Lighting device and headlight for vehicle

• US 10,203,081 B2
• Filed: 03/19/2018
• Issued: 02/12/2019
• Est. Priority Date: 06/05/2017
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Matsuda, Takashi, Kasano, Masahiro
• Primary Examiner(s): Bowman, Mary Ellen
• Application Number:
  US15/925,724
• Publication Number:
  US 20180347776A1
• Time in Patent Office: 330 Days
• CPC Class Codes: F21S 41/143 the main emission direction of the LED being parallel to the optical axis of the illuminating device
• CPC Class Codes: F21S 41/24 Light guides
• CPC Class Codes: F21S 41/255 Lenses with a front view of circular or truncated circular outline
• CPC Class Codes: F21S 41/26 Elongated lenses
• CPC Class Codes: F21S 41/27 Thick lenses
• CPC Class Codes: F21S 41/275 Lens surfaces, e.g. coatings or surface structures
• CPC Class Codes: F21S 41/285 Refractors, transparent cover plates, light guides or filters not provided in groups F21S41/24 - F21S41/2805
• CPC Class Codes: F21S 41/322 the reflector using total internal reflection
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: F21Y 2115/20 Electroluminescent [EL] light sources

Abstract

A small and thin lighting device with high efficiency and good design and a headlight for a vehicle. A lighting device includes a first lens taking light generated by a light emitting device and emitting the light, and a second lens taking an emitted light from the first lens and emitting the light, in which the second lens is an anamorphic lens in which curvatures are different in a vertical direction and a right and left direction and a center of a lens surface in the vertical direction of the second lens is positioned in an upper direction with respect to an optical axis of the first lens. A headlight for a vehicle including the plural lighting devices is forming a low beam light distribution by superimposing lights from respective lighting devices for irradiation of the center, right and left in a horizontal direction respectively.

Claims

1. A headlight for a vehicle comprising:

a plurality of lighting devices arranged in a right and left direction, each having a different distribution of light and each comprising;

a light emitting device;

a first lens taking light generated by the light emitting device and emitting the light; and

a second lens taking an emitted light from the first lens and emitting the light in a given direction,

wherein the first lens includes an incident port on which light generated by the light emitting device is incident, an emission port from which light incident on the incident port and passing through the inside of the first lens is emitted, and a side surface portion including a plurality of side wall surfaces provided between the incident port and the emission port,

the incident port of the first lens has a concave shape surrounding the light emitting device, having a first incident surface as a concave bottom surface and a second incident surface as a concave side surface,

the side surface portion includes a first reflective surface on which light incident on the second incident surface is reflected and a second reflective surface on which light incident on the first incident surface and light reflected on the first reflective surface are reflected, and

the second lens is an anamorphic lens in which curvatures are different in a vertical direction and a right and left direction, and includes a light incident part in the vertical direction formed in a convex shape and a light emission part, wherein the light incident part or the light emission part in the right and left direction is formed in a convex shape, a concave shape or a linear shape;

wherein the second lens is a thin lens in which a thickness in the right and left direction is smaller than a thickness in the vertical direction.

2. The headlight according to claim 1,

wherein a center line of a lens surface in the vertical direction of the second lens is positioned in an opposite direction to the second reflective surface of the first lens with respect to an optical axis of the first lens.

3. The headlight according to claim 2,

wherein the second lens is an anamorphic lens in which curvatures of an emission surface are different in the vertical direction and the right and left direction.

4. The headlight for the vehicle according to claim 1, comprising three of said lighting devices,

wherein centers of distributions of light in the three lighting devices are set to a center, right and left, respectively, with respect to a front center of the vehicle.

5. The headlight for the vehicle according to claim 1,

wherein at least one of said lighting devices has a comparatively small light distribution angle and another at least one of said lighting devices has a comparatively wide light distribution angle compared to each other.

6. The headlight for the vehicle according to claim 4,

wherein the lighting devices in which centers of distributions of light are set to the right and left are formed by decentering the light incident part and the emission surface of the respective second lens in a horizontal direction.

7. A headlight for a vehicle comprising:

a plurality of lighting devices arranged in a right and left direction, each having a different distribution of light and each comprising;

a light emitting device;

a first lens; and

a second lens arranged so that the first lens is between the second lens and the light emitting device,

wherein the first lens includes an incident port, an emission port, and a side surface portion including a plurality of side wall surfaces provided between the incident port and the emission port, wherein the incident port of the first lens has a concave shape surrounding the light emitting device, having a first incident surface as a concave bottom surface and a second incident surface as a concave side surface,

wherein the side surface portion includes a first reflective surface and a second reflective surface, and

wherein the second lens is a thin lens in which a thickness in the right and left direction is smaller than a thickness in the vertical direction and is an anamorphic lens in which curvatures are different in a vertical direction and a right and left directions, and includes a light incident part in the vertical direction formed in a convex shape and a light emission part, wherein the light incident part or the light emission part in the right and left direction is formed in a convex shape, a concave shape or a linear shape.