Lamp unit

Abstract

Provided is a novel lamp unit that is capable of reducing glare while achieving light distribution of a desired brightness. The lamp unit 14 comprises a first optical system 22 that forms a first light distribution pattern, and a second optical system 24 that is provided adjacent to the first optical system and forms a second light distribution pattern. The first optical system 22 has a first lens 16a. The second optical system 24 has a second lens 16b that is provided integrally with the first lens 16a. The first lens 16a has a first incident surface 28a on which light emitted from a first light-emitting element impinges, and a first emission surface 28b from which light impinging from the first incident surface 28a is emitted. The second lens 16b has a second incident surface 30a on which light emitted from a second light-emitting element impinges, and a second emission surface 30b from which light impinging from the second incident surface 30a is emitted.

Description

Lighting unit

[0001] The present invention relates to a lighting unit, for example, a lighting unit used in a vehicle lamp.

[0002] Conventionally, there have been proposed lamp units in which a plurality of lighting units, each with a different light distribution pattern, are arranged in a line. For example, Patent Document 1 discloses a lamp unit in which a first low beam lighting unit, a second low beam lighting unit, and a high beam lighting unit are arranged in the same line. In this lamp unit, the lens units of each lighting unit are integrally formed.

[0003] WO 21 / 166533 Pamphlet

[0004] When multiple lens units are formed integrally, as in the lighting unit described above, if light that enters one lens unit exits another adjacent lens unit, it does not contribute to forming the desired light distribution pattern and is wasted or becomes glare.

[0005] The present invention has been made in view of the above circumstances, and one of its exemplary purposes is to provide a new lighting unit that can reduce glare while realizing a light distribution with a desired brightness.

[0006] In order to solve the above-mentioned problems, one aspect of the present invention provides a lamp unit including a first optical system that forms a first light distribution pattern and a second optical system that is disposed adjacent to the first optical system and forms a second light distribution pattern, wherein the first optical system includes a first lens. The second optical system includes a second lens that is integral with the first lens. The first lens has a first incident surface onto which light emitted from the first light-emitting element is incident and a first exit surface from which the light incident from the first incident surface exits. The second lens has a second incident surface onto which light emitted from the second light-emitting element is incident and a second exit surface from which the light incident from the second incident surface exits. The first incident surface has a suppression region disposed on its outer periphery that suppresses the light incident from the first incident surface from proceeding toward the second exit surface.

[0007] According to this aspect, light incident from the first entrance surface is prevented from exiting from the second exit surface, thereby reducing glare while achieving the desired brightness of the first light distribution pattern formed by the first optical system.

[0008] The suppression region may have a second radius of curvature smaller than the first radius of curvature of the central region located inward of the suppression region, such that light incident on the outer periphery of the first incident surface is refracted more toward the central region.

[0009] The first light exit surface has a third radius of curvature of an outer periphery from which light refracted in the suppression region exits, the third radius of curvature being larger than a fourth radius of curvature of a central region inside the outer periphery.

[0010] The outer periphery may have an annular surface perpendicular to the front direction of the first light emitting element.

[0011] The first optical system may include a first light-emitting element. The second optical system may include a second light-emitting element. The first light-emitting element and the second light-emitting element may be arranged so that their light-emitting surfaces face the front of the vehicle lamp. This allows for a compact and thin lamp unit to be realized.

[0012] The first optical system may be configured to form a low beam light distribution pattern as the first light distribution pattern, and the second optical system may be configured to form a high beam light distribution pattern as the second light distribution pattern.

[0013] Any combination of the above components, and conversion of the present invention between a manufacturing method, a lighting fixture or lighting device, a light emitting module, a light source, etc. are also valid aspects of the present invention.

[0014] According to the present invention, a new lighting unit can be realized that can reduce glare while realizing a light distribution with a desired brightness.

[0015] 7(a) is a front view of a vehicle equipped with a vehicle lamp according to the present embodiment. FIG. 7(b) is a front view of a lamp unit according to the present embodiment. FIG. 7(c) is a perspective view of the lamp unit according to the present embodiment. FIG. 7(d) is a cross-sectional view of the lamp unit shown in FIG. 2 taken along line A-A. FIG. 7(e) is an enlarged cross-sectional view of a main part of a first lens according to a reference example. FIG. 7(f) is an enlarged cross-sectional view of a main part of a first lens according to the present embodiment. FIG. 7(a) is a cross-sectional view showing a modified example of the first lens, and FIG. 7(b) is a front view of the first lens shown in FIG. 7(a).

[0016] The present invention will be described below based on preferred embodiments with reference to the drawings. The same or equivalent components, parts, and processes shown in each drawing will be given the same reference numerals, and redundant explanations will be omitted where appropriate. Furthermore, the embodiments are illustrative and do not limit the invention, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

[0017] Fig. 1 is a front view of a vehicle equipped with a vehicle lamp according to this embodiment. The vehicle 10 shown in Fig. 1 includes a left-side vehicle lamp 12L disposed on the left front side of the vehicle and a right-side vehicle lamp 12R disposed on the right front side of the vehicle. Each of the left-side vehicle lamp 12L and the right-side vehicle lamp 12R is equipped with a lamp unit 14.

[0018] Fig. 2 is a front view of the lamp unit according to this embodiment. Fig. 3 is a perspective view of the lamp unit according to this embodiment. Fig. 4 is a cross-sectional view of the lamp unit taken along line A-A in Fig. 2. The lamp unit 14 has a projection lens 16 that is circular when viewed from the front, a substrate 18, and semiconductor light-emitting elements 20a and 20b mounted on the substrate 18. Examples of the semiconductor light-emitting elements include an LED, an LD, and an EL element.

[0019] The lamp unit 14 includes a first optical system 22 that forms a first light distribution pattern, a second optical system 24 that is disposed adjacent to the first optical system and that forms a second light distribution pattern, and a third optical system 26 that forms a third light distribution pattern. The first optical system 22 includes a first lens 16a. The second optical system 24 includes a second lens 16b that is integral with the first lens 16a. The third optical system 26 includes a third lens 16c that is integral with the first lens 16a. The first lens 16a, the second lens 16b, and the third lens 16c are arranged to correspond to the vertices of a triangle. The first lens 16a, the second lens 16b, and the third lens 16c are integrally molded from a translucent material (e.g., a transparent resin such as acrylic or polycarbonate).

[0020] The first optical system 22 has a semiconductor light-emitting element 20a. The second optical system 24 has a semiconductor light-emitting element 20b. The third optical system 26 has a semiconductor light-emitting element (not shown). Each semiconductor light-emitting element is arranged to face the front of the vehicle lamp 12L (12R). This allows for a compact and thin lamp unit 14 to be realized.

[0021] The first optical system 22 is configured to form a part or all of a low-beam light distribution pattern as a first light distribution pattern. The second optical system 24 is configured to form a part or all of a high-beam light distribution pattern or a low-beam light distribution pattern as a second light distribution pattern. The third optical system 26 is configured to form a part or all of a high-beam light distribution pattern as a third light distribution pattern.

[0022] As a result, the lamp unit 14 according to this embodiment forms a low-beam light distribution pattern by turning on the semiconductor light-emitting elements of the first optical system 22 and the second optical system 24 and turning off the semiconductor light-emitting elements of the third optical system 26. Moreover, the lamp unit 14 forms a high-beam light distribution pattern by turning on the semiconductor light-emitting elements of the second optical system 24 and the third optical system 26 and turning off the semiconductor light-emitting elements of the first optical system 22.

[0023] The first lens 16a has a first incident surface 28a onto which light emitted from the semiconductor light emitting element 20a is incident and a first exit surface 28b from which the light incident from the first incident surface 28a exits. The second lens 16b has a second incident surface 30a onto which light emitted from the semiconductor light emitting element 20b is incident and a second exit surface 30b from which the light incident from the second incident surface 30a exits.

[0024] Fig. 5 is an enlarged cross-sectional view of a main portion of a first lens according to a reference example. The first lens 32 shown in Fig. 5 has an incident surface 32a that forms a single continuous optical surface. In the optical system 34 shown in Fig. 5, a portion of the light (light L) from the semiconductor light emitting element 20a that enters through the incident surface 32a does not exit through the exit surface 32b but instead exits through the exit surface 36b of the adjacent optical system 36. Because the light L' that exits through the exit surface 36b is not light controlled by the optical system 34, it does not contribute to the formation of a desired light distribution pattern and may also result in glare.

[0025] To prevent light L from exiting the exit surface 36b of the adjacent optical system 36, it is preferable to position the semiconductor light-emitting element 20a as far away from the incident surface 32a as possible so that the light L is incident at an angle close to perpendicular to the incident surface 32a. Furthermore, by positioning the semiconductor light-emitting element 20a farther from the first lens 16a, the maximum luminous intensity of the projected light distribution pattern increases. However, if the distance between the semiconductor light-emitting element 20a and the incident surface 32a is too long, the thickness of the lamp unit 14 increases. Therefore, the distance between the semiconductor light-emitting element 20a and the incident surface 32a must be kept within a certain range. Therefore, light L is incident at an angle to the incident surface 32a, particularly in the outer region of the incident surface 32a, and is emitted from the exit surface 32b in a diverging manner.

[0026] Therefore, as shown in Fig. 4, first incident surface 28a of first lens 16a according to this embodiment is provided with a suppression region R on the outer periphery, which suppresses light incident from first incident surface 28a from proceeding toward second exit surface 30b. Fig. 6 is an enlarged cross-sectional view of a main portion of the first lens according to this embodiment.

[0027] 6, light L from the semiconductor light emitting element 20a incident through the suppression region R of the first incident surface 28a is emitted from the first exit surface 28b without being emitted from the second exit surface 30b. This prevents light L incident through the first incident surface 28a from being emitted from the second exit surface 30b, thereby reducing glare while achieving the desired brightness of the first light distribution pattern formed by the first optical system 22. Furthermore, since the area of ​​the first exit surface 28b can be made substantially the same as the area of ​​the first incident surface 28a, the radial size of the first lens 16a can be reduced.

[0028] Next, the width of the suppression region R will be described. As shown in FIG. 6, when the first incident surface 28a including the suppression region R is a continuous single optical control surface, light L that enters outside of position P2 where light L″ exiting from the end P1 of the first exit surface 28b enters the first incident surface 28a exits from the second exit surface 30b and becomes glare, etc. (see FIG. 5). Therefore, the first lens 16a according to this embodiment needs to be shaped so that the region outside position P2 is the suppression region R. Specifically, the suppression region R has a second radius of curvature r2 that is smaller than the first radius of curvature r1 of the central region R′ inside the suppression region R. As a result, light that enters the outer periphery of the first incident surface 28a is refracted more toward the central region.

[0029] FIG. 7( a) is a cross-sectional view showing a modified example of the first lens, and FIG. 7( b) is a front view of the first lens shown in FIG. 7( a). The first lens 38 shown in FIG. 7( a) has a first incident surface 28a similar to that of the first lens 16a. On the other hand, the first exit surface 38b has a third radius of curvature r3 of the outer peripheral portion R1, from which light refracted in the suppression region R is emitted, which is larger than the fourth radius of curvature r4 of the central region R2 inside the outer peripheral portion R1. Specifically, the outer peripheral portion R1 of the first exit surface 38b of the first lens 38 has an annular surface perpendicular to the front direction of the semiconductor light emitting element 20a. The annular surface functions, for example, as an auxiliary optical surface. Furthermore, the annular shape is not limited to a circle or a square as long as it is a closed shape, but may also be an ellipse, rectangle, or polygon, or may be a curve with a discontinuous curvature.

[0030] Although the present invention has been described above with reference to the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and suitable combinations and substitutions of the configurations of the embodiments are also included in the present invention. Furthermore, it is possible to suitably rearrange the combinations and processing orders in the embodiments based on the knowledge of those skilled in the art, and to make modifications to the embodiments such as various design changes, and such modified embodiments are also included in the scope of the present invention.

[0031] This international application claims priority based on Japanese Patent Application No. 2023-146537, filed on September 8, 2023, the entire contents of which are incorporated herein by reference.

[0032] The above descriptions of specific embodiments of the present invention have been presented for purposes of illustration. They are not intended to be exhaustive or to limit the invention to the precise forms described. Numerous modifications and variations will be apparent to those skilled in the art in light of the above description.

[0033] 10 Vehicle, 12L Left-side vehicle lamp, 14 Lamp unit, 16 Projection lens, 16a First lens, 16b Second lens, 18 Substrate, 20a Semiconductor light-emitting element, 22 First optical system, 24 Second optical system, 28a First incident surface, 28b First exit surface, 30a Second incident surface, 30b Second exit surface, R Suppression area.

Claims

1. A lighting unit comprising: a first optical system that forms a first light distribution pattern; and a second optical system that is disposed adjacent to the first optical system and forms a second light distribution pattern, wherein the first optical system has a first lens, and the second optical system has a second lens that is disposed integrally with the first lens, the first lens has a first incident surface into which light emitted from a first light-emitting element is incident and a first exit surface from which the light incident from the first incident surface exits, the second lens has a second incident surface into which light emitted from a second light-emitting element is incident and a second exit surface from which the light incident from the second incident surface exits, and the first incident surface has a suppression region disposed on its outer periphery that suppresses the light incident from the first incident surface from proceeding toward the second exit surface.

2. The lamp unit according to claim 1, wherein the suppression area has a second radius of curvature smaller than a first radius of curvature of a central area located inside the suppression area.

3. A lighting unit as described in claim 2, characterized in that the first exit surface has a third radius of curvature of the outer periphery from which light refracted in the suppression area is emitted which is larger than a fourth radius of curvature of a central area inside the outer periphery.

4. The lamp unit according to claim 3, wherein the outer peripheral portion has an annular surface perpendicular to the front direction of the first light emitting element.

5. A lamp unit as described in any one of claims 1 to 4, characterized in that the first optical system has the first light-emitting element, the second optical system has the second light-emitting element, and the first light-emitting element and the second light-emitting element are arranged so that their light-emitting surfaces face the front of the vehicle lamp.

6. A lamp unit as described in claim 5, characterized in that the first optical system is configured to form a low beam light distribution pattern as the first light distribution pattern, and the second optical system is configured to form a high beam light distribution pattern as the second light distribution pattern.

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