JP5745335B2 - Light guide lens and vehicle lamp - Google Patents

Description

  The present invention relates to a light guide lens and a vehicular lamp including the same.

  2. Description of the Related Art Conventionally, as a vehicular lamp such as an automobile headlamp, a vehicular lamp that emits a long light guide lens to mainly form a sub-light distribution for decoration is known (for example, see Patent Document 1).

  In this type of vehicle lamp, as shown in FIG. 6, the long light guide lens 80 is in a state of being bent by the two bending portions 80a and 80a so as to form a U-shape that opens to the side, It is arranged along the opening periphery of the housing 70 whose front surface is open. The light guide lens 80 is formed in a substantially rectangular shape in cross section perpendicular to the longitudinal direction, and has a prism cut (not shown) formed on the rear surface over the entire length. In addition, light sources 90 and 90 that emit light from the light guide lens 80 are disposed at positions facing both end faces 80 b and 80 b in the longitudinal direction of the light guide lens 80.

  With such a configuration, in the above vehicle lamp, when the light sources 90 and 90 emit light, the light enters the light guide lens 80 from both end faces 80b and 80b, and is internally guided repeatedly in the longitudinal direction. However, as a result of being reflected from the prism cut on the rear surface and emitted from the front surface, the front surface of the light guide lens 80 emits light over the entire length.

US Pat. No. 5,984,497

  By the way, recent vehicle lamps may be formed in a shape in which the front surface is inclined rearward from the vehicle center side toward the vehicle side side due to requirements in vehicle body design. In such a vehicular lamp, the light guide lens 80 is similarly inclined, so that the front surface (light exit surface) of the light guide lens 80 is inclined obliquely with respect to the vehicle front-rear direction. It will turn.

  Therefore, in the extending portion 80c of the light guide lens 80 extending in the vertical direction, the light reflected by the rear prism cut is oblique to the lamp side (vehicle side) as shown in FIG. In addition, a part of the rear surface, which is a reflection surface, is shielded by the side surface 80d on the front side of the lamp (the front side of the vehicle) and cannot be viewed from the front of the lamp. Therefore, the extended portion 80c cannot be brightly illuminated with respect to the front of the lamp.

  The present invention has been made in view of the above circumstances, and even when arranged obliquely in the left-right direction, the extending portion extending in the up-down direction can emit light brightly with respect to the front. An object of the present invention is to provide a light guide lens that can be used and a vehicle lamp including the same.

In order to solve the above-mentioned problem, the invention described in claim 1
A plurality of prisms provided in a lamp chamber of a vehicular lamp and having a plurality of prism cuts on substantially the entire length on the rear surface while guiding light incident from both end surfaces in the longitudinal direction. In the light guide lens that is reflected by the cut and emitted from the front,
A straight portion extending substantially along the left-right direction;
Extending substantially along the vertical direction and having an extending portion connected to the linear portion and the end portion ;
The extending portion has the front surface, the rear surface, one side surface, and the other side surface, and a cross section perpendicular to the extending direction is formed in a substantially rectangular shape,
The front surface is a surface inclined from the one side surface toward the other side surface toward the rear of the vehicular lamp, and the reference surface is expanded forward so as to diffuse the emitted light in the left-right direction. It is formed in a raised convex shape,
It said rear surface, a base surface on which the plurality of prisms cut is formed is formed substantially parallel to the said reference plane Rutotomoni, narrowly formed than the width of the width of the reference plane,
The one side surface intersects the front surface so that an internal angle formed with the reference surface is an acute angle in a cross section orthogonal to the extending direction, and extends along the front-rear direction of the vehicular lamp and It is formed on the center side of our vehicle,
The other side surface is a cross section orthogonal to the extending direction so that a part of the light internally reflected by the rear surface is internally reflected forward and the other part of the light is transmitted. in, an interior angle formed between the reference plane Ri Majiwa and the front so that the obtuse angle, and characterized in that it is formed on the side of the vehicle side of the extending portion.

The invention according to claim 2 is the light guide lens according to claim 1 ,
Two straight portions extending in a direction substantially orthogonal to the vertical direction are connected to the upper and lower ends of the extended portion,
The front end surfaces of the two straight portions are the both end surfaces that allow light to enter the light guide lens.

The invention according to claim 3 is the light guide lens according to claim 1 or 2 ,
The plurality of prism cuts are:
Each prism cut formed in a shape constricted backward toward the longitudinal direction is arranged along the longitudinal direction,
The cut pitch between adjacent prism cuts is 0.3 mm or less.

The invention according to claim 4 is a vehicle lamp,
The light guide lens according to any one of claims 1 to 3 ,
Two light sources individually opposed to the both end faces of the light guide lens;
A housing that holds the light guide lens and the two light sources so that the light guide lens is disposed along the periphery of the opening, and the front surface is formed in an open shape.
It is characterized by providing.
The invention according to claim 5 is the vehicle lamp according to claim 4,
The light guide lens includes a reflecting member that is disposed to face the other side surface and reflects the light that has been internally reflected on the rear surface and transmitted through the other side surface to the front side.

According to the present invention, of the light guide lens provided in the lamp chamber of the vehicular lamp, the extending portion extending substantially along the vertical direction is for the vehicle from one side surface side to the other side surface side. A front surface having a reference surface that is inclined rearward of the lamp has a base surface on which a plurality of prism cuts are formed, and a rear surface that is formed substantially parallel to the reference surface. In the cross-section perpendicular to the extending direction of the existing part, it intersects with the front surface so that the internal angle formed with the reference surface becomes an acute angle, so unlike the conventional case where the extending part is formed in a simple cross-sectional rectangular shape, On the other hand, the one side surface located on the front side of the lamp is inclined so as to open to the front side of the lamp. Therefore, the rear surface, which is the reflection surface, can be seen more widely when viewed from the front of the lamp, compared to the conventional case where a part of the rear surface, which is the reflection surface, is shielded by the side surface on the front side of the lamp.
Further, the other side surface of the extending portion intersects the front surface so that the internal angle with the reference surface becomes an obtuse angle in a cross section orthogonal to the extending direction of the extending portion, that is, the other side surface and the rear surface ( Since the inner angle with the base surface is an acute angle, a part of the light reflected by the prism cut on the rear surface is reflected to the front side of the lamp by the other side surface. Therefore, the amount of light emitted to the front side of the lamp can be increased as compared with the conventional case where all the light reflected on the rear surface is emitted obliquely to the side of the lamp.
In addition, the front surface of the extension is formed in a convex shape with the reference surface bulging forward so as to diffuse the emitted light in the left-right direction, so that it is reflected obliquely to the lamp side by the prism cut on the rear surface. The diffused light can be diffused widely to the front side of the lamp by the front surface.
As described above, even when it is disposed obliquely in the left-right direction, the extending part extending in the up-down direction can be brightly emitted with respect to the front of the lamp as compared with the conventional case.

It is a perspective view of the vehicular lamp in an embodiment. It is a perspective view of the light guide lens in an embodiment. It is a fragmentary sectional view along the longitudinal direction of the light guide lens in an embodiment. It is sectional drawing in the II-II line | wire of FIG. It is sectional drawing which shows the example of a shape of the extension part in embodiment. It is a front view of the conventional light guide lens and its light source. It is a figure which shows the light ray locus | trajectory in the extension part of the conventional light guide lens.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of a vehicular lamp 1 according to the present embodiment, FIG. 2 is a perspective view of a light guide lens 5 provided in the vehicular lamp 1, and FIG. FIG. 4 is a cross-sectional view taken along line II-II in FIG. 2.
In the following description, unless otherwise specified, “front”, “rear”, “left”, “right”, “upper”, and “lower” are described in the direction viewed from the vehicular lamp 1. It shall be used in correspondence with the description of the drawing as indicating the direction seen from the vehicle not shown.

  As shown in FIG. 1, a vehicular lamp 1 is a headlamp mounted on a front left side of a vehicle (not shown), and includes a housing 2 whose front surface is opened and an outer lens (not shown) that covers the front opening of the housing 2. I have. The opening surface of the housing 2 is inclined obliquely rearward from the right side (vehicle center side) to the left side (vehicle side side), and the front surface of the outer lens is similarly inclined. In the lamp chamber formed by the housing 2 and the outer lens, the main light distribution unit 4 that forms the main light distribution is disposed at substantially the center, and the long light guide lens 5 that forms the sub light distribution is the housing. It arrange | positions so that 2 opening periphery may be followed.

  As shown in FIG. 2, the light guide lens 5 is formed in a substantially U shape that opens rightward in a front view, and is held by the housing 2. Specifically, the light guide lens 5 includes an upper first linear portion 51 that extends substantially in the left-right direction in a front view, a lower second linear portion 52 that is substantially parallel to the first linear portion 51, and upper and lower And an extended portion 53 extending substantially along the direction, and both left ends of the first straight portion 51 and the second straight portion 52 are connected to the upper and lower ends of the extended portion 53 via a curved portion. Is formed. The first straight portion 51 extends from the end surface 51 a over a predetermined length, and the second straight portion 52 extends from the end surface 52 a over a shorter length than the first straight portion 51. Yes.

  Light sources 6 and 6 for causing the light guide lens 5 to emit light are individually arranged at both end faces of the light guide lens 5, that is, at positions facing the end face 51 a of the first straight part 51 and the end face 52 a of the second straight part 52. Yes. The light sources 6 and 6 are held by the housing 2 while being shielded from the front by extensions (not shown).

  Further, the light guide lens 5 is formed in a substantially quadrangular cross section, and has a plurality of prism cuts 50,... Formed on substantially the entire length, as shown in FIG. Each prism cut 50 is formed in a triangular prism shape that extends in the direction orthogonal to the longitudinal direction X of the light guide lens 5 (the width direction of the rear surface) and narrows backward in the longitudinal direction X. The prism cuts 50,... Are formed in a cross-sectional saw blade shape in which the prism cuts 50 are arranged along the longitudinal direction X. Further, the prism cuts 50,... Have a cut pitch P of 0.3 mm or less along the longitudinal direction X between the adjacent prism cuts 50, 50.

Moreover, as shown in FIG. 4, the extending portion 53 extending substantially along the vertical direction of the light guide lens 5 has a cross section orthogonal to the extending direction Xa formed in a substantially square shape. It has a front surface 53a, a rear surface 53b, a right side surface 53c, and a left side surface 53d.
Among these, the front surface 53 a and the rear surface 53 b are inclined in the same manner as the light guide lens 5 is inclined following the opening surface of the housing 2. However, the front surface 53a has a surface parallel to the opening surface of the housing 2, that is, a surface inclined rearward from the right side surface 53c side toward the left side surface 53d side as a reference surface F, and as the distance from the both side surfaces 53c, 53d increases. Thus, the reference surface F is formed in a convex shape that bulges forward so as to be separated from the reference surface F forward. The rear surface 53b is a part of the rear surface of the entire light guide lens 5 having the prism cuts 50,..., And the base surface (the surface from which the prism cuts 50,. ) Is substantially parallel to the reference plane F.
The right side surface 53c intersects the front surface 53a so that the internal angle θ1 formed with the reference surface F becomes an acute angle in a cross section orthogonal to the extending direction Xa, and is substantially along the front-rear direction in the present embodiment.
The left side surface 53d intersects the front surface 53a so that the internal angle θ2 formed with the reference surface F becomes an obtuse angle in a cross section orthogonal to the extending direction Xa.

Then, the light emission aspect of the light guide lens 5 is demonstrated.
In the vehicular lamp 1, when the two light sources 6 and 6 emit light, the light emitted from the light sources 6 and 6 enters the light guide lens 5 from the end surface 51a and the end surface 52a. The light that has entered the light guide lens 5 is guided in the longitudinal direction X by repeating internal reflection, and is reflected forward by the prism cuts 50 and emitted from the front surface. In this way, the front surface of the light guide lens 5 emits light over its entire length, thereby forming a sub-light distribution that emits light from the periphery of the vehicular lamp 1.

  At this time, in the extending portion 53 of the light guide lens 5, the left side surface 53d and the front surface 53a are arranged so that the internal angle θ2 formed by the left side surface 53d and the reference surface F becomes an obtuse angle in the cross section orthogonal to the extending direction Xa. In other words, since the inner angle formed by the left side surface 53d and the rear surface 53b (base surface) is an acute angle, a part of the light reflected by the prism cuts 50,. Is reflected forward by the left side surface 53d. Therefore, the amount of light emitted to the front side can be increased as compared with the conventional case where all the light reflected by the rear surface is emitted obliquely to the lamp side. Although illustration is omitted, an extension (not shown) whose surface is subjected to aluminum vapor deposition is opposed to the left side surface 53d, and a part of the light reflected by the rear surface 53b and transmitted through the left side surface 53d Reflected forward on the surface of the extension.

  Here, an example of the amount of light whose emission direction is changed by the left side surface 53d is shown. For example, when the extending portion 53 has the cross-sectional shape (unit of length: mm) shown in FIG. 5, light corresponding to 2.3 mm out of the total width 4.3 mm of the rear surface 53b is forwarded by the left side surface 53d. Therefore, the amount of the reflected light is 2.3 / 4.3 × 100 = 53.4%. That is, 53.4% of the light reflected by the rear surface 53b can be emitted to the front side by the left side surface 53d.

  Further, in the extending portion 53, as shown in FIG. 4, since the front surface 53a is formed in a convex shape with the reference surface F bulging forward, the prism cuts 50,. The light reflected obliquely toward the vehicle side is emitted while being diffused in the left-right direction by the front surface 53a, so that the light can be diffused widely to the front side.

  Further, in the extending portion 53, the right side surface 53c and the front surface 53a intersect so that the internal angle θ1 formed by the right side surface 53c and the reference surface F is an acute angle in a cross section orthogonal to the extending direction Xa. Unlike the conventional case where the extending portion is formed in a simple rectangular cross section, the right side surface 53c located on the front side with respect to the rear surface 53b is inclined so as to open to the front side. Therefore, the rear surface 53b, which is the reflection surface, can be viewed more widely when viewed from the front, compared to the conventional case where a part of the rear surface, which is the reflection surface, is shielded by the side surface on the front side.

  In the light guide lens 5, as shown in FIG. 3, the prism cut 50 that reflects light from the light source 6 forward is formed in a shape that narrows backward in the longitudinal direction X. Light that is guided in the lens 5 in the longitudinal direction X is less likely to enter the apex angle portion 50 a of the prism cut 50. Therefore, when the light guide lens 5 at the time of lighting is viewed from the front, each prism cut 50,... Has a dark portion near each apex portion 50 a, but the adjacent prism cuts 50,. Since the cut pitch P between 50 is 0.3 mm or less, as described below, it is not a lighting feeling that the dark part looks like a striped pattern, but a good lighting feeling with a uniform feeling is obtained. Can do.

Here, the effect of improving the lighting feeling by setting the cut pitch P to 0.3 mm or less will be described.
In setting the cut pitch P, the concept of visual acuity inspection using a C-shaped Landolt ring is applied. In the visual acuity test, the reciprocal of the minimum visual angle [minute] is defined as visual acuity, and a visual acuity of 1.0 (visual angle 1/60 [deg] ≈0.017 [deg] is obtained when a discontinuity width of 1.5 mm can be determined from a distance of 5 m. ]). Thus, the minimum cut width that a person with a visual acuity of 1.0 can discriminate from a distance of 1 m is (1.5 [mm] / 5 [m] × 1 [m] =) 0.3 mm.

According to this way of thinking, when a human with a visual acuity of 1.0 looks at the light guide lens 5 from a distance of 1 m, the minimum dark width that can be identified is 0.3 mm. However, since the width of the dark portion cannot be greater than or equal to the cut pitch P, if the cut pitch P is set to 0.3 mm or less, the actual width of the dark portion is smaller than this.
Therefore, by setting the cut pitch P to 0.3 mm or less, even when a person with a visual acuity of 1.0 looks at the light guide lens 5 from a distance of 1 m, it is formed near the apex portion 50a of the prism cut 50. Therefore, it is difficult to determine the dark portion to be obtained, and as a result, a good lighting feeling with a uniform feeling can be obtained. Moreover, practically, even a pedestrian walking by the side of the vehicle rarely sees the light guide lens 5 (vehicle lamp 1) from a short distance of 1 m, and the light guide lens 5 that is a lighting optical system. Then, since the dark part looks indistinct, if the cut pitch P is set to 0.3 mm or less, a good lighting feeling can be surely obtained.

  As described above, according to the light guide lens 5, since the inner angle θ1 formed by the right side surface 53c and the reference surface F is an acute angle, the rear surface 53b that is a reflection surface can be viewed more widely when viewed from the front. In addition, since the inner angle θ2 formed by the left side surface 53d and the reference surface F is an obtuse angle, the amount of light emitted to the front side can be increased, and the front surface 53a is formed in a convex shape so that the emitted light is emitted. Can be diffused widely to the front side. Therefore, even when the light guide lens 5 (the vehicular lamp 1) is disposed obliquely in the left-right direction, the extending portion 53 that extends in the vertical direction is made to extend forward with respect to the front. Bright light can be emitted. Thereby, when the light guide lens 5 is viewed from the front, the first straight portion 51, the second straight portion 52, and the extending portion 53 can realize a light emission mode without unevenness in luminance.

  Further, the prism cuts 50,... Formed in a shape constricted backward in the longitudinal direction X have a cut pitch P between the adjacent prism cuts 50, 50 of 0.3 mm or less. When 5 is viewed from the front, it is difficult to distinguish the dark part formed in the vicinity of the apex part 50a of the prism cut 50, and a good lighting feeling with a uniform feeling can be obtained.

  The embodiments to which the present invention can be applied are not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit of the present invention.

  For example, in the above embodiment, the vehicular lamp 1 is described as a headlamp mounted on the front left side of the vehicle. However, the vehicular lamp applicable to the present invention is a headlamp mounted on the front right side of the vehicle. Or a rear lamp mounted on the rear left side or right side of the vehicle. However, when the vehicular lamp to which the present invention is applicable is a headlamp mounted on the right side of the front portion of the vehicle, the vehicular lamp 1 has a shape reversed right and left with respect to the vehicular lamp 1 in the above embodiment, and the rear lamp In this case, the vehicle lamp in the case of a headlamp does not have the same directional relationship with the vehicle, and the front, rear, left and right are reversed.

DESCRIPTION OF SYMBOLS 1 Vehicle lamp 2 Housing 5 Light guide lens 50 Prism cut 50a Apex corner part P Cut pitch 51 1st linear part 51a End surface 52 2nd linear part 52a End surface 53 Extension part 53a Front surface F Reference surface 53b Rear surface 53c Right side surface (One side side)
θ1 Interior angle 53d Left side (the other side)
θ2 Interior angle Xa Extension direction X Longitudinal direction 6 Light source

Claims (5)

A plurality of prisms provided in a lamp chamber of a vehicular lamp and having a plurality of prism cuts on substantially the entire length on the rear surface while guiding light incident from both end surfaces in the longitudinal direction. In the light guide lens that is reflected by the cut and emitted from the front,
A straight portion extending substantially along the left-right direction;
Extending substantially along the vertical direction and having an extending portion connected to the linear portion and the end portion ;
The extending portion has the front surface, the rear surface, one side surface, and the other side surface, and a cross section perpendicular to the extending direction is formed in a substantially rectangular shape,
The front surface is a surface inclined from the one side surface toward the other side surface toward the rear of the vehicular lamp, and the reference surface is expanded forward so as to diffuse the emitted light in the left-right direction. It is formed in a raised convex shape,
It said rear surface, a base surface on which the plurality of prisms cut is formed is formed substantially parallel to the said reference plane Rutotomoni, narrowly formed than the width of the width of the reference plane,
The one side surface intersects the front surface so that an internal angle formed with the reference surface is an acute angle in a cross section orthogonal to the extending direction, and extends along the front-rear direction of the vehicular lamp and It is formed on the center side of our vehicle,
The other side surface is a cross section orthogonal to the extending direction so that a part of the light internally reflected by the rear surface is internally reflected forward and the other part of the light is transmitted. in, Ri interior angle formed between the reference plane Majiwa and the front so that the obtuse angle, and the light guide lens, characterized in that it is formed on the side of the vehicle side of the extending portion. Two straight portions extending in a direction substantially orthogonal to the vertical direction are connected to the upper and lower ends of the extended portion,
2. The light guide lens according to claim 1, wherein the front end surfaces of the two linear portions are the both end surfaces that allow light to enter the light guide lens. The plurality of prism cuts are:
Each prism cut formed in a shape constricted backward toward the longitudinal direction is arranged along the longitudinal direction,
The light guide lens according to claim 1 or 2, wherein a cut pitch between adjacent prism cuts is 0.3 mm or less . The light guide lens according to any one of claims 1 to 3,
Two light sources individually opposed to the both end faces of the light guide lens;
A housing that holds the light guide lens and the two light sources so that the light guide lens is disposed along the periphery of the opening, and the front surface is formed in an open shape.
A vehicular lamp characterized by comprising: 5. The light guide lens according to claim 4, further comprising a reflecting member that is disposed opposite to the other side surface of the light guide lens and reflects the light that is internally reflected at the rear surface and transmitted through the other side surface to the front side. Vehicle lamp.

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