Patent Description:
A conventional vehicular lamp emits, through a projection lens, light from a first light source so as to form a light distribution pattern for passing and emits, through the projection lens, light from a second light source so as to form a light distribution pattern for traveling.

As such a vehicular lamp, a vehicular lamp capable of forming the light distribution pattern for traveling so that part of the light distribution pattern for traveling may cross over a cutoff line in the light distribution pattern for passing is conceived (see <CIT>, for instance). In this vehicular lamp, an additional projection lens is so provided as to surround a projection lens, and a focus of the projection lens, a focus of an upper lens part of the additional projection lens, and a focus of a lower lens part of the additional projection lens are set in various positions. This vehicular lamp uses reflectors set correspondingly to the respective focuses to cause light from a first light source and light from a second light source to reflect from the reflectors and pass through the respective focuses, so as to form the light distribution pattern for passing and the light distribution pattern for traveling so that the light distribution pattern for traveling may cross over the cutoff line of the light distribution pattern for passing.

In the vehicular lamp as above, however, in order to form the light distribution pattern for traveling, which has a lower end portion overlapping an upper end portion of the light distribution pattern for passing, it is necessary to provide the additional projection lens around the projection lens while imparting different curved faces to the projection lens as well as the upper lens part and the lower lens part of the additional projection lens. Consequently, the above vehicular lamp includes a complicated and large-sized lens. In the above vehicular lamp, a space needs to be secured for optical paths of light passing through the respective focuses set in various positions, leading to general enlargement.

<CIT> discloses a headlight which comprises at least two light sources, a first optical unit acting on the light sources, a second optical unit and a light shielding unit set to be close to a light axis of the headlight, wherein the first optical unit comprises an upper optical processor and a lower optical processor. The second optical unit comprises an upper unit and a lower unit. The upper unit comprises a first focus remote from the light shielding unit. The lower unit comprises a second focus close to the light shielding unit. First light rays from the first light source are projected to the lower unit via the second focus through the upper optical processor. Second light rays from the second light source are projected to the upper unit via the first focus through the lower optical processor; and the first focus and the second focus are located on the light axis.

Under such circumstances, we have appreciated that it would be desirable to provide a vehicular lamp that forms a light distribution pattern for traveling having a lower end portion overlapping an upper end portion of a light distribution pattern for passing and is downsized with a simple configuration.

The invention is defined in the independent claim to which reference should now be made.

A vehicular lamp according to claim <NUM> includes a projection lens projecting light emitted from a first light source to form a light distribution pattern for passing and project light emitted from a second light source to form a light distribution pattern for traveling, a lower lens part and an upper lens part are set in the projection lens about a lens axis as a center, a lower focus is set on the lens axis in the lower lens part, and an upper focus shorter in focal length than the lower focus is set on the lens axis in the upper lens part, wherein a gradual change lens part joining the lower lens part and the upper lens part is set in the projection lens, and the gradual change lens part continuously changes a focal length from the lower focus to the upper focus.

According to the vehicular lamp of the present disclosure, it is possible to form a light distribution pattern for traveling having a lower end portion overlapping an upper end portion of a light distribution pattern for passing and, at the same time, achieve the downsizing with a simple configuration.

In the following, examples of a vehicular lamp according to the present invention are described with reference to the drawings.

Using <FIG>, the vehicular lamp <NUM> of Example <NUM> as an embodiment of the vehicular lamp is described. The vehicular lamp <NUM> of Example <NUM> is used as a lamp for a vehicle such as an automobile, and used for a headlamp or a fog lamp, for instance. The vehicular lamp <NUM> is arranged on both the right and left sides of a front portion of a vehicle and provided, through an optical axis adjustment mechanism in vertical direction or an optical axis adjustment mechanism in lateral direction, in a lamp chamber formed by covering an opened front end of a lamp housing with an outer lens. In the following description, with respect to the vehicular lamp <NUM>, the direction of travel of a vehicle traveling straightforward, namely, the direction, in which light is emitted, is referred to as an optical axis direction (represented by Z in the drawings), the up and down direction in a state of being installed in a vehicle is referred to as a vertical direction (represented by Y in the drawings), and the direction, which is orthogonal to the optical axis direction and the vertical direction, is referred to as a width direction (represented by X in the drawings).

As illustrated in <FIG>, the vehicular lamp <NUM> includes a first light source <NUM>, a second light source <NUM>, a heat radiating member <NUM>, a first reflector <NUM>, a second reflector <NUM>, a shade <NUM>, and a projection lens <NUM>, and constitutes a headlight unit of a projector type.

The first light source <NUM> is constituted of a light emitting element such as an LED (light emitting diode) and implemented on a board <NUM>. The board <NUM> is fixed to an upper face 13a of the heat radiating member <NUM>. The first light source <NUM> has an optical axis of light emission (optical axis direction) substantially coincident with the vertical direction, and is appropriately turned on by the feed of power from a lighting control circuit.

The second light source <NUM> is constituted of a light emitting element such as an LED and implemented on the board <NUM> ahead of the first light source <NUM> in the optical axis direction. Consequently, the second light source <NUM> is in the same plane with the first light source <NUM>. The second light source <NUM> has an optical axis of light emission (optical axis direction) substantially coincident with the vertical direction, and is appropriately turned on by the feed of power from the lighting control circuit. The second light source <NUM> in Example <NUM> is constituted of a plurality of light source parts 12a (one light source part nearest to a viewer being only illustrated in <FIG>) aligned on the board <NUM> in the width direction. The light source parts 12a are each constituted of a light emitting element, and are appropriately turned on in a simultaneous or individual manner by the feed of power from the lighting control circuit.

The heat radiating member <NUM> is a heat sink member for releasing heat generated in the first light source <NUM> and the second light source <NUM> outside, and is formed of die-cast aluminum or a resin having heat conductivity and appropriately provided with a plurality of heat radiating fins, with an upper face 13a being made to be a flat face orthogonal to the vertical direction. On the upper face 13a of such heat radiating member <NUM>, the board <NUM> is provided, and the first reflector <NUM> and the second reflector <NUM> are provided on the upper face 13a correspondingly to the first light source <NUM> and the second light source <NUM> on the board <NUM>, respectively. The upper face 13a of the heat radiating member <NUM> in Example <NUM> is provided below a lens axis La of the projection lens <NUM> in the vertical direction.

The first reflector <NUM> covers the first light source <NUM> and the second reflector <NUM> and has a first reflective face <NUM> opposite to the first light source <NUM>. The first reflective face <NUM> reflects light emitted from the first light source <NUM> toward the projection lens <NUM>. The first reflective face <NUM> is formed by adhering a reflective material, such as aluminum and silver, onto an inner face of the first reflector <NUM> opposite to the first light source <NUM> by vapor deposition, application or the like. The first reflective face <NUM> in Example <NUM> has a lower reflective face part 21a on a base side of the first reflector <NUM> and an upper reflective face part 21b continuously extending from the lower reflective face part 21a upward. The lower reflective face part 21a is provided below an upper edge of the second reflector <NUM> (the lens axis La) in the vertical direction, is assumed as a free-form surface based on an ellipse having a focus at the first light source <NUM>, and reflects the light emitted from the first light source <NUM> toward an upper lens part <NUM> set in an upper portion of the projection lens <NUM>. The upper reflective face part 21b is assumed as a free-form surface based on an ellipse having a first focus at the first light source <NUM> and a second focus in the vicinity of a front edge portion 16a of the shade <NUM> (a lower focus Fd of a lower lens part <NUM>), and reflects the light emitted from the first light source <NUM> toward the lower focus Fd.

The second reflector <NUM> is provided ahead of the first light source <NUM> but behind two focuses (the lower focus Fd and an upper focus Fu) of the projection lens <NUM> in the optical axis direction inside the first reflective face <NUM> and below the lens axis La in the vertical direction. The second reflector <NUM> covers the second light source <NUM> and has a second reflective face <NUM> opposite to the second light source <NUM>. The second reflective face <NUM> reflects light emitted from the second light source <NUM> toward the upper lens part <NUM> set in the upper portion of the projection lens <NUM>. The second reflective face <NUM> is formed by adhering a reflective material, such as aluminum and silver, onto an inner face of the second reflector <NUM> opposite to the second light source <NUM> by vapor deposition, application or the like. The second reflective face <NUM> is assumed as a free-form surface based on an ellipse having a first focus at the second light source <NUM> and a second focus in the vicinity of the upper focus Fu of the upper lens part <NUM>, which is set on the lens axis La, and reflects the light emitted from the second light source <NUM> toward the upper focus Fu. The second reflector <NUM> is not limited to the configuration in Example <NUM> but may be provided ahead of the first reflective face <NUM>.

The shade <NUM> blocks part of the light emitted from the first light source <NUM>, so as to form a cutoff line Cl of a light distribution pattern LP for passing (see <FIG> and so forth). The shade <NUM> is in the form of a plate extending in the width direction and has the shape, in which two horizontal edges at different heights are joined by a tilted edge. The shade <NUM> is arranged so that the front edge portion 16a may be located at or near the lower focus Fd of the projection lens <NUM>. The shade <NUM> forms the cutoff line Cl, which is constituted of two horizontal lines joined by a tilted line, at an upper edge of the light distribution pattern LP for passing by blocking, with the front edge portion 16a, part of the light as emitted from the first light source <NUM> and reflected by the first reflective face <NUM> of the first reflector <NUM>. The shade <NUM> blocks light at a horizontal plane including the lens axis La, that is to say, prevents light from passing through the horizontal plane in the vertical direction at least between the lower focus Fd and the second reflector <NUM> (a front end thereof).

The projection lens <NUM> projects, toward the front of a vehicle, the light as emitted from the first light source <NUM> and reflected by the first reflector <NUM> (the first reflective face <NUM> thereof), so as to form the light distribution pattern LP for passing (see <FIG> and so forth). In addition, the projection lens <NUM> projects, toward the front of the vehicle, the light as emitted from the second light source <NUM> and reflected by the second reflector <NUM> (the second reflective face <NUM> thereof), so as to form a light distribution pattern HP for traveling (see <FIG> and so forth). The projection lens <NUM> is fitted to the heat radiating member <NUM> through a lens holder in the state of being positioned with respect to the first light source <NUM>, the second light source <NUM>, the first reflector <NUM>, the second reflector <NUM>, and the shade <NUM>.

The projection lens <NUM> is in the form of a convex lens that is circular as viewed from the front in the optical axis direction, and it is assumed in Example <NUM> that a light exit face 17a is a convex face and a light entrance face 17b is a flat face. The projection lens <NUM> is not limited to the configuration in Example <NUM>, and the light exit face 17a may be a flat face or a concave face and the light entrance face 17b may be a convex face or a concave face as long as the projection lens <NUM> is a convex lens as a whole. The projection lens <NUM> has the lens axis La, which extends in the optical axis direction. The lens axis La is an optical axis passing through the position in the projection lens <NUM>, where the thickness in the optical axis direction is largest, and the direction, in which the lens axis La extends, is made parallel to (coincident with) the optical axis direction.

Next using <FIG>, a detailed configuration of the projection lens <NUM> is described. On a vertical axis in <FIG>, a focal length Df as a distance from a principal point to a focus on a back side in the optical axis direction in the projection lens <NUM> is shown. Assuming a portion under the lens axis La of a vertical plane including the lens axis La as a reference plane Br, an angle θ in a rotational direction about the lens axis La as a center of rotation (zero degrees at the reference plane Br), with a counterclockwise side being a positive side and a clockwise side being a negative side, is shown on a horizontal axis in <FIG>.

As illustrated in <FIG>, the projection lens <NUM> is divided in the rotational direction about the lens axis La as a center of rotation so as to set the lower lens part <NUM> located on a lower side, the upper lens part <NUM> located on an upper side, and two gradual change lens parts <NUM> joining the lower lens part <NUM> and the upper lens part <NUM>. The projection lens <NUM> is plane-symmetrically formed with respect to the vertical plane including the lens axis La, with the lens parts (<NUM>, <NUM>, and <NUM>) each having an angular range (the absolute value of the angle θ in <FIG>) with respect to the reference plane Br (vertical plane) that is made equal on the right and left, and the two gradual change lens parts <NUM> make a pair in the width direction. The lens parts (<NUM>, <NUM>, and <NUM>) are made different from one another in the curvature of the light exit face 17a in a cross section extending from the lens axis La in a radial direction, and made different from one another in the focal length Df. In other words, in the projection lens <NUM>, different focal lengths Df are set according to the angular range in the rotational direction about the lens axis La while the lens axis La is shared.

The lower lens part <NUM> forms the light distribution pattern LP for passing (at least part thereof) in <FIG> by projecting, toward the front of the vehicle, the light as emitted from the first light source <NUM> and reflected by the first reflector <NUM> (the first reflective face <NUM> thereof). As illustrated in <FIG> and <FIG>, in the lower lens part <NUM>, the lower focus Fd as a focus on the back side in the optical axis direction is set in a position on the lens axis La that gives a focal length Df1, and arranged in the vicinity of the front edge portion 16a of the shade <NUM>.

The upper lens part <NUM> forms the light distribution pattern HP for traveling in <FIG> by projecting, toward the front of the vehicle, the light as emitted from the second light source <NUM> and reflected by the second reflector <NUM> (the second reflective face <NUM> thereof). In the upper lens part <NUM>, the upper focus Fu as a focus on the back side in the optical axis direction is set in a position on the lens axis La that gives a focal length Df2. The upper lens part <NUM> in Example <NUM> is made to have the focal length Df2, which is shorter than the focal length Df1, by setting the curvature of the light exit face 17a to be larger than the curvature of the light exit face 17a in the lower lens part <NUM> (line illustrated above the lens axis La in <FIG> with a long-dashed double-dotted line). The upper focus Fu (the focal length Df2) is appropriately set on the basis of the lower focus Fd. It is also possible to set the lower focus Fd on the basis of the upper focus Fu.

Each gradual change lens part <NUM> joins the lower lens part <NUM> and the upper lens part <NUM>, which are made different in the focal length Df from each other, and continuously changes (that is to say, makes a so-called gradual change of) the focal length Df from the lower focus Fd on the lower lens part <NUM> side to the upper focus Fu on the upper lens part <NUM> side. In other words, each gradual change lens part <NUM> continuously changes the focal length Df so that the focal length Df may be the focal length Df1 in the angular position about the lens axis La as a center of rotation, where the relevant gradual change lens part <NUM> is in contact with the lower lens part <NUM>, and the focal length Df2 in the angular position, where the relevant gradual change lens part <NUM> is in contact with the upper lens part <NUM> (see <FIG>). Therefore, each gradual change lens part <NUM> is so formed as to change the focal length Df according to the angular position and, at the same time, have a focus (point where a parallel light is condensed) on the lens axis La in any angular position.

In the projection lens <NUM> in Example <NUM>, the lower lens part <NUM> occupies an angular range from zero degrees to <NUM> degrees on an absolute value basis, the upper lens part <NUM> occupies an angular range from <NUM> degrees to <NUM> degrees on an absolute value basis, and the two gradual change lens parts <NUM> each occupy an angular range from <NUM> degrees to <NUM> degrees on an absolute value basis. In the projection lens <NUM>, moreover, the focal length Df is of an equal value in angular positions where an angle on the positive side measured counterclockwise from the reference plane Br and an angle on the negative side measured clockwise from the reference plane Br are equal to each other on an absolute value basis, and as such has a value between the focal length Df1 and the focal length Df2. The angular ranges of the lower lens part <NUM>, the upper lens part <NUM>, and the two gradual change lens parts <NUM> are not limited to the configuration in Example <NUM> but may be set as appropriate or made different between the right and the left.

Next, the lighting of the vehicular lamp <NUM> is described. The vehicular lamp <NUM> is provided in the lamp chamber, and an external connector is connected to the board <NUM> through a connector joint. In the vehicular lamp <NUM>, the first light source <NUM> and the second light source <NUM> implemented on the board <NUM> are appropriately turned on and off by the feed of power from the lighting control circuit to the first light source <NUM> and the second light source <NUM> through the external connector and the connector joint.

As illustrated in <FIG>, in the vehicular lamp <NUM>, light from the first light source <NUM> as turned on is reflected by the upper reflective face part 21b of the first reflective face <NUM> of the first reflector <NUM> so as to cause the light to travel into the vicinity of the lower focus Fd of the lower lens part <NUM> of the projection lens <NUM>, which focus is set on the lens axis La in the vicinity of the front edge portion 16a of the shade <NUM>. The light is partially blocked by the front edge portion 16a and is given a shape along the front edge portion 16a, then travels to the lower lens part <NUM> and is projected by the lower lens part <NUM> (the projection lens <NUM>) so as to form the light distribution pattern LP for passing in <FIG>, which has the cutoff line Cl at the upper edge.

The vehicular lamp <NUM> includes the shade <NUM>, which is provided at least between the lower focus Fd of the lower lens part <NUM> and the front end of the second reflector <NUM>, and light is blocked at the horizontal plane including the lens axis La between the lower focus Fd and the front end of the second reflector <NUM>. Consequently, in the vehicular lamp <NUM>, it is possible to cause the light as emitted from the first light source <NUM> and reflected by the upper reflective face part 21b to travel above the front edge portion 16a of the shade <NUM> in a lower focus plane including the lower focus Fd (image plane) and enter the lower lens part <NUM>. As a result, in the vehicular lamp <NUM>, it is possible to prevent the light as reflected by the upper reflective face part 21b from being projected into an unwanted position in a region (above a position (horizontal line) of the lens axis La in a projection plane) where the light distribution pattern HP for traveling in <FIG> is formed.

In the vehicular lamp <NUM>, the light from the first light source <NUM> as turned on is reflected by the lower reflective face part 21a of the first reflective face <NUM> of the first reflector <NUM> so as to cause the light to travel above the shade <NUM> to the upper lens part <NUM> of the projection lens <NUM>. The light is projected by the upper lens part <NUM> (the projection lens <NUM>) so as to irradiate and illuminate an optional position in the light distribution pattern LP for passing in <FIG> with the light.

In the vehicular lamp <NUM>, the lower reflective face part 21a is provided below the upper edge of the second reflector <NUM> in the vertical direction, so that it is possible to cause the light as emitted from the first light source <NUM> and reflected by the lower reflective face part 21a to travel above the lens axis La in an upper focus plane including the upper focus Fu (image plane) and enter the upper lens part <NUM>. As a result, in the vehicular lamp <NUM>, it is possible to prevent the light as reflected by the lower reflective face part 21a from being projected into an unwanted position in a region where the light distribution pattern HP for traveling is formed. Thus in the vehicular lamp <NUM>, the light distribution pattern LP for passing is appropriately formed.

In addition, in the vehicular lamp <NUM>, light from the second light source <NUM> as turned on is reflected by the second reflective face <NUM> of the second reflector <NUM> so as to cause the light to travel into the vicinity of the upper focus Fu of the upper lens part <NUM> of the projection lens <NUM>, which focus is set on the lens axis La. The light travels to the upper lens part <NUM> and is projected by the upper lens part <NUM> (the projection lens <NUM>) so as to form the light distribution pattern HP for traveling (see <FIG>). In the vehicular lamp <NUM>, the upper focus Fu is so set on the lens axis La as to be closer to the projection lens <NUM> (that is to say, as to be of a shorter focal length Df) than the lower focus Fd set in the vicinity of the front edge portion 16a of the shade <NUM>. Consequently, in the vehicular lamp <NUM>, light is not blocked by the shade <NUM> in the vicinity of the upper focus Fu, so that it is possible to cause the light from the second light source <NUM> to travel not only below the upper focus Fu in a focal plane including the upper focus Fu (image plane) but above the upper focus Fu in the same focal plane to the upper lens part <NUM>. Thus in the vehicular lamp <NUM>, as illustrated in <FIG>, it is possible to arrange a lower edge of the light distribution pattern HP for traveling below the position (horizontal line) of the lens axis La in the projection plane even if part of the light from the second light source <NUM> is blocked by the front edge portion 16a of the shade <NUM> and the lower edge is given a shape along the front edge portion 16a. Therefore in the vehicular lamp <NUM>, as illustrated in <FIG>, the light distribution pattern HP for traveling is formed with the light from the second light source <NUM> so that a lower end portion of the light distribution pattern HP for traveling may overlap an upper end portion of the light distribution pattern LP for passing.

The vehicular lamp <NUM> of Example <NUM> may be an ADB (adaptive driving beam (adaptive headlight)). In that case, if the light source parts 12a of the second light source <NUM> in the vehicular lamp <NUM> are turned on, light from each light source part 12a forms a light distribution portion obtained by dividing the light distribution pattern HP for traveling in the width direction. In the vehicular lamp <NUM> in that case, a light distribution portion in a specified direction can be extinguished among a plurality of light distribution portions by individually turning on and off the light source parts 12a. Thus in the vehicular lamp <NUM> in that case, a partial extinguishment in an optional direction in the light distribution pattern HP for traveling is allowed by individually turning on and off the light source parts 12a.

Therefore, in the vehicular lamp <NUM>, the light distribution pattern LP for passing having the cutoff line Cl is formed as illustrated in <FIG> by turning on the first light source <NUM>, so as to achieve the light distribution during the passing (as so-called low beams). Further, in the vehicular lamp <NUM>, the light distribution pattern HP for traveling, which partially overlaps the light distribution pattern LP for passing, is formed as illustrated in <FIG> by turning on not only the first light source <NUM> but the second light source <NUM>, so as to achieve the light distribution during the traveling (as so-called high beams). In the vehicular lamp <NUM>, moreover, it is also possible to turn off a light source part 12a located in an optional direction among the light source parts 12a of the second light source <NUM>, as described above, so as not to form only a light distribution portion in the corresponding direction and thereby exert a function of the ADB.

Next, operations of the vehicular lamp <NUM> are described. First of all, description is made on a conventional, general vehicular lamp (hereinafter referred to as a conventional vehicular lamp) for comparison with the vehicular lamp <NUM>. The conventional vehicular lamp is the same in configuration as the vehicular lamp <NUM> of Example <NUM> except that a focus on the back side in the optical axis direction of the projection lens <NUM> is only set at one place corresponding to the lower focus Fd in the vicinity of the front edge portion 16a of the shade <NUM>. Therefore, in order to facilitate understanding, the following description is made using the same names and reference signs as the vehicular lamp <NUM>.

In the conventional vehicular lamp, light traveling from the first light source <NUM> via the first reflector <NUM> and light traveling from the second light source <NUM> via the second reflector <NUM> are caused to enter the projection lens <NUM> via the vicinity of the lower focus Fd. Consequently, in the conventional vehicular lamp, the light distribution pattern LP for passing having the cutoff line Cl at the upper edge is formed by blocking part of the light from the first light source <NUM> by the shade <NUM>, as is the case with the vehicular lamp <NUM>. In the conventional vehicular lamp, however, it is not possible to cause the light from the second light source <NUM> to travel above the lower focus Fd in the lower focus plane including the lower focus Fd (image plane) and enter the projection lens <NUM> because the front edge portion 16a of the shade <NUM> is located in the vicinity of the lower focus Fd. As a result, if, in the conventional vehicular lamp, part of the light form the second light source <NUM> is blocked by the front edge portion 16a of the shade <NUM> and the lower edge of the light distribution pattern HP for traveling is given a shape along the front edge portion 16a, the lower edge is located above the position (horizontal line) of the lens axis La in the projection plane, as illustrated in <FIG>. Thus in the conventional vehicular lamp, a gap due to the front edge portion 16a is formed between the upper end portion of the light distribution pattern LP for passing formed with the light from the first light source <NUM> and the lower end portion of the light distribution pattern HP for traveling formed with the light from the second light source <NUM>.

In contrast, in the vehicular lamp <NUM> of Example <NUM>, the lower focus Fd of the lower lens part <NUM> is set in the vicinity of the front edge portion 16a of the shade <NUM> and the upper focus Fu of the upper lens part <NUM> is set closer to the projection lens <NUM> (that is to say, set to be of a shorter focal length Df) than the lower focus Fd, on the lens axis La of the projection lens <NUM>. Thus in the vehicular lamp <NUM>, it is possible to partially block the light traveling from the first light source <NUM> via the first reflector <NUM> by the shade <NUM> and cause the light to travel to the lower lens part <NUM>, and to cause the light traveling from the second light source <NUM> via the second reflector <NUM> to travel not only below the upper focus Fu but above the upper focus Fu to the upper lens part <NUM>. As a result, in the vehicular lamp <NUM>, the light distribution pattern LP for passing is appropriately formed and the light distribution pattern HP for traveling having the lower end portion overlapping the upper end portion of the light distribution pattern LP for passing is appropriately formed.

In the projection lens <NUM> of the vehicular lamp <NUM>, the lower focus Fd of the lower lens part <NUM> located on the lower side and the upper focus Fu of the upper lens part <NUM> located on the upper side are set on the lens axis La by changing the curvature of the light exit face 17a in a cross section extending from the lens axis La in the radial direction. Consequently, in the vehicular lamp <NUM>, the projection lens <NUM> is made simpler in configuration and smaller as compared with the aforementioned technology in the prior art document (hereinafter simply referred to as prior art), in which an additional projection lens is so provided as to surround a projection lens. As a result, in the vehicular lamp <NUM>, the number of parts is reduced, the cost of molds for lens formation is suppressed, and the manufacturing cost is suppressed as compared with the prior art. In addition, in the vehicular lamp <NUM>, the light from the first light source <NUM> and the light from the second light source <NUM> are caused to enter the projection lens <NUM> via the vicinity of the lower focus Fd and the upper focus Fu on the lens axis La. As a result, in the vehicular lamp <NUM>, it is possible to reduce the space, where optical paths for guiding the light from the first light source <NUM> and the light from the second light source <NUM> to the projection lens <NUM> are to be provided, as compared with the prior art, in which a plurality of focuses are set in various positions. As seen from such facts, the vehicular lamp <NUM> is able to be downsized with a simple configuration as compared with the prior art.

In the projection lens <NUM> of the vehicular lamp <NUM>, not only the lower lens part <NUM> and the upper lens part <NUM> but the gradual change lens parts <NUM>, each of which continuously changes the focal length Df from the lower focus Fd of the lower lens part <NUM> to the upper focus Fu of the upper lens part <NUM>, are provided. Consequently, in the vehicular lamp <NUM>, it is possible to produce the light exit face 17a of the projection lens <NUM> as a single, smooth and stepless face and appropriately form the light distribution pattern LP for passing and the light distribution pattern HP for traveling, which partially overlap each other.

Generally, in a projection lens, the lower lens part <NUM> and the upper lens part <NUM>, which are provided without providing the gradual change lens parts <NUM>, are made different in the curvature of the light exit face 17a from each other in order to set different focal lengths Df. As a result, in the light exit face 17a of the projection lens, a step is formed in a position of boundary between the lower lens part <NUM> and the upper lens part <NUM>. Since the position of boundary is on the lens axis La, the step may form an unintended bright region on the periphery of the position of the lens axis La in the projection plane (see a position indicated by a region A enclosed with a broken line in <FIG>) separately from the light distribution pattern LP for passing. Such a bright region dazzles a person on an oncoming vehicle and is, accordingly, not appropriate to the case of forming the light distribution pattern LP for passing, and makes the light distribution pattern HP for traveling unintended in the case of forming the light distribution pattern HP for traveling.

In contrast, in the projection lens <NUM> in the vehicular lamp <NUM> of Example <NUM>, the lower lens part <NUM> and the upper lens part <NUM> are joined by the gradual change lens parts <NUM>, each of which changes the focal length Df according to the angular position. As a result, the projection lens <NUM> of the vehicular lamp <NUM> has the light exit face 17a, which is made stepless and smooth, and has a focus on a lens axis La in any angular position. Thus, each of the gradual change lens parts <NUM>, as bringing about a stepless and smooth face, improves the appearance of the light exit face 17a and prevents the irradiation of an unintended position in the projection plane from being caused by a step, and allows the irradiation of an intended position in the projection plane by always having a focus irrespective of the angular position. In the vehicular lamp <NUM>, it is therefore possible to make the light distribution pattern LP for passing and the light distribution pattern HP for traveling appropriate as intended by providing the gradual change lens parts <NUM> apart from the lower lens part <NUM> and the upper lens part <NUM>.

In the vehicular lamp <NUM> of Example <NUM>, the first light source <NUM> and the second light source <NUM> are attached to the upper face 13a in a flat shape through the board <NUM> and arranged in one and the same plane. Generally, in a heat sink, heat is radially transferred from a heat source, so that it is possible to improve the cooling performance by securing a section that is increased in volume in the form of a concentric sphere centering at the heat source. In the vehicular lamp <NUM> of Example <NUM>, the upper face 13a of the heat radiating member <NUM> is made flat, so that a section in the form of a concentric sphere with a large volume is easily secured below each of the first light source <NUM> and the second light source <NUM> as compared with the case where a step is provided on the upper face 13a, without any partial breakage due to the step. Thus in the vehicular lamp <NUM>, a volume for heat transfer is secured in the heat radiating member <NUM> with respect to each of the first light source <NUM> and the second light source <NUM> so as to appropriately cool the first light source <NUM> and the second light source <NUM>. In addition, in the vehicular lamp <NUM>, the first light source <NUM> and the second light source <NUM> are attached to the upper face 13a in a flat shape, so that it is possible to provide both the light sources <NUM> and <NUM> on one and the same board <NUM> and reduce the cost of parts and the assembly cost.

In the vehicular lamp <NUM> of Example <NUM>, the changeover from the light distribution for passing (low beams) to the light distribution for traveling (high beams) and vice versa is allowed by providing the first light source <NUM>, the second light source <NUM>, the first reflector <NUM>, the second reflector <NUM>, the shade <NUM>, and the projection lens <NUM> in the positional relationship as described above. In a known vehicular lamp as the conventional vehicular lamp, a shade is so provided as to be displaceable from a position to block part of light forming a light distribution pattern to a position not to block the light and vice versa, and the changeover from the light distribution for passing to the light distribution for traveling and vice versa is allowed by displacing the shade with a driving part. The driving part for displacing the shade in such conventional vehicular lamp is a complicated, relatively expensive part, which causes the increase in number of parts and number of assembly processes, and the rise of the total cost. In contrast, in the vehicular lamp <NUM> of Example <NUM>, the first light source <NUM>, the second light source <NUM>, the first reflector <NUM>, the second reflector <NUM>, the shade <NUM>, and the projection lens <NUM> are only provided in the positional relationship as described above, so that the number of parts and the number of assembly processes are each reduced and the total cost is lowered as compared with the conventional vehicular lamp.

The vehicular lamp <NUM> of Example <NUM> has the following operational effects.

The vehicular lamp <NUM> includes the projection lens <NUM>, which projects the light emitted from the first light source <NUM>, so as to form the light distribution pattern LP for passing and projects the light emitted from the second light source <NUM>, so as to form the light distribution pattern HP for traveling. In the projection lens <NUM> of the vehicular lamp <NUM>, the lower lens part <NUM> having the lower focus Fd on the lens axis La and the upper lens part <NUM> having the upper focus Fu on the lens axis La, with the upper focus Fu being shorter in the focal length Df than the lower focus Fd, are set on the lower and upper sides of the lens axis La as a center, respectively. As a result, the vehicular lamp <NUM> is able to form the light distribution pattern LP for passing and the light distribution pattern HP for traveling so that the lower end portion of the light distribution pattern HP for traveling may overlap the upper end portion of the light distribution pattern LP for passing, and to be downsized with a simple configuration as compared with the prior art.

In the projection lens <NUM> of the vehicular lamp <NUM>, the gradual change lens parts <NUM>, each of which joins the lower lens part <NUM> and the upper lens part <NUM> and continuously changes the focal length Df from the lower focus Fd to the upper focus Fu, are set. As a result, the vehicular lamp <NUM> has the light exit face 17a of the projection lens <NUM>, which is produced as a single, smooth and stepless face, and appropriately forms the light distribution pattern LP for passing and the light distribution pattern HP for traveling, which partially overlap each other.

In the vehicular lamp <NUM>, the projection lens <NUM> is plane-symmetrically formed with respect to the vertical plane including the lens axis La and the gradual change lens parts <NUM> are so provided as to make a pair in the width direction. Thus, the projection lens <NUM> of the vehicular lamp <NUM> has a simple configuration, which makes the projection lens <NUM> easy to manufacture or assemble.

In the vehicular lamp <NUM>, the curvature of the light exit face 17a in the radial direction from the lens axis La is set to be larger in the upper lens part <NUM> than in the lower lens part <NUM>. Thus in the vehicular lamp <NUM>, the lower lens part <NUM> and the upper lens part <NUM> are set in the projection lens <NUM> by simply changing the curvature of the light exit face 17a, leading to a simple configuration. In the vehicular lamp <NUM>, the lower lens part <NUM> and the upper lens part <NUM> are set by setting the curvature of the light exit face 17a, so that it is possible to set the lower focus Fd and the upper focus Fu on the lens axis La while achieving a simple configuration. In addition, in the vehicular lamp <NUM>, the gradual change lens parts <NUM> are each set by setting the curvature of the light exit face 17a, so that it is possible to produce the light exit face 17a as a single, smooth and stepless face while achieving a simple configuration.

In the vehicular lamp <NUM>, the light emitted from the first light source <NUM> is caused to pass through the lower focus Fd from above the lens axis La and enter the lower lens part <NUM>, and the light emitted from the second light source <NUM> is caused to pass through the upper focus Fu from below the lens axis La and enter the upper lens part <NUM>. Thus, the vehicular lamp <NUM> allows, with a simple configuration, the light distribution pattern LP for passing to be formed with the light from the first light source <NUM>, and the light distribution pattern HP for traveling to be formed with the light from the second light source <NUM>, so that the two patterns may partially overlap each other.

The vehicular lamp <NUM> includes the first reflector <NUM>, which reflects the light emitted from the first light source <NUM> to the lower focus Fd, and the second reflector <NUM>, which reflects the light emitted from the second light source <NUM> to the upper focus Fu. In the vehicular lamp <NUM>, the first light source <NUM> and the second light source <NUM> are provided in one and the same plane below the lens axis La, and the second reflector <NUM> is provided below the lens axis La and ahead of the first light source <NUM> in the optical axis direction inside the first reflective face <NUM>. Consequently, in the vehicular lamp <NUM>, the light as emitted from the first light source <NUM> and reflected by the first reflector <NUM> and the light as emitted from the second light source <NUM> and reflected by the second reflector <NUM> are both allowed to enter the projection lens <NUM> even though the first light source <NUM> and the second light source <NUM> are provided in one and the same plane. In the vehicular lamp <NUM>, therefore, the mounting place (the upper face 13a of the heat radiating member <NUM> in Example <NUM>), where the first light source <NUM> and the second light source <NUM> are mounted, is made simple in shape and the first light source <NUM> and the second light source <NUM> are provided on one and the same board <NUM>, which results in a simple configuration.

Thus, the vehicular lamp <NUM> of Example <NUM> as the vehicular lamp according to an embodiment of the invention forms the light distribution pattern HP for traveling, which has the lower end portion overlapping the upper end portion of the light distribution pattern LP for passing, and is downsized with a simple configuration.

Next, a vehicular lamp 10A of Example <NUM> as an embodiment of the invention is described using <FIG>. The vehicular lamp 10A is obtained by changing the mode of setting of the first light source <NUM> and the second light source <NUM> in the vehicular lamp <NUM> of Example <NUM>. The vehicular lamp 10A is the same in basic idea and configuration as the vehicular lamp <NUM> of Example <NUM>, so that the same reference sign is imparted to a component or part having like configuration and detailed description on such component or part is omitted.

In the vehicular lamp 10A of Example <NUM>, the first light source <NUM> and the second light source <NUM> are provided on a heat radiating member 13A. The heat radiating member 13A includes a mount piece <NUM> and a heat radiating part <NUM>. The mount piece <NUM> is a place where the first light source <NUM> and the second light source <NUM> are mounted, and is in the form of a flat plate that is orthogonal to the vertical direction and includes the lens axis La. On an upper face 41a on the upper side in the vertical direction of the mount piece <NUM>, the first light source <NUM> is mounted through a board 18a, and the second light source <NUM> is mounted on a lower face 41b on the lower side in the vertical direction through a board 18b.

The heat radiating part <NUM> cools the first light source <NUM> and the second light source <NUM>. The heat radiating part <NUM> is formed continuously from an end portion on the back side in the optical axis direction of the mount piece <NUM>, extends in the vertical direction and the width direction with respect to the mount piece <NUM>, and is appropriately provided with a plurality of heat radiating fins. The heat radiating part <NUM> releases the heat outside, which is generated in the first light source <NUM> and the second light source <NUM> and transferred to the heat radiating part <NUM> through the mount piece <NUM>.

Accompanying the change in mode of setting of the first light source <NUM> and the second light source <NUM>, in the vehicular lamp 10A, a first reflector 14Ais so provided on the upper face 41a as to cover the first light source <NUM> and a second reflector 15A is so provided on the lower face 41b as to cover the second light source <NUM>. Thus, the mount piece <NUM> of the heat radiating member 13A serves as the parallel mounting part, which is provided on the lens axis La and along the lens axis La, on the upper side of which the first light source <NUM> and the first reflector 14A are provided, and on the lower side of which the second light source <NUM> and the second reflector 15A are provided. The first reflector 14A and the second reflector 15A are the same in configuration as the first reflector <NUM> and the second reflector <NUM> in Example <NUM> except that the positional relationship of setting is changed, and have the same positional relationship to the respective light sources (<NUM> and <NUM>) and the two focuses (the lower focus Fd and the upper focus Fu) as that in Example <NUM>.

In the vehicular lamp 10A, accompanying the fact that the mount piece <NUM> is provided on the lens axis La as described above, the shade <NUM> is provided at a front end of the mount piece <NUM>. As a result, in the vehicular lamp 10A, the shade <NUM> cooperates with the mount piece <NUM> to block light at the horizontal plane including the lens axis La on the back side in the optical axis direction of the lower focus Fd.

In the vehicular lamp 10A, the light from the first light source <NUM> as turned on is reflected by the first reflective face <NUM> of the first reflector 14A so as to cause the light to travel to the lower lens part <NUM> via the vicinity of the lower focus Fd of the lower lens part <NUM>. Thus in the vehicular lamp 10A, the light distribution pattern LP for passing is formed by guiding the light from the first light source <NUM> above the mount piece <NUM> to the lower focus Fd so as to cause the light to enter the lower lens part <NUM>.

In addition, in the vehicular lamp 10A, the light from the second light source <NUM> as turned on is reflected by the second reflective face <NUM> of the second reflector 15A so as to cause the light to travel to the upper lens part <NUM> via the vicinity of the upper focus Fu of the upper lens part <NUM>. Thus in the vehicular lamp 10A, the light distribution pattern HP for traveling is formed by guiding the light from the second light source <NUM> below the mount piece <NUM> to the upper focus Fu so as to cause the light to enter the upper lens part <NUM>.

The vehicular lamp 10A of Example <NUM> has the following operational effects. The vehicular lamp 10A is basically the same in configuration as the vehicular lamp <NUM> of Example <NUM> and, accordingly, has the same effects as Example <NUM>.

In addition, in the vehicular lamp 10A, an optical path for guiding the light from the first light source <NUM> to the lower focus Fd and an optical path for guiding the light from the second light source <NUM> to the upper focus Fu are vertically separated from each other by the mount piece <NUM>. Consequently, in the vehicular lamp 10A, the second reflector 15A is not arranged between the first light source <NUM> and the first reflector 14A on one hand and the lower focus Fd on the other, unlike the case of the vehicular lamp <NUM> of Example <NUM>, so that an optical path guiding from the first light source <NUM> to the lower focus Fd via the first reflector 14Ais improved in flexibility as compared with the vehicular lamp <NUM>.

Thus, the vehicular lamp 10A of Example <NUM> as the vehicular lamp according to an embodiment of the invention forms the light distribution pattern HP for traveling, which has the lower end portion overlapping the upper end portion of the light distribution pattern LP for passing, and is downsized with a simple configuration.

Next, a vehicular lamp 10B of Example <NUM> as an embodiment of the invention is described using <FIG>. The vehicular lamp 10B is obtained by changing the mode of setting of the first light source <NUM> and the second light source <NUM> in the vehicular lamp <NUM> of Example <NUM>. The vehicular lamp 10B is the same in basic idea and configuration as the vehicular lamp <NUM> of Example <NUM>, so that the same reference sign is imparted to a component or part having like configuration and detailed description on such component or part is omitted.

In the vehicular lamp 10B of Example <NUM>, the first light source <NUM> and the second light source <NUM> are mounted on a heat radiating member 13B. The heat radiating member 13B has an orthogonal mounting face 13b orthogonal to the optical axis direction, and is so formed as to appropriately include heat radiating fins or the like provided on the back side in the optical axis direction of the orthogonal mounting face 13b. The orthogonal mounting face 13b is a place where the first light source <NUM> and the second light source <NUM> are mounted, and extends in the vertical direction and the width direction around the lens axis La as a center. On the orthogonal mounting face 13b, a board 18B is so provided as to cross over the lens axis La in the vertical direction and the width direction. On the board 18B, the first light source <NUM> is implemented above the lens axis La and the second light source <NUM> is implemented below the lens axis La. The first light source <NUM> and the second light source <NUM> each have an optical axis of light emission (optical axis direction) substantially coincident with the optical axis direction. Thus, the heat radiating member 13B serves as the orthogonal mounting part, which extends orthogonally to the lens axis La, and on which the first light source <NUM> is provided above the lens axis La and the second light source <NUM> is provided below the lens axis La.

Accompanying the above, in the vehicular lamp 10B, a first reflector 14B includes a first reflecting part 14Ba and a second reflecting part 14Bb. The first reflecting part 14Ba is provided ahead of the first light source <NUM> in the optical axis direction and reflects the light emitted from the first light source <NUM> toward the second reflecting part 14Bb. The first reflecting part 14Ba in Example <NUM> is assumed as a paraboloid having a focus at the first light source <NUM>, as an example, and reflects the light emitted from the first light source <NUM> toward the second reflecting part 14Bb as a nearly parallel light.

The second reflecting part 14Bb is provided above the first reflecting part 14Ba in the vertical direction, and reflects the light reflected by the first reflecting part 14Ba so that the light may enter the lower lens part <NUM> via the lower focus Fd of the lower lens part <NUM> of the projection lens <NUM>. The second reflecting part 14Bb in Example <NUM> is assumed as a curved face making the first light source <NUM> and the vicinity of the lower focus Fd conjugate via the first reflecting part 14Ba, namely, a paraboloid having a focus in the vicinity of the lower focus Fd, as an example. Therefore, the second reflecting part 14Bb causes the light from the first light source <NUM> as reflected by the first reflecting part 14Ba to travel into the vicinity of the lower focus Fd.

In the vehicular lamp 10B, a second reflector 15B includes a first reflecting part 15Ba and a second reflecting part 15Bb. The first reflecting part 15Ba is provided ahead of the second light source <NUM> in the optical axis direction and reflects the light emitted from the second light source <NUM> toward the second reflecting part 15Bb. The first reflecting part 15Ba in Example <NUM> is assumed as a paraboloid having a focus at the second light source <NUM>, as an example, and reflects the light emitted from the second light source <NUM> toward the second reflecting part 15Bb as a nearly parallel light.

The second reflecting part 15Bb is provided below the first reflecting part 15Ba in the vertical direction, and reflects the light reflected by the first reflecting part 15Ba so that the light may enter the upper lens part <NUM> via the upper focus Fu of the upper lens part <NUM> of the projection lens <NUM>. The second reflecting part 15Bb in Example <NUM> is assumed as a curved face making the second light source <NUM> and the vicinity of the upper focus Fu conjugate via the first reflecting part 15Ba, namely, a paraboloid having a focus in the vicinity of the upper focus Fu, as an example. Therefore, the second reflecting part 15Bb causes the light from the second light source <NUM> as reflected by the first reflecting part 15Ba to travel into the vicinity of the upper focus Fu.

The first reflecting part 14Ba of the first reflector 14B and the first reflecting part 15Ba of the second reflector 15B are provided integrally with a shade 16B. The shade 16B extends backward in the optical axis direction to the vicinity of the orthogonal mounting face 13b, and the first reflecting part 14Ba and the first reflecting part 15Ba are provided in a back end portion of the shade 16B. The shade 16B is supported, at both ends in the width direction, by a frame member giving an external shape to the vehicular lamp 10B and extends in the optical axis direction on the lens axis La, and the front edge portion 16a is located in the vicinity of the lower focus Fd. The second reflecting part 14Bb of the first reflector 14B and the second reflecting part 15Bb of the second reflector 15B are each supported by the frame member at both ends in the width direction.

In the vehicular lamp 10B, the light from the first light source <NUM> as turned on is reflected by the first reflecting part 14Ba of the first reflector 14B so as to cause the light to travel to the second reflecting part 14Bb. The light is reflected by the second reflecting part 14Bb, then travels to the lower lens part <NUM> via the vicinity of the lower focus Fd of the lower lens part <NUM> and forms the light distribution pattern LP for passing. Thus in the vehicular lamp 10B, the light from the first light source <NUM> is guided above the shade 16B to the lower focus Fd so as to cause the light to enter the lower lens part <NUM>.

In addition, in the vehicular lamp 10B, the light from the second light source <NUM> as turned on is reflected by the first reflecting part 15Ba of the second reflector 15B so as to cause the light to travel to the second reflecting part 15Bb. The light is reflected by the second reflecting part 15Bb, then travels to the upper lens part <NUM> via the vicinity of the upper focus Fu of the upper lens part <NUM> and forms the light distribution pattern HP for traveling. Thus in the vehicular lamp 10B, the light from the second light source <NUM> is guided below the shade 16B to the upper focus Fu so as to cause the light to enter the upper lens part <NUM>.

The vehicular lamp 10B of Example <NUM> has the following operational effects. The vehicular lamp 10B is basically the same in configuration as the vehicular lamp <NUM> of Example <NUM> and, accordingly, has the same effects as Example <NUM>.

In addition, in the vehicular lamp 10B, an optical path for guiding the light from the first light source <NUM> to the lower focus Fd and an optical path for guiding the light from the second light source <NUM> to the upper focus Fu are vertically separated from each other by the shade 16B. Consequently, in the vehicular lamp 10B, the second reflector 15B is not arranged between the first reflector 14B and the lower focus Fd, unlike the case of the vehicular lamp <NUM> of Example <NUM>, so that an optical path guiding from the first light source <NUM> to the lower focus Fd is improved in flexibility as compared with the vehicular lamp <NUM>. In the vehicular lamp 10B, the first light source <NUM> and the second light source <NUM> are provided on the orthogonal mounting face 13b of the heat radiating member 13B through the single board 18B, unlike the case of the vehicular lamp 10A of Example <NUM>, so that assembly processes are made simple on the whole as compared with the vehicular lamp 10A.

Thus, the vehicular lamp 10B of Example <NUM> as the vehicular lamp forms the light distribution pattern HP for traveling, which has the lower end portion overlapping the upper end portion of the light distribution pattern LP for passing, and is downsized with a simple configuration.

In Example <NUM>, the first reflector 14B includes the first reflecting part 14Ba and the second reflecting part 14Bb, and the second reflector 15B includes the first reflecting part 15Ba and the second reflecting part 15Bb. The first and second reflectors 14B and 15B, however, are not limited to the configuration in Example <NUM>, and it is also possible to provide the first reflector 14B, to which a third reflecting part 14Bc is added, and the second reflector 15B, to which a third reflecting part 15Bc is added, as illustrated in <FIG> with a long-dashed double-dotted line.

The third reflecting part 14Bc reflects the light, which is emitted from the first light source <NUM> and travels toward the front side of the second reflecting part 14Bb without reaching the first reflecting part 14Ba, toward the lower lens part <NUM> and is provided ahead of the second reflecting part 14Bb. The third reflecting part 14Bc may be assumed as a free-form surface based on an ellipse having a first focus at the first light source <NUM> and a second focus in the vicinity of the lower focus Fd or may be of any other configuration. In the example illustrated in <FIG>, the third reflecting part 14Bc is assumed as a free-form surface based on an ellipse and reflects the light from the first light source <NUM> so as to cause the light to travel to the lower lens part <NUM> without passing through the lower focus Fd, with at least part of the light distribution pattern LP for passing being formed with such light. The third reflecting part 14Bc is not limited to the configuration in Example <NUM> but may reflect the light from the first light source <NUM> so as to cause the light to pass through the lower focus Fd.

The third reflecting part 15Bc reflects the light, which is emitted from the second light source <NUM> and travels toward the front side of the second reflecting part 15Bb without reaching the first reflecting part 15Ba, toward the upper lens part <NUM> and is provided ahead of the second reflecting part 15Bb. The third reflecting part 15Bc may be assumed as a free-form surface based on an ellipse having a first focus at the second light source <NUM> and a second focus in the vicinity of the upper focus Fu or may be of any other configuration. In the example illustrated in <FIG>, the third reflecting part 15Bc is of the configuration as above and reflects the light from the second light source <NUM> so as to cause the light to pass through the upper focus Fu and then travel to the upper lens part <NUM>, with at least part of the light distribution pattern HP for traveling being formed with such light. The third reflecting part 15Bc is not limited to the configuration in Example <NUM> but may reflect the light from the second light source <NUM> so as to cause the light not to pass through the upper focus Fu. If the third reflecting part 14Bc and the third reflecting part 15Bc are provided as described above, the light from the first light source <NUM> and the light from the second light source <NUM> are used more effectively to form the light distribution pattern LP for passing and the light distribution pattern HP for traveling.

In Example <NUM>, the first reflecting part 14Ba and the second reflecting part 14Bb of the first reflector 14B and the first reflecting part 15Ba and the second reflecting part 15Bb of the second reflector 15B are each assumed as a free-form surface. The first and second reflectors 14B and 15B, however, are not limited to the configuration in Example <NUM> as long as the first reflector 14B causes the light from the first light source <NUM> to travel to the lower lens part <NUM> and form the light distribution pattern LP for passing and the second reflector 15B causes the light from the second light source <NUM> to travel to the upper lens part <NUM> and form the light distribution pattern HP for traveling. In <FIG>, a vehicular lamp 10C including exemplary reflectors is illustrated. In the vehicular lamp 10C, a first reflecting part 14Ca of a first reflector 14C and a first reflecting part 15Ca of a second reflector 15C are each assumed as a flat face and, accompanying that, the second reflecting part 14Bb and the second reflecting part 15Bb are changed in degree of curviness (focal position). The vehicular lamp 10C is the same in configuration as the vehicular lamp 10B of Example <NUM> except for the above and, accordingly, has the same effects as the vehicular lamp 10B. In the vehicular lamp 10C, similarly to the case illustrated in <FIG> with a long-dashed double-dotted line, a third reflecting part 14Cc and a third reflecting part 15Cc may be provided and, in that case, the light from the first light source <NUM> and the light from the second light source <NUM> are used more effectively to form the light distribution pattern LP for passing and the light distribution pattern HP for traveling.

The vehicular lamp according to embodiments of the invention has been described above based on the respective examples, to which a specific configuration is not limited, and any design modification, addition, and the like are allowable as long as they do not depart from the gist of the invention according to the Claims.

The configurations of the respective examples are as described above. The configurations of the respective examples, however, are not limitative, and another configuration may be employed as long as the projection lens <NUM> forms the light distribution pattern LP for passing with the light from the first light source <NUM> and the light distribution pattern HP for traveling with the light from the second light source <NUM>, and includes the lower lens part <NUM> having the lower focus Fd set on the lens axis La and the upper lens part <NUM> having the upper focus Fu set on the lens axis La, with the upper focus Fu being shorter in the focal length Df than the lower focus Fd. In other words, the positional relationship among the first light source <NUM>, the second light source <NUM>, the first reflector <NUM>, and the second reflector <NUM> is not limited to the positional relationships in the respective examples but may be set as appropriate.

In the respective examples, the lower lens part <NUM>, the upper lens part <NUM>, and the gradual change lens parts <NUM> are set in the projection lens <NUM>. The configurations of the respective examples, however, are not limitative, and the gradual change lens parts <NUM> may not be set as long as the lower lens part <NUM> and the upper lens part <NUM> are set.

Claim 1:
A vehicular lamp (<NUM>, 10A, 10B, 10C) comprising a projection lens (<NUM>) projecting light emitted from a first light source (<NUM>) to form a light distribution pattern (LP) for passing, and projecting light emitted from a second light source (<NUM>) to form a light distribution pattern (HP) for traveling,
wherein a lower lens part (<NUM>) and an upper lens part (<NUM>) are set in the projection lens (<NUM>) about a lens axis as a center,
wherein a lower focus (Fd) is set on the lens axis (La) in the lower lens part (<NUM>), and
wherein an upper focus (Fu) shorter in focal length than the lower focus (Fd) is set on the lens axis (La) in the upper lens part (<NUM>)
characterized in that
a gradual change lens part (<NUM>) joining the lower lens part (<NUM>) and the upper lens part (<NUM>) is set in the projection lens (<NUM>), and
the gradual change lens part (<NUM>) continuously changes a focal length from the lower focus to the upper focus.