Vehicular headlamp

• US 20050094414A1
• Filed: 11/03/2004
• Published: 05/05/2005
• Est. Priority Date: 11/04/2003
• Status: Active Grant

• Current Assignee: Koito Manufacturing Company Limited
• Original Assignee: Koito Manufacturing Company Limited
• Inventors: Ishida, Hiroyuki, Tatsukawa, Masashi, Sazuka, Kiyoshi
• Granted Patent: US 7,201,506 B2
• Time in Patent Office: Days
• US Class Current: 362/545
• CPC Class Codes: F21S 41/148 the main emission direction of the LED being perpendicular to the optical axis
• CPC Class Codes: F21S 41/151 arranged in one or more lines
• CPC Class Codes: F21S 41/155 Surface emitters, e.g. organic light emitting diodes [OLED]
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A plurality of lamp piece units constituting light sources by semiconductor light emitting elements are used as a first lamp piece unit which is lighted in a low beam mode. Additionally, a single lamp piece unit constituting a light source by an electric discharge bulb color temperature of emitted light of which is as high as that of the semiconductor light emitting element, is used as a second lamp piece unit, which is additionally lighted in a high beam mode. When the beam is switched from the low beam to the high beam, pale irradiated light from the first lamp piece unit is added with pale irradiated light from the second lamp piece unit to thereby provide an impression for the driver and/or passenger of unity in colors between the two lamp piece units.

Claims

1. A vehicular headlamp that is switchable between a low beam mode and a high beam mode, comprising:

a first lamp piece unit, comprising a plurality of lamp piece units each having a semiconductor light emitting element as its light source; and

a second lamp piece unit, comprising an electric discharge bulb as its light source,

wherein the first lamp piece unit is lighted in the low beam mode, and the first lamp piece unit and the second lamp piece unit are lighted substantially simultaneously in the high beam mode.

2. The vehicular headlamp according to claim 1, wherein the semiconductor light emitting element comprises a white light emitting diode for emitting light at a color temperature of about 4000 through 6500 K, and the electric discharge bulb comprises a metal halide bulb for emitting light at a color temperature of about 4000 through 6500 K.

3. The vehicular headlamp according to claim 1, wherein each of the lamp piece units of the first lamp piece unit includes a projecting lens and a reflector that reflects light from the semiconductor light emitting element in a front direction on a rear side of the projecting lens, wherein a reflecting face of the reflector is configured to converge light from the semiconductor light emitting element reflected by the reflecting face substantially to a vicinity of a focal point on a rear side of the projecting lens.

4. The vehicular headlamp according to claim 1, wherein the second lamp piece unit includes:

a reflector that reflects light from the electric discharge bulb in a front direction, and

a reflecting face of the reflector comprising a reference face formed by a paraboloid of revolution having a focal point substantially by a position of a light emitting portion of the electric discharge bulb.

5. The vehicular headlamp of claim 1, wherein said vehicle headlamp is inclinable in an up direction, a down direction, a left direction and a right direction.

6. The vehicular headlamp of claim 1, further comprising a support bracket that supports said first lamp piece unit via a plurality of support portions corresponding to said plurality of lamp piece units, wherein a heat sink portion extends from said plurality of support portions.

7. The vehicular headlamp of claim 6, wherein said heat sink portion comprises a plurality of heat fins.

8. The vehicular headlamp of claim 1, wherein an optical axis of said first lamp piece unit is directed downward by about 0.5 to 0.6 degrees.

9. The vehicular headlamp of claim 1, wherein a focal length of said first lamp piece unit is substantially shorter than a focal length of said second lamp piece unit.

10. The vehicular headlamp of claim 1, wherein said electric discharge bulb comprises a metal halide bulb.

11. The vehicular headlamp of claim 1, wherein said plurality of lamp piece units comprises a first group of said lamp piece units positioned above a second group of said lamp piece units, and said plurality of lamp piece units are positioned substantially next to said second lamp piece unit.

12. The vehicular headlamp of claim 1, wherein said first lamp piece unit and said second lamp piece unit generate a substantially same color.