VEHICULAR HEADLAMP

• US 20150103551A1
• Filed: 10/06/2014
• Published: 04/16/2015
• Est. Priority Date: 10/11/2013
• Status: Abandoned Application

• Current Assignee: Koito Manufacturing Company Limited
• Original Assignee: Koito Manufacturing Company Limited
• Inventors: TANAKA, Hidetada
• Application Number:
  US14/506,823
• Publication Number:
  US 20150103551A1
• Time in Patent Office: Days
• US Class Current: 362/520
• 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 41/151 arranged in one or more lines
• CPC Class Codes: F21S 41/255 Lenses with a front view of circular or truncated circular outline
• CPC Class Codes: F21S 41/275 Lens surfaces, e.g. coatings or surface structures
• CPC Class Codes: F21S 45/43 using gas
• CPC Class Codes: F21W 2102/18 for overhead signs
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A direct projection type vehicular headlamp includes a projection lens having an incident surface and a light emission surface, and a semiconductor light source. A reference surface and a light control surface positioned below the reference surface are provided on the incident surface, and the light control surface is inclined forward with respect to the reference surface in a direction form an upper side to a lower side. The reference surface has a shape to emit from the light emission surface direct light from the semiconductor light source, which has passed through the reference surface and the light emission surface, as substantially parallel light, and the light control surface has a shape to project the direct light from the semiconductor light source, which has passed through the light control surface and the light emission surface, on an upper portion of a predetermined distribution pattern formed by the substantially parallel light.

Claims

1. A direct projection type vehicular headlamp comprising:

a projection lens having an incident surface and a light emission surface as a convex curved surface; and

a semiconductor light source provided near a rear focal point of the projection lens, wherein;

the projection lens emits direct light from the semiconductor light source as substantially parallel light in front of the headlamp to form a predetermined distribution pattern;

a reference surface and a light control surface positioned below the reference surface are provided on the incident surface of the projection lens, and the light control surface is inclined forward with respect to the reference surface in a direction form an upper side to a lower side;

the reference surface has a shape to emit from the light emission surface the direct light from the semiconductor light source, which has passed through the reference surface and the light emission surface, as the substantially parallel light; and

the light control surface has a shape to project the direct light from the semiconductor light source, which has passed through the light control surface and the light emission surface, on an upper portion of the predetermined distribution pattern.

2. The vehicular headlamp according to claim 1, wherein the predetermined light distribution patter is a high beam distribution pattern.

3. The vehicular headlamp according to claim 1, wherein:

the light control surface includes a plurality of planar surfaces extending in a left-right direction;

each of the plurality of planar surfaces is inclined forward with respect to the reference surface in the direction form the upper side to the lower side; and

the plurality of planar surfaces are arranged such that a lower planer surface of the plurality of planar surfaces has a larger inclination angle with respect to the reference surface.

4. The vehicular headlamp according to claim 1, wherein the semiconductor light source includes a plurality of light sources arranged in a left-right direction, and the semiconductor light source is positioned to a rear of the rear focal point of the projection lens.