Koito Manufacturing Company, Ltd.

Noriko Okada

Satoshi Yamamura

Michio Tsukamoto

Hidetada Tanaka

Motohiro Komatsu

A lighting unit is provided with a cutoff line forming member disposed between a projection lens and a first light source and having a tip edge positioned in a vicinity of a rear focal point of the projection lens. The cutoff line forming member is capable of shielding a part of a light reflected by a reflector, thereby forming a cutoff line of a light distribution pattern for a low beam. An additional reflector is capable of collecting a light emitted from a second light source in a vicinity of the rear focal point of the projection lens. The light emitted from the second light source is collected in the vicinity of the rear focal point of the projection lens in a state in which the tip edge of the cutoff line forming member and the rear focal point of the projection lens are relatively separated from each other, and a light distribution pattern for a high beam is thus formed.

Lighting unit

A lighting device for a vehicle has a light-emitting element disposed on an optical axis, a first reflection surface for reflecting light emitted from the light-emitting element in an outer radial direction of the optical axis, and a second reflection surface for reflecting the light reflected by the first reflection surface forward. A cross-sectional shape of the first reflection surface taken along a predetermined plane including the optical axis is an ellipse. The ellipse has a light-emitting center as a first focus and an axis line crossing the optical axis as a major axis. The second reflection surface is disposed between the first focus and a second focus of the ellipse. A cross-sectional shape of the second reflection surface taken along the predetermined plane is a parabola having the second focus of the ellipse as a focus and a point located forward of the focus as a vertex.

Lighting device for vehicle

A headlamp includes a light source, a first auxiliary reflector disposed below a reflector, and a plurality of second auxiliary reflectors disposed on a front side of the first auxiliary reflector at a predetermined interval along a vertical direction. The light source is a line light source extending in a width direction of a vehicle. A sectional shape of a reflecting surface of the first auxiliary reflector taken along a vertical plane that is parallel to the optical axis is a shape of a parabola having an axis line downwardly extending in the forward direction at a predetermined downward inclination angle. A sectional shape of a reflecting surface of each of the second auxiliary reflectors taken along the vertical plane has a shape of a substantially straight line downwardly extending in the forward direction at a downward inclination angle which is smaller than the predetermined downward inclination angle.

Vehicle headlamp

A distance from a center position of the light source to a rear focal point of a projection lens is smaller than a focal length of the projection lens. The light source is constituted by a line segment light source extended in a vehicle width direction. An opening portion is formed at a rear portion of a first reflector. A second reflector reflects light directed to a rear side from the light source to a front side to be proximate to an optical axis.

A projector-type vehicle headlamp includes a light source which is a line light source extending in a width direction of a vehicle, a reflector, a first auxiliary reflector disposed below the reflector, and a second auxiliary reflector disposed on a front side of the first auxiliary reflector. A sectional shape of a reflecting surface of the first auxiliary reflector taken along a vertical plane that is parallel to an optical axis is a shape of a parabola having an axis line downwardly extending in a forward direction a predetermined downward inclination angle with respect to the optical axis. A sectional shape of a reflecting surface of a second auxiliary reflector taken along the vertical plane is a straight line downwardly extending in a forward direction at a downward inclination angle which is smaller than the predetermined downward inclination angle.

A light source bulb is fixedly inserted into a lateral direction to the optical axis Ax at a position below an optical axis Ax. Accordingly, a region lateral to the optical axis Ax on a reflection surface of the reflector can be effectively utilized for light distribution control. Furthermore, a first additional reflector having a reflection surface of substantially-spheroidal shape whose first focal point is at a position coincident with the light source is disposed at a position above the optical axis Ax. A second additional reflectorhaving a reflection surface of a substantially-parabolic vertical cross-sectional profile whose focal point is coincident with a second focal point of the first additional reflector is disposed at a position below the optical axis. As a result, light from the light source is illuminated forward without passing through a projection lens.

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Shizuoka, Japan

Noriko Okada