US-12624813-B2 - Vehicle lamp

US12624813B2US 12624813 B2US12624813 B2US 12624813B2US-12624813-B2

Abstract

A vehicle lamp includes a light source that radially emits light beam diagonally upward toward front, a projection lens that projects light beam emitted from the light source toward a front of a vehicle, and a reflection optical system that reflects the light beam emitted from the light source toward the projection lens, wherein the reflection optical system has a first reflection surface and a second reflection surface that are located diagonally above and in front of the light source, the first reflection surface forms a surface that is curved in an outward convex shape in the vertical cross section to reflect the light beam toward the projection lens while condensing the light beam, and the second reflection surface forms a surface that is curved in an inward concave shape in the vertical cross section to reflect the light beam toward the projection lens while diffusing the light beam.

Inventors

Nao Kaneko
Shinya Kogure

Assignees

STANLEY ELECTRIC CO., LTD.

Dates

Publication Date: 20260512
Application Date: 20250602
Priority Date: 20240604

Claims (10)

1 . A vehicle lamp comprising: a light source configured to radially emit a light beam diagonally upward toward a front; a projection lens that is disposed in front of the light source and that is configured to project light beam emitted from the light source toward a front of a vehicle; and a reflection optical system that is disposed between the light source and the projection lens and that is configured to reflect the light beam emitted from the light source toward the projection lens, wherein the reflection optical system has a first reflection surface and a second reflection surface that are located diagonally above and in front of the light source, in a vertical cross section including an optical axis of the light beam emitted from the light source, the second reflection surface and the first reflection surface are arranged in this order toward the front of the light source, so that, among light beam emitted radially from the light source, a light beam in a central region including the optical axis enters the first reflection surface, and a light beam in an upper peripheral region above the central region enters the second reflection surface, the first reflection surface forms a surface that is curved in an outward convex shape in the vertical cross section to reflect the light beam in the central region toward the projection lens while condensing the light beam, and the second reflection surface forms a surface that is curved in an inward concave shape in the vertical cross section to reflect the light beam in the upper peripheral region toward the projection lens while diffusing the light beam.
2 . The vehicle lamp according to claim 1 , wherein a light distribution pattern obtained by superimposing a first light distribution pattern formed by the light beam in the central region and a second light distribution pattern formed by the light beam in the upper peripheral region is projected forward while being inverted upside down by the projection lens.
3 . The vehicle lamp according to claim 2 , wherein the second light distribution pattern has a larger irradiation range in an up-down direction than the first light distribution pattern, and the first light distribution pattern has a higher maximum luminous intensity than the second light distribution pattern.
4 . The vehicle lamp according to claim 1 , wherein the first reflection surface and the second reflection surface form a continuous surface.
5 . The vehicle lamp according to claim 1 , wherein the reflection optical system is constituted by a part of a light guide lens, the light guide lens has an incident surface that is located on a side facing the light source, the first reflection surface and the second reflection surface that are located diagonally upward in front of the light source, and an emission surface that is located on a side facing the projection lens, the light incident surface allows the light beam emitted from the light source to enter an inside of the light guiding lens, and the light emission surface emits the light beam guided inside the light guide lens to an outside of the light guide lens toward the projection lens.
6 . The vehicle lamp according to claim 5 , wherein the incident surface forms a surface that is inclined diagonally downward toward the front in the vertical cross section, and among the light beam radially emitted from the light source, the incident surface enters a light beam in a lower peripheral region below the central region into the inside of the light guide lens toward the emission surface.
7 . The vehicle lamp according to claim 6 , wherein a light distribution pattern in which a first light distribution pattern formed by the light beam in the central region, a second light distribution pattern formed by the light beam in the upper peripheral region, and a third light distribution pattern formed by the light beam in the lower peripheral region are superimposed is projected forward while being inverted upside down by the projection lens.
8 . The vehicle lamp according to claim 7 , wherein an irradiation range in an up-down direction is larger in order of the second light distribution pattern, the third light distribution pattern, and the first light distribution pattern, and a maximum luminous intensity is larger in order of the first light distribution pattern, the second light distribution pattern, and the third light distribution pattern.
9 . The vehicle lamp according to claim 5 , wherein a plurality of light sources are arranged in a width direction of the vehicle, the light guide lens has the incident surface, the first reflection surface, the second reflection surface, and the emission surface which are disposed corresponding to each of the light sources, the emission surface is provided continuously in a width direction of the light guide lens, and the light distribution pattern of the light beam projected by the projection lens is variably controlled while lighting of the plurality of light sources are switched.
10 . The vehicle lamp according to claim 1 , wherein a plurality of light sources are arranged in a width direction of the vehicle, the reflection optical system is disposed corresponding to each of the light sources, and the light distribution pattern of the light beam projected by the projection lens is variably controlled while lighting of the plurality of light sources are switched.

Description

CROSS-REFERENCE TO RELATED APPLICATION Priority is claimed on Japanese Patent Application No. 2024-090670, filed Jun. 4, 2024, the content of which is incorporated herein by reference. BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a vehicle lamp. Description of Related Art For example, vehicle lamps such as vehicle headlights (headlamps) emit light, which forms a low-beam light distribution pattern including a cutoff line at an upper end as a dipped beam (a low beam), toward the front of the vehicle. Alternatively, vehicle lamps such as vehicle headlights (headlamps) emit, as a driving beam (a high beam), light that forms a high-beam light distribution pattern above the low-beam light distribution pattern, toward the front of the vehicle. Meanwhile, in the field of vehicle lamps, development of an adaptive light distribution headlamp (ADB) that includes a plurality of light sources arranged in a vehicle width direction and a projection lens that projects light emitted from the plurality of light sources toward the front of the vehicle, and that variably controls a light distribution pattern of the light projected by the projection lens while lighting of the plurality of light sources is switched is underway (refer to, for example, Japanese Unexamined Patent Application, First Publication No. 2019-220404). The ADB is a technology that uses an onboard camera to recognize preceding vehicles, oncoming vehicles, pedestrians, and the like, and expands a driver's forward visibility at night without dazzling drivers or pedestrians in front. In addition, some vehicle lamps integrate a low-beam optical system and a high-beam optical system, and each of the light sources is installed on the same plane so that an emission axis of each light faces diagonally upward toward the front (for example, Japanese Patent Application Publication No. 2022-28514). SUMMARY OF THE INVENTION However, in the above-described conventional vehicle lamp, when light emitted from the light source diagonally upward toward the front is reflected by a reflection surface toward the projection lens located in the front, there is a problem that efficiency of capturing light passing near a focal point of the projection lens becomes poor, and a maximum luminous intensity of the high-beam light distribution pattern becomes insufficient. On the other hand, by reducing dimensions of a emission surface of a light guide lens in an up-down direction, a density of the light passing near the focal point of the projection lens increases, and the luminous intensity is improved, but the spread of the light projected by the projection lens in the up-down direction becomes insufficient. An aspect of the present invention provides a vehicle lamp capable of improving light utilization efficiency and obtaining a good light distribution pattern. An aspect of the present invention provides the following configuration. [1] A vehicle lamp includes a light source configured to radially emit a light beam diagonally upward toward the front, a projection lens that is disposed in front of the light source and that is configured to project light beam emitted from the light source toward a front of a vehicle, and a reflection optical system that is disposed between the light source and the projection lens and that is configured to reflect the light beam emitted from the light source toward the projection lens, wherein the reflection optical system has a first reflection surface and a second reflection surface that are located diagonally above and in front of the light source, in a vertical cross section including an optical axis of the light beam emitted from the light source, the second reflection surface and the first reflection surface are arranged in this order toward the front of the light source, so that, among the light beam radially emitted from the light source, a light beam in a central region including the optical axis enters the first reflection surface, and a light beam in an upper peripheral region above the central region enters the second reflection surface, the first reflection surface forms a surface that is curved in an outward convex shape in the vertical cross section to reflect the light beam in the central region toward the projection lens while condensing the light beam, and the second reflection surface forms a surface that is curved in an inward concave shape in the vertical cross section to reflect the light beam in the upper peripheral region toward the projection lens while diffusing the light beam.[2] In the vehicle lamp described in [1], a light distribution pattern obtained by superimposing a first light distribution pattern formed by the light beam in the central region and a second light distribution pattern formed by the light beam in the upper peripheral region may be projected forward while being inverted upside down by the projection lens.[3] In the vehicle lamp described in [2], the second light distr