape of each step, which is a burden in designing the shape of the light guide member.

  Therefore, an object of the present invention is to provide a technique capable of facilitating the shape design of the light guide member without causing uneven light emission while using the light guide member having a curved portion.

In order to achieve the above object, the first aspect of the present invention can be a light guide member,
A light-guiding body portion having at least one curved portion and extending;
A plurality of steps arranged along a direction in which the main body extends;
A light emitting part that emits light that is incident on one end of the main body from the light source and reflected by the step;
A plurality of concavo-convex portions are formed in at least a part of the light emitting portion corresponding to the curved portion.

In order to achieve the above object, the second aspect of the present invention is a vehicle lamp,
A housing that partitions the lamp chamber;
A light guide member disposed in the lamp chamber and extending with at least one curved portion;
A light source disposed in the lamp chamber,
The light guide member includes a plurality of steps arranged along the direction in which the light guide member extends, and a light emitting portion from which light incident on one end of the main body from the light source and reflected by the step is emitted. And are formed,
A plurality of concavo-convex portions are formed in at least a part of the light emitting portion corresponding to the curved portion.

  According to the above configuration, the light emitted through the concavo-convex portion among the light reflected by the step is diffused, so that the curved portion is visually recognized as emitting light uniformly. Therefore, it is not necessary to strictly adjust the step shape in order to eliminate unevenness in light emission. Moreover, since it is sufficient to form an uneven | corrugated | grooved part as what has a light-diffusion function, the burden on the shape design of a light guide member can be reduced.

  The curved portion includes a first portion that is curved with a first curvature and a second portion that is curved with a second curvature larger than the first curvature, and the uneven portion is formed in the second portion. It is good also as the structure currently made. By forming the concavo-convex portion only in a portion with a high curvature that is more likely to cause uneven light emission, the occurrence of uneven light emission can be effectively prevented while suppressing processing costs.

  The concavo-convex portions may be a plurality of ridges arranged in a direction in which the main body portion extends and each extending in a direction intersecting with the direction in which the main body portion extends. In this case, since the emitted light can be actively diffused in the direction in which the main body extends, a large viewing angle can be ensured.

  In the case where the plurality of protrusions have curved surfaces, the aesthetic appearance can be enhanced even when the light guide member is not emitting light.

It is a front view showing typically composition of a vehicular lamp concerning one embodiment of the present invention. FIG. 2 is a partial cross-sectional view taken along line II-II in FIG. 1 and shows a structure for attaching a light guide member to a vehicle lamp. It is a figure which shows the external appearance of the light guide member in FIG. 1, (a) is a left view, (b) is a top view, (c) is a rear view. FIG. 4 is a partial cross-sectional view taken along line IV-IV in FIG. 1, schematically showing a relationship between a reflection step and an emission step in the light guide member in FIG. 3.

  The present invention will be described in detail below with reference to the accompanying drawings. In each drawing used in the following description, the scale is appropriately changed to make each member a recognizable size.

  FIG. 1 is a front view schematically showing a configuration of a vehicular lamp 1 according to an embodiment of the present invention. A vehicular lamp 1 is installed at a left front end of a vehicle, and a headlamp unit 10 and a width lamp unit 20 are housed in a lamp chamber 3 defined by a lamp housing 2 as a casing of the present invention. Yes. Since the headlamp unit 10 has a well-known configuration, a detailed description is omitted.

  FIG. 2 is a partial cross-sectional view taken along line II-II in FIG. 1 and shows a structure for attaching the vehicle width lamp unit 20 to the vehicle lamp 1. The lamp chamber 3 is defined by the above-described lamp housing 2 and a light-transmitting cover 4 attached to the front end thereof. Reference numeral 5 denotes an extension that shields the inside of the lamp chamber 3 from the outside.

  The vehicle width lamp unit 20 includes a light source unit 21 and a light guide member 22, and is disposed at the front end of the lamp chamber 3 so that the light guide member 22 extends along the inner surface of the translucent cover 4. The light source unit 21 is configured such that a light emitting element 21a as a light source of the present invention is supported by a substrate 21b. In the present embodiment, the light emitting element 21a is a white light emitting diode.

  FIG. 3 shows an appearance of the light guide member 22 according to an embodiment of the present invention. (A) is a left side view, (b) is a plan view, and (c) is a rear view. The light guide member 22 has a prismatic transparent main body made of a resin such as polymethyl methacrylate or polycarbonate. The main body has a front end 22a, a first bending portion 22b, a second bending portion 22c, a third bending portion 22d, and a rear end 22e.

  In a state where the light guide member 22 is stored in the vehicle lamp 1, the front end portion 22 a is disposed near the vehicle center at the front end portion of the lamp chamber 3. The first curved portion 22b is a portion that extends in a straight line from the front end portion 22a to the diagonally upper part of the vehicle while gently curving diagonally left rearward of the vehicle (see FIG. 1).

  The second bending portion 22c is a portion that is continuous with the rear end of the first bending portion 22b and curves backward and obliquely upward with a larger curvature than the first bending portion 22b.

  The third curved portion 22d is a portion that is continuous with the rear end of the second curved portion 22c, and that extends in a straight line to the rear of the vehicle while gently bending obliquely upward of the vehicle. The rear end portion 22e is continuous with the rear end of the third curved portion 22d and is disposed closer to the vehicle outer side at the rear end portion of the lamp chamber 3.

  A recess 22f is formed on the rear end surface of the rear end 22e. As shown in FIG. 2, in a state where the light guide member 22 is disposed in the lamp chamber 3, the light emitting element 21a supported by the substrate 21b is accommodated in the recess 22f.

  The main body of the light guide member 22 has a front side 22g and a back side 22h. When the light guide member 22 is disposed in the lamp chamber 3, the front side surface 22g is a surface substantially facing the outside of the vehicle, and the back side surface 22h is a surface substantially facing the inside of the vehicle. The light guide member 22 is twisted at the second curved portion 22c, and the front side surface 22g faces upward of the vehicle and the back side surface 22h faces downward of the vehicle at the third curved portion 22d and the rear end portion 22e.

  As shown in FIG. 3 (c), a plurality of reflection steps 23 are arranged along the extending direction of the main body part over substantially the entire back side surface 22h. The reflection step 23 as a step of the present invention is formed as a ridge extending in a direction intersecting with the extending direction of the main body, and forms alternately a trough line 23a and a ridge line 23b as shown in FIG. It has an inclined surface 23c.

  The light emitted from the light emitting element 21a of the light source unit 21 enters the rear end portion 22e as one end of the main body portion. Incident light travels along the extending direction of the main body while being totally reflected by the inner surface 22 i of the light guide member 22, and a part of the incident light is reflected by the internal reflection surface 23 d formed by the inclined surface 23 c of the reflection step 23. The

  A part of the light reflected by the internal reflection surface 23d is emitted from a part of the front side surface 22g of the light guide member 22 without being totally reflected by the inner surface 22i of the light guide member 22, and is visually recognized as illumination light. In the following description, a portion from which the light reflected by the reflection step 23 is emitted is referred to as a light emitting portion.

  As shown to (a) and (b) of FIG. 3, the several emission step 24 is arranged along the direction where a main-body part is extended in the part corresponding to the 2nd curved part 22c of 22 g of front side surfaces. Each of the emission steps 24 as the concavo-convex portion of the present invention is formed as a ridge extending in a direction intersecting with the extending direction of the main body, and has a curved surface 24a as shown in a cross section in FIG. .

  As shown in FIG. 4, among the light reflected by the internal reflection surface 23d, the light emitted from the light emitting portion 25 where the emission step 24 is not formed has a relatively coincident directivity. On the other hand, the light emitted through the emission step 24 is diffused by the curved surface 24a.

  The light emission unevenness that tends to occur in the curved portion of the light guide member is caused by the unevenness of the directivity of the emitted light due to the curvature of the light emitting portion. In the present embodiment, the occurrence of uneven light emission is prevented by positively losing the coincidence of directivity of emitted light by the diffusion effect of the curved surface 24a. As a result, the second curved portion 22c on the front side surface 22g is visually recognized as emitting light uniformly.

  Therefore, it is not necessary to strictly adjust the shape of the reflection step 23 in order to eliminate unevenness in light emission. Furthermore, since it is sufficient that the emission step 24 is formed as a concavo-convex portion having a light diffusing function, a burden in designing the shape of the light guide member 22 can be reduced.

  The emission step 24 is formed only on the second bending portion 22c having a curvature (second curvature) larger than the curvature (first curvature) of the first bending portion 22b and the third bending portion 22d. By forming the emission step 24 only in a portion with a high curvature that is more likely to cause uneven light emission, the occurrence of uneven light emission is effectively prevented while suppressing processing costs.

  Further, since each of the emission steps 24 is formed as a protrusion extending in a direction intersecting with the direction in which the light guide member 22 extends, the emitted light can be actively diffused in the direction in which the light guide member 22 extends. Since the light emission step 24 formed in the second bending portion 22c shown in FIG. 3B can also distribute light to the first bending portion 22b and the third bending portion 22d, the viewing angle can be increased. .

  Furthermore, since the surface of the emission step 24 that is directly visually recognized through the translucent cover 4 when the light emitting element 21a is turned off has a curved shape, it is possible to enhance the aesthetic appearance.

  The above embodiment is for facilitating understanding of the present invention, and does not limit the present invention. The present invention can be modified and improved without departing from the spirit of the present invention, and it is obvious that the present invention includes equivalents thereof.

  The light guide member 22 does not need to include a plurality of curved portions as in the above-described embodiment, and may have a configuration having at least one curved portion depending on the application. Further, the emission step 24 does not need to be formed on the entire curved portion, and may be formed on at least a part thereof. For example, when one curved portion has a portion with a small curvature (first portion) and a portion with a large curvature (second portion), the emission step 24 is formed only on the second portion where light emission unevenness is more likely to occur. Thus, it is possible to effectively prevent the occurrence of uneven light emission while suppressing the processing cost.

  The shape of the emission step 24 does not need to be a protrusion having a curved surface 24a as in the above embodiment. As long as the light reflected by the reflection step 23 can be diffused, it can have any irregular shape.

  The light emitted from the light emitting element 21 a may be configured to enter from the front end portion 22 a of the light guide member 22. The light emitting element 21a is not limited to a white light emitting diode, and a laser diode or the like may be used. A lamp light source may be used instead of the light emitting element.

  DESCRIPTION OF SYMBOLS 1: Vehicle lamp, 2: Lamp housing, 3: Lamp chamber, 21a: Light emitting element, 22: Light guide member, 22a: Front end part, 22b: 1st bending part, 22c: 2nd bending part, 22d: 3rd Curved portion, 22e: rear end portion, 22g: front side surface, 22h: back side surface, 23: reflection step, 24: emission step, 24a: curved surface

Claims (5)

A light-guiding body portion having at least one curved portion and extending;
A plurality of steps arranged along a direction in which the main body extends;
A light emitting part that emits light that is incident on one end of the main body from the light source and reflected by the step;
A light guide member in which a plurality of concave and convex portions are formed in at least a part of the light emitting portion corresponding to the curved portion. The bending portion includes a first portion that bends with a first curvature and a second portion that bends with a second curvature that is greater than the first curvature,
The light guide member according to claim 1, wherein the uneven portion is formed in the second portion.   The light guide member according to claim 1, wherein the concavo-convex portions are a plurality of protrusions arranged in a direction in which the main body portion extends, each extending in a direction intersecting with the direction in which the main body portion extends.   The light guide member according to claim 3, wherein each of the plurality of protrusions has a curved surface. A housing that partitions the lamp chamber;
A light guide member disposed in the lamp chamber and extending with at least one curved portion;
A light source disposed in the lamp chamber,
In the light guide member,
A plurality of steps arranged along the extending direction of the light guide member;
A light emitting part is formed from which the light that is incident on one end of the main body from the light source and reflected by the step is emitted;
A vehicle lamp, wherein a plurality of concave and convex portions are formed in at least a part of the light emitting portion corresponding to the curved portion.

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