Patent Description:
There is known a configuration in which respective functions corresponding to a reflector, a shade, a projection lens, and the like are integrated into one vehicular light-guiding body (see, for example, <CIT>). That is, such a vehicular light-guiding body includes an incidence surface on which light from a light source is incident, an internal reflection surface (corresponding to a reflector) that internally reflects the incident light, a light blocking part (corresponding to a shade) that blocks a portion of the internally reflected light, and an emission surface (corresponding to a projection lens) that emits the light internally reflected to pass through the light blocking part, and projects a diffusion pattern PF toward a front of a vehicle.

<CIT> relates to an optical module for a motor vehicle including at least one light source capable of emitting an initial light beam and a primary optical means capable of receiving the initial light beam and having a cutoff member arranged to transform the initial light beam into a secondary light beam oriented in a longitudinal direction and exhibiting a predetermined bottom cutoff extending overall transversely. A projection means is arranged to project a final light beam exhibiting a top cutoff formed by an inverted image of the secondary light beam with cutoff, wherein the primary optical means has a light deflection member arranged to deflect a part of the light rays of the initial light beam below the cutoff of the secondary beam toward the projection means.

In the vehicular light-guiding body described in <CIT>, there is a need to improve the efficiency of light utilization such that light incident from the incidence surface can be reflected internally to reach the emission surface with as little loss as possible.

In view of the above, we have appreciated that it would be desirable to provide a vehicular light-guiding body and a vehicular lamp unit capable of improving light utilization efficiency.

A vehicular light-guiding body according to the present invention includes: an incidence surface on which light from a light source is incident; a first reflection surface that internally reflects the light incident from the incidence surface and converts the light into substantially parallel light; a second reflection surface that internally reflects, forward in a front-rear direction, when the vehicular light guiding body is mounted on a vehicle, the substantially parallel light from the first reflection surface; a light blocking part that blocks a portion of the light reflected by the second reflection surface; a connecting surface that connects the second reflection surface and the light blocking part, and has a transmission surface which transmits a portion of the light reflected by the second reflection surface from a lower side in an up-down direction, when the vehicular light guiding body is mounted on a vehicle, to a guiding body outer part, and directs the light forward in the front-rear direction; a re-incidence surface that is disposed on a front side in the front-rear direction with respect to the transmission surface and on a lower side in the up-down direction with respect to the light blocking part, and allows the light transmitted from the transmission surface to the guiding body outer part to be re-incident; and an emission surface that emits the light internally reflected by the second reflection surface, and the light incident from the re-incidence surface; wherein the transmission surface includes transmission surfaces which are disposed on both sides of the vehicular light-guiding body with a space at a central part in a left-right direction when the vehicular light guiding body is mounted on a vehicle.

In the above vehicular light-guiding body, the second reflection surface may have a condensing pattern forming surface that internally reflects the substantially parallel light such that the substantially parallel light is condensed forward in the front-rear direction, and the transmission surface may be disposed within a region where reflected light internally reflected by the condensing pattern forming surface passes, as viewed from the up-down direction.

In the above vehicular light-guiding body, the connecting surface may have a recessed part disposed on the front side in the front-rear direction with respect to the transmission surface, and recessed toward a guiding body inner part, and an inclined surface that is a portion of the recessed part, that is provided between the transmission surface and the light blocking part in the connecting surface so as to be inclined downward in the up-down direction toward the front side in the front-rear direction, and that internally reflects, forward in the front-rear direction, a portion of the light reflected by the second reflection surface may be further provided.

In the above vehicular light-guiding body, the inclined surface may have a first external light blocking part that is disposed so as to protrude on the guiding body outer part, and blocks a portion of light transmitted from the transmission surface to the guiding body outer part.

In the above vehicular light-guiding body, a second external light blocking part that is disposed on the front side in the front-rear direction with respect to the transmission surface in the connecting surface so as to protrude on the guiding body outer part, and blocks a portion of light transmitted from the transmission surface to the guiding body outer part may be further provided.

In the above vehicular light-guiding body, the emission surface may project a diffusion pattern toward a front of a vehicle.

A vehicular lamp unit according to the present invention includes: a light source; and a plurality of the above vehicular light-guiding bodies, each of the vehicular light-guiding bodies being configured to guide and emit light from the light source.

According to the present invention, it is possible to improve light utilization efficiency.

Hereinafter, an embodiment of a vehicular light-guiding body and a vehicular lamp unit according to the present invention will be described with reference to the drawings. This invention is not limited to the embodiment. In addition, components in the following embodiment include those that are substitutable and easy to be replaced by those skilled in the art, or those that are substantially identical. In the following description, the front-rear, up-down, and right-left directions indicate directions in an on-board state in which a vehicular headlight is mounted on a vehicle, and also indicate the directions when viewed in the direction of travel of the vehicle from a driver's seat. In this embodiment, the up-down direction is parallel to the vertical direction and the left-right direction is the horizontal direction.

<FIG> is a plan view illustrating an example of a vehicular lamp <NUM> according to this embodiment. <FIG> is a bottom view illustrating an example of the vehicular lamp <NUM> according to this embodiment. <FIG> is a diagram illustrating a configuration taken along the A-A section in <FIG>.

The vehicular lamp <NUM> can project a diffusion pattern PF (see <FIG>) described below toward a front of a vehicle. In this embodiment, the diffusion pattern PF includes, for example, a low-beam pattern P1 and an overhead pattern P2. The vehicular lamp <NUM> includes light sources <NUM>, and a vehicular light-guiding body <NUM>. The vehicular lamp <NUM> may further include another unit having a light source, a reflector, a shade, a projection lens, and the like. In this embodiment, the following description will take as an example a configuration of the vehicular lamp <NUM> mounted on a vehicle that travels on a left-hand traffic.

For each light source <NUM>, in this embodiment, a semiconductor type light source such as an LED and an OLED (organic EL), a laser light source and the like are used, for example. Light emitting surfaces <NUM> are disposed so as to face incidence surfaces <NUM> of the vehicular light-guiding body <NUM> described later. The light emitting surfaces <NUM> are disposed in a state of being directed toward the vehicular light-guiding body <NUM>. In this embodiment, a plurality of the light sources <NUM>, for example, four are disposed in the left-right direction. The number of the light sources <NUM> is not limited to four, but may be three or less, or five or more.

The vehicular light-guiding body <NUM> guides light from the light sources <NUM> and emits the light toward the front of the vehicle in an onboard state. The vehicular light-guiding body <NUM> according to this embodiment has a configuration in which respective functions corresponding to a reflector, a shade, a projection lens and the like in a conventional projector-type vehicular headlight, for example, are integrated. As illustrated in <FIG>, the vehicular light-guiding body <NUM> includes the incidence surfaces <NUM>, first reflection surfaces <NUM>, second reflection surfaces <NUM>, a light blocking part <NUM>, a connecting surface <NUM>, a re-incidence surface <NUM>, and an emission surface <NUM>.

A plurality of the incidence surfaces <NUM> are provided, for example, one for each light source <NUM>. Each incidence surface <NUM> may be provided at such a position as not to correspond to the light source <NUM> in a one-to-one manner. For example, a plurality of the incidence surfaces <NUM> may be provided for the single light source <NUM>. The plurality of incidence surfaces <NUM> are disposed side by side in the left-right direction in the onboard state. The incidence surfaces <NUM> are each formed in the shape of a cone, for example. In this embodiment, for example, the four incidence surfaces <NUM> are arranged. The diameter of each of the incidence surfaces <NUM> disposed on the outer side in the left-right direction is smaller than the diameter of each of the incidence surfaces <NUM> disposed on the central side in the left-right direction. In this embodiment, the diameter of each of the two incidence surfaces <NUM> disposed on the outer side in the left-right direction is smaller than the diameter of each of the two incidence surfaces <NUM> on the central side in the left-right direction. Hereinafter, the two incidence surfaces <NUM> on the central side in the left-right direction are each written as a central incidence surface <NUM>, the two incidence surfaces on the outer side in the left-right direction are each written as an outer incidence surface 21N, and both may be distinguished from each other.

Each incidence surface <NUM> has a first surface 21a and a second surface 21b, as illustrated in <FIG>. Light from each light source <NUM> is incident on the first surface 21a and the second surface 21b. The first surface 21a faces the light emitting surface <NUM>. The first surface 21a is a flat surface or a convex surface protruding toward the light source <NUM>. The second surface 21b is disposed on the lateral side of the light source <NUM> and is disposed in the shape of a cylindrical surface so as to surround the light emitting surface <NUM> and the first surface 21a of the light source <NUM>.

Each first reflection surface <NUM> internally reflects light incident from the incidence surface <NUM> and converts the reflected light into substantially parallel light. The first reflection surface <NUM> is disposed so as to surround the second surface 21b of the incidence surface <NUM>, and reflects light incident from the second surface 21b toward the second reflection surface <NUM>. In this embodiment, the first reflection surfaces <NUM> are provided so as to correspond to the incidence surfaces <NUM>. The two first reflection surfaces <NUM> disposed on the central side in the left-right direction are disposed in a state of being partially overlapped on each other.

Each second reflection surface <NUM> has a shape based on a paraboloid of revolution. The second reflection surfaces <NUM> has a focal point P that coincides with or substantially coincides with a focal point of the paraboloid of revolution. The focal point P is disposed at a position in the vicinity of the focal point of the emission surface <NUM>, which will be described below. The second reflection surface <NUM> reflects substantially parallel light from the first reflection surface <NUM> toward the focal point P, that is, toward the front of the vehicle. The second reflection surface <NUM> has an axis parallel to an optical axis of the substantially parallel light reflected by the first reflection surface <NUM>, and internally reflects the substantially parallel light toward the focal point P of the paraboloid of revolution.

A plurality of the second reflection surfaces <NUM> are disposed side by side in the left-right direction in the onboard state, as illustrated in <FIG>. The plurality of second reflection surfaces <NUM> include a condensing pattern forming surface <NUM> and diffusion pattern forming surfaces 23N. The condensing pattern forming surface <NUM> internally reflects the substantially parallel light such that the substantially parallel light passes through the focal point P and the vicinity of the focal point P. The condensing pattern forming surface <NUM> is disposed at the center in the left-right direction. The condensing pattern forming surface <NUM> is disposed so as to correspond to the two central incidence surfaces <NUM>. The condensing pattern forming surface <NUM> reflects substantially parallel light that is incident on each of the two central incidence surfaces <NUM>, and is reflected by each of the first reflection surfaces <NUM>. In a case where the vehicular light-guiding body <NUM> is viewed from the lower side, as illustrated in <FIG>, the condensing pattern forming surface <NUM> can reflect the substantially parallel light to a region between a virtual straight line LMa and a virtual straight line LMb in the left-right direction, for example.

Each diffusion pattern forming surface 23N internally reflects substantially parallel light such that the substantially parallel light passes through a position shifted to the outer side in the horizontal direction in the onboard state with respect to the focal point P including the focal point P. Therefore, the diffusion pattern forming surfaces 23N each have a shape in which, for example, an edge of the condensing pattern forming surface <NUM> side in the left-right direction is deformed to the focal point P side (forward) with respect to the shape based on the paraboloid of revolution. Among the plurality of second reflection surfaces <NUM>, the second reflection surfaces <NUM> disposed on the outer side in the left-right direction with respect to the condensing pattern forming surface <NUM> is the diffusion pattern forming surfaces 23N. The diffusion pattern forming surfaces 23N are disposed so as to correspond to the respective outer incidence surfaces 21N. The diffusion pattern forming surfaces 23N each reflect the substantially parallel light incident on the outer incidence surface 21N and reflected by the first reflection surface <NUM>. In a case where the vehicular light-guiding body <NUM> is viewed from the lower side, as illustrated in <FIG>, the diffusion pattern forming surface 23N reflects the substantially parallel light to each of an region between a virtual straight line LNa and a virtual straight line LNb in the left-right direction and an region between a virtual straight line LNc and a virtual straight line LNd in the left-right direction, for example.

In a case of being viewed from the lower side as illustrated in <FIG>, reflected light internally reflected by the condensing pattern forming surface <NUM> mainly passes through the region between the virtual straight line LMa and the virtual straight line LMb in the left-right direction. In addition, reflected light internally reflected on the diffusion pattern forming surface 23N mainly passes through each of the region between the virtual straight line LNa and the virtual straight line LNb and the region between the virtual straight line LNc and the virtual straight line LNd, and partial light passes through the region (rear side in the front-rear direction) between the virtual straight line LNb and the virtual straight line LNc. In this embodiment, a portion of region, through which the reflected light internally reflected on the condensing pattern forming surface <NUM> mainly pass, and a portion of the reflected light internally reflected on each of the diffusion pattern forming surfaces 23N passes, is set as an region AR. The region AR has a tapered shape from the second reflection surface <NUM> side to the front side. In addition, the region AR has a shape along the virtual straight line LNb and the virtual straight line LNc indicating a range where the reflected light internally reflected on each of the diffusion pattern forming surfaces 23N mainly passes.

The light blocking part <NUM> blocks a portion of light internally reflected by the second reflection surfaces <NUM>. <FIG> is a perspective view illustrating an example of the vehicular light-guiding body <NUM> viewed from a lower side. <FIG> is an enlarged view illustrating a portion of <FIG>.

As illustrated in <FIG>, for example, the light blocking part <NUM> is provided in a corner <NUM> formed by the connecting surface <NUM> and the re-incidence surface <NUM> described below. The corner <NUM> has a recessed shape when the vehicular light-guiding body <NUM> is viewed from the outer side (lower side). The corner <NUM> linearly extends in the left-right direction. The light blocking part <NUM> forms a cutoff line CL (see <FIG>) of the low-beam pattern P1 in the diffusion pattern PF described later, at the corner <NUM>. The cutoff line CL includes a horizontal cutoff line and an oblique cutoff line. The corner <NUM> has a horizontal portion (not illustrated) for forming the horizontal cutoff line and an inclined portion (not illustrated) for forming the oblique cutoff line.

The light blocking part <NUM> is provided in a region including the corner <NUM>. The light blocking part <NUM> may block light, for example, by refracting or internally reflecting, in a direction different from the direction of the emission surface <NUM>, light which arrives at the light blocking part <NUM>, or may block light by disposing a light absorbing layer on a portion, which corresponds to the light blocking part <NUM>, in the connecting surface <NUM> including the corner <NUM>, and absorbing light by the light absorbing layer. The light internally reflected or refracted by the light blocking part <NUM> is emitted to the outside of the vehicular light-guiding body <NUM> and absorbed by an inner housing or the like disposed outside the vehicular light-guiding body <NUM>.

The connecting surface <NUM> connects the second reflection surfaces <NUM> and the light blocking part <NUM>. The connecting surface <NUM> is located on the lower side of the vehicular light-guiding body <NUM>, and is disposed along a horizontal plane. The connecting surface <NUM> is provided with a protruding part <NUM>.

The protruding part <NUM> is disposed in front of the condensing pattern forming surface <NUM>. The protruding part <NUM> has a configuration of protruding in a V-shape from the connecting surface <NUM> toward the lower side in the cross-sectional view. The protruding part <NUM> has transmission surfaces <NUM> disposed on the front side in the front-rear direction, and transmission-side reflection surfaces <NUM> disposed on the rear side. As illustrated in <FIG>, the protruding part <NUM> has a tapered shape toward the front side. With the above, the transmission surfaces <NUM> and the transmission-side reflection surfaces <NUM> each has a tapered shape toward the front side.

The transmission surfaces <NUM> has, for example, a planar shape, and has an inclined shape from the rear side toward the front side. Each transmission surface <NUM> transmits light from the second reflection surface <NUM> to an outer part of the vehicular light-guiding body <NUM>, and refracts the light forward (see <FIG>). The light transmitted from each transmission surface <NUM> to the guiding body outer part to travel forward is incident on the re-incidence surface <NUM> described below, and forms the overhead pattern P2 (see <FIG>) described below emitted from the emission surface <NUM> toward the front of the vehicle.

As illustrated in <FIG>, the transmission surfaces <NUM> are disposed within a region where reflected light internally reflected on the condensing pattern forming surface <NUM> passes, as viewed from the lower side in the up-down direction, for example. In this embodiment, as viewed from the lower side, the transmission surfaces <NUM> are disposed within the region AR that is tapered forward from both ends in the left-right direction of the condensing pattern forming surface <NUM> to the focal point P.

The transmission-side reflection surfaces <NUM> each have a shape inclined upward from the front side to the rear side. Each transmission-side reflection surface <NUM> reflects, toward the transmission surface <NUM> on the front side, light which enters a protruding portion from the rear side or the upper side.

The protruding part <NUM> has a planar cutout surface 29a at the center in the left-right direction. The cutout surface 29a is provided such that a central part in the left-right direction of the protruding part <NUM> is cut out along the horizontal plane. The cutout surface 29a is provided in the protruding part <NUM>, and therefore the above transmission surfaces <NUM> and transmission-side reflection surfaces <NUM> are disposed on the both sides with a space at the central part in the left-right direction. Inside the vehicular light-guiding body <NUM>, light incident on the cutout surface 29a is internally reflected on the cutout surface 29a. The cutout surface 29a is provided, so that it is possible to control the luminous intensity of the overhead pattern P2 (see <FIG>). In this embodiment, with the cutout surface 29a, the transmission surfaces <NUM> are disposed on the left and right at an interval, and therefore it is possible to obtain sufficiently diffusion to the left and right of the overhead pattern P2, and it is possible to suppress excessive rise of the luminous intensity of the central part. The cutout surface 29a may not be provided. In addition to the configuration in which the central part of a transmission surface <NUM> may has the cutout surface 29a, for example, the areas of the transmission surface <NUM> may be reduced, or a portion of the transmission surface <NUM> may be processed.

The connecting surface <NUM> is provided with a recessed part <NUM>. The recessed part <NUM> is disposed between the transmission surfaces <NUM> and the light blocking part <NUM> in the front-rear direction. The recessed part <NUM> has a shape recessed in a V-shape from the connecting surface <NUM> toward the inner side of the vehicular light-guiding body <NUM> in the cross-sectional view. The recessed part <NUM> has an inclined surface <NUM> and an upper reflection surface <NUM>. That is, the inclined surface <NUM> is a portion of the recessed part <NUM>.

The inclined surface <NUM> has, for example, a planar shape, and is inclined downward in the up-down direction from the rear side to the front side in the front-rear direction. The inclined surface <NUM> internally reflects, toward the front side, a portion of light reflected on each second reflection surface <NUM>. The light internally reflected on the inclined surface <NUM> passes through a position closer to the light blocking part <NUM>, compared to light internally reflected on the connecting surface <NUM> that is not provided with the inclined surface <NUM>. Accordingly, in a case where the light emits from the emission surface <NUM>, the light is projected to a region closer to the cutoff line CL. Therefore, compared to the case where no inclined surface <NUM> is provided, visibility from a long distance is improved. The inclined surface <NUM> disposed in front of the transmission surfaces <NUM> is provided as a portion of the recessed part <NUM>, so that it is possible to prevent blocking of light transmitted through the transmission surfaces <NUM> and traveling toward the guiding body outer part disposed on the front side, for example, compared to the case where the inclined surface <NUM> is provided as a portion of the protruding part that protrudes toward the lower side of the connecting surface <NUM>. As illustrated in <FIG>, the recessed part <NUM> has a tapered shape toward the front side. With the above, for example, the inclined surface <NUM> also has a tapered shape toward the front side.

The inclined surface <NUM> is provided with a first external light blocking part <NUM>. The first external light blocking part <NUM> is configured such that a portion of the inclined surface <NUM> protrudes downward. The first external light blocking part <NUM> blocks a portion of light transmitted from each transmission surface <NUM> to the guiding body outer part to travel forward. Specifically, the first external light blocking part <NUM> blocks light projected to a portion of a region PA at a lower side on an opposite lane side in the overhead pattern P2 (see <FIG>).

The upper reflection surface <NUM> has, for example, a planar shape, and is inclined downward in the up-down direction from the front side to the rear side in the front-rear direction, contrary to the inclined surface <NUM>. The upper reflection surface <NUM> is disposed behind the inclined surface <NUM>, and forms the V-shaped recessed part <NUM> to together with the inclined surface <NUM>. The upper reflection surface <NUM> has a larger inclination angle to the connecting surface <NUM> than the inclined surface <NUM>. The upper reflection surface <NUM> internally reflects a portion of light reflected on the second reflection surfaces <NUM> toward an upper surface <NUM>. The light reflected on the upper reflection surface <NUM> is partially emitted from the upper surface <NUM> to the outside of the vehicular light-guiding body <NUM>, and partially reflected on the upper surface <NUM> to be diffused. The light reflected on the upper reflection surface <NUM> does not reach the emission surface <NUM>, and is absorbed by an inner housing or the like disposed outside the vehicular light-guiding body <NUM>. Therefore, generation of glare light is suppressed.

The connecting surface <NUM> is provided with a second external light blocking part <NUM>. The second external light blocking part <NUM> is disposed between the transmission surfaces <NUM> and the recessed part <NUM>. The second external light blocking part <NUM> is configured such that a portion of the connecting surface <NUM> protrudes downward. The second external light blocking part <NUM> is disposed with in the region AR through which substantially parallel light internally reflected on the condensing pattern forming surface <NUM> passes, as viewed from the up-down direction. The second external light blocking part <NUM> blocks a portion of light transmitted from the transmission surfaces <NUM> to the guiding body outer part to travel forward. Specifically, the second external light blocking part <NUM> blocks light projected to a region PB in the vicinity of the H-H line in the overhead pattern P2 (see <FIG>).

The above first external light blocking part <NUM> and second external light blocking part <NUM> may block light by, for example, refracting or internally reflecting, in the direction opposite to the direction of the re-incidence surface <NUM>, light which reaches the first external light blocking part <NUM> and the second external light blocking part <NUM>, or light absorbing layers may be disposed on surfaces of the first external light blocking part <NUM> and the second external light blocking part <NUM> may block by absorbing light by the light absorbing layers. The light internally reflected or refracted by each of the first external light blocking part <NUM> and the second external light blocking part <NUM> is absorbed by the inner housing or the like disposed outside the vehicular light-guiding body <NUM>.

The re-incidence surface <NUM> is provided so as to be bent downward with respect to the connecting surface <NUM>. The re-incidence surface <NUM> is formed so as to be inclined forward from an upper part to a lower part. The re-incidence surface <NUM> causes light transmitted from each of the transmission surfaces <NUM> to the outside to be re-incident. The light re-incident from the re-incidence surface <NUM> travels from the lower side of the light blocking part <NUM> toward the emission surface <NUM>.

The emission surface <NUM> emits the light internally reflected by each second reflection surface <NUM> to not to be blocked by the light blocking part <NUM>, and the light incident from the re-incidence surface <NUM>, and projects the diffusion pattern PF (see <FIG>) toward the front of the vehicle. In this embodiment, the emission surface <NUM> has, for example, a curved surface, and has a focal point (not illustrated), and an optical axis. The emission surface <NUM> may be, for example, a planar shape, and other optical element that projects light emitted from the emission surface <NUM> toward the front of the vehicle may be disposed. The focal point of the emission surface <NUM> is disposed at a position in the vicinity of the focal point P of the second reflection surfaces <NUM>. In this embodiment, the width in the left-right direction of the emission surface <NUM> is narrower than the width in the left-right direction of the second reflection surfaces <NUM>. In this case, the dimensions of the emission surface <NUM> when viewed from the outside can be controlled.

Alight diffusion part such as a prism part may be formed on the upper surface <NUM> of the vehicular light-guiding body <NUM>. The light diffusion part diffuses the light internally reflected by the second reflection surfaces <NUM>, and the light internally reflected by the upper reflection surface <NUM>. Therefore, the light emitted from the upper surface <NUM> to the outside of the vehicular light-guiding body <NUM> can be inhibited from becoming glare.

Now, operation of the vehicular lamp <NUM> configured as described above will be described. <FIG> is a diagram illustrating an example of the diffusion pattern projected on a virtual screen in front of a vehicle. <FIG> illustrates the pattern for a vehicle which drives on the left side of the road. In <FIG>, the V-V line indicates a vertical line of the screen, and the H-H line indicates a horizontal line on the left and right of the screen. Herein, an intersection of the vertical line and the horizontal line is assumed to be a reference position in the horizontal direction.

Each of the light sources <NUM> in the vehicular lamp <NUM> is turned on, so that light emitted from each of the light emitting surfaces <NUM> is emitted. This light is incident on the vehicular light-guiding body <NUM> from the first surface 21a and the second surface 21b of each incidence surface <NUM>. The light incident from each first surface 21a travels toward the first reflection surface <NUM>. The light incident from each second surface 21b is internally reflected toward the second reflection surface <NUM> in the first reflection surface <NUM>.

As illustrated in <FIG>, light L1, light L2, light L3, light L4 and light L5 which are each a portion of light reflected by the condensing pattern forming surface <NUM> in the second reflection surfaces <NUM> is guided by the vehicular light-guiding body <NUM>, for example, as described below.

For example, the light L1 enters the protruding part <NUM>, is transmitted through the transmission surfaces <NUM> disposed on the front side of the protruding part <NUM>, and emits to the guiding body outer part. This light L1 travels to the guiding body outer part located on the front side, passes below the light blocking part <NUM>, and is re-incident on an inner part of the vehicular light-guiding body <NUM> from the re-incidence surface <NUM>. The re-incident light L1 reaches the emission surface <NUM>, and emits from the emission surface <NUM> toward the front of the vehicle.

The light L2 enters the protruding part <NUM>, is transmitted through the transmission surfaces <NUM> disposed on the front side of the protruding part <NUM>, and emitted to the guiding body outer part. This light L1 travels to the guiding body outer part located on the front side, but is blocked or reflected by the second external light blocking part <NUM>. This light L2 absorbs by the inner housing or the like disposed outside the vehicular light-guiding body <NUM>.

The light L3 crosses over the protruding part <NUM> and reaches the inclined surface <NUM> of the recessed part <NUM>. The light L3 is internally reflected toward the front of the vehicle by the inclined surface <NUM>, passes above the light blocking part <NUM>, and reaches the emission surface <NUM>. The light L3 that reaches the emission surface <NUM> is emitted from the emission surface <NUM> to the front of the vehicle.

The light L4 crosses over the protruding part <NUM>, and reaches the upper reflection surface <NUM> of the recessed part <NUM>. The light L4 is internally reflected toward the front of the vehicle by the upper reflection surface <NUM>. The light L4 is emitted to the guiding body outer part, for example, in a state of being reflected by the upper surface <NUM> of the vehicular light-guiding body <NUM>, and being diffused by the prism part provided in the upper surface <NUM>. This light L4 is absorbed by the inner housing or the like disposed outside the vehicular light-guiding body <NUM>.

The light L5 crosses over the protruding part <NUM> and the recessed part <NUM>, and reaches the light blocking part <NUM>. The light L5 is partially blocked by the light blocking part <NUM>, and partially passes the light blocking part <NUM>. The light L5 that passes the light blocking part <NUM> reaches the emission surface <NUM>. The light L5 that reaches the emission surface <NUM> is emitted from the emission surface <NUM> to the front of the vehicle.

The light L1, the light L3, and the light L5 emitted from the emission surface <NUM> are projected as the diffusion pattern PF toward the front of the vehicle, as illustrated in <FIG>. Specifically, the light L1, the light L3, and the light L5 that pass above the light blocking part <NUM>, and reach the emission surface <NUM> form a condensing pattern P1a including the cutoff line CL in the low-beam pattern P1. In <FIG>, a state in which the oblique cutoff line CLa in the cutoff line CL is formed so as to be inclined downward toward the right side is described as an example, but the present invention is not limited to this. Similar description can be made also for a case where the oblique cutoff line is inclined downward toward the left side.

The light L3 internally reflected by the inclined surface <NUM> passes a position closer to the light blocking part <NUM> compared to light internally reflected by a connecting surface <NUM> that is not provided with the inclined surface <NUM>. Accordingly, in a case where the light emits from the emission surface <NUM>, the light is projected to a region closer to the cutoff line CL. Therefore, compared to the case where no inclined surface <NUM> is provided, visibility from a long distance is improved.

Although diffusion light reflected by each diffusion pattern forming surfaces 23N in the second reflection surfaces <NUM> is not illustrated, the diffusion light partially crosses over the connecting surface <NUM>, and is partially reflected by the connecting surface <NUM>, passes above light blocking part <NUM>, and reaches the emission surface <NUM>. The diffusion light emitted from the emission surface <NUM> forms a diffusion pattern P1b in the low-beam pattern P1.

The light L1 that is emitted to the guiding body outer part by the transmission surfaces <NUM>, passes below the light blocking part <NUM>, and reaches the emission surface <NUM> forms the overhead pattern P2. It is possible to improve the utilization efficiency of light by using, as the overhead pattern P2, a portion of the light reflected by the second reflection surfaces <NUM>.

The light L2 emitted to the guiding body outer part by the transmission surfaces <NUM> is re-incident from the re-incidence surface <NUM> to a guiding body inner part in a case where the second external light blocking part <NUM> is not provided (virtual light L2a). In a case where the virtual light L2a is emitted from the emission surface <NUM> to the vehicle front side, virtual light L2a is projected to the region PB in the vicinity of the H-H line in the overhead pattern P2. In this embodiment, the second external light blocking part <NUM> is provided, and therefore light projected to the region PB is reduced. Therefore, it is possible to suppress generation of glare light in the vicinity of the H-H line.

<FIG> is a diagram illustrating an example of a vehicular lamp unit <NUM> according to this embodiment. <FIG> illustrates an example viewed from the front side in the onboard state. The vehicular lamp unit <NUM> illustrated in <FIG> has a housing <NUM>, an outer lens <NUM>, light sources <NUM>, and a plurality of vehicular light-guiding bodies <NUM>. Herein, the vehicular lamp unit <NUM> has a configuration in which the two vehicular light-guiding bodies <NUM> are disposed in a lamp chamber surrounded by the housing <NUM> and the outer lens <NUM>, for example. The number of the vehicular light-guiding bodies <NUM> to be disposed in the lamp chamber may be one or three or more. The arrangement of the vehicular light-guiding bodies <NUM> is not limited to the arrangement in which the vehicular light-guiding bodies <NUM> are disposed side by side in the left-right direction as viewed from the front. The vehicular light-guiding bodies <NUM> may be disposed side by side in the up-down direction, may be disposed side by side in the oblique direction, or may be disposed side by side in a state in which at least two of the left-right direction, the up-down direction, and the oblique direction are combined. For different vehicular light-guiding bodies <NUM>, the number and the arrangement of the light sources <NUM> may be different.

For example, one of the vehicular light-guiding bodies <NUM> may have a configuration for condensing in which the light sources <NUM> are disposed such that light is incident on the central incidence surfaces <NUM>, and the other vehicular light-guiding body <NUM> may have a configuration for diffusion in which the light sources <NUM> are disposed such that light is incident on the outer incidence surfaces 21N. A plurality of the vehicular light-guiding bodies each having at least one of the configuration for condensing and the configuration for diffusion may be provided. In this case, while heat generated from each vehicular light-guiding body <NUM> is suppressed, a condensing pattern P1a and a diffusion pattern P1b can be formed in front of a vehicle, as the whole vehicular lamp unit <NUM>.

As described above, the vehicular light-guiding body <NUM> according to this embodiment includes: the incidence surfaces <NUM> on which light from the light sources <NUM> are incident; the first reflection surfaces <NUM> that internally reflect the light incident from the incidence surfaces <NUM> and convert the light into substantially parallel light; the second reflection surfaces <NUM> that internally reflect, forward in the front-rear direction in the onboard state, the substantially parallel light from the first reflection surfaces <NUM>; the light blocking part <NUM> that blocks a portion of the light reflected by the second reflection surfaces <NUM>; the connecting surface <NUM> that connects the second reflection surfaces <NUM> and the light blocking part <NUM>, and has the transmission surfaces <NUM> which transmit a portion of the light reflected by the second reflection surfaces <NUM> from the lower side in the up-down direction on the onboard state to the guiding body outer part, and directs the light forward in the front-rear direction; and the re-incidence surface <NUM> that is disposed on the front side in the front-rear direction with respect to the transmission surfaces <NUM> and on the lower side in the up-down direction with respect to the light blocking part <NUM>, and allows the light transmitted from the transmission surfaces <NUM> to the guiding body outer part to be re-incident; and, the emission surface <NUM> that emits the light internally reflected by the second reflection surface <NUM>, and the light incident from the re-incidence surface <NUM>.

According to this configuration, a main pattern (low-beam pattern P1) is formed by light that is reflected by the second reflection surfaces <NUM>, that passes through the light blocking part <NUM> or above the light blocking part <NUM>, and that is emitted from the emission surface <NUM>. In addition, another pattern (overhead pattern P2) is formed on the upper side in front of the vehicle by light that is emitted to the guiding body outer part by the transmission surfaces <NUM>, that passes below the light blocking part <NUM>, that is re-incident from the re-incidence surface <NUM>, and that is emitted from the emission surface <NUM>. Thus, a portion of light incident from the incidence surfaces <NUM> is used as light forming the pattern (overhead pattern P2) different from the main pattern (low-beam pattern P1), so that it is possible to improve the utilization efficiency of light.

In the above vehicular light-guiding body <NUM>, the second reflection surfaces <NUM> have the condensing pattern forming surface <NUM> that internally reflects the substantially parallel light such that the substantially parallel light is condensed forward in the front-rear direction, and the transmission surfaces <NUM> are disposed within the region AR where reflected light internally reflected by the condensing pattern forming surface <NUM> passes, as viewed from the up-down direction. Consequently, a portion of the light forming the condensing pattern P1a in the low-beam pattern P1 is used, so that it is possible to form the overhead pattern P2 condensed in front of the vehicle.

In the above vehicular light-guiding body <NUM>, the connecting surface <NUM> has the recessed part <NUM> located on the front side with respect to the transmission surfaces <NUM>, and recessed toward the guiding body inner part, and the inclined surface that is a portion of the recessed part <NUM>, that is provided between the transmission surfaces <NUM> and the light blocking part <NUM> in the connecting surface <NUM> so as to be inclined downward in the up-down direction toward the front side in the front-rear direction, and that internally reflects, forward in the front-rear direction, a portion of the light reflected by the second reflection surface <NUM> is further provided. The light internally reflected on the inclined surface <NUM> passes through a position closer to the light blocking part <NUM>, compared to light internally reflected on the connecting surface <NUM> that is not provided with the inclined surface <NUM>. Accordingly, in a case where the light emits from the emission surface <NUM>, the light is projected to a region closer to the cutoff line CL. Therefore, compared to the case where no inclined surface <NUM> is provided, visibility from a long distance is improved. In this configuration, the inclined surface <NUM> disposed in front of the transmission surfaces <NUM> is provided as a portion of the recessed part <NUM>, so that it is possible to prevent blocking of light transmitted through the transmission surfaces <NUM> and traveling toward the guiding body outer part located on the front side, for example, compared to the case where the inclined surface <NUM> is provided as a portion of the protruding part that protrudes toward the lower side of the connecting surface <NUM>.

In the above vehicular light-guiding body <NUM>, the inclined surface <NUM> has the first external light blocking part <NUM> that is disposed so as to protrude on the guiding body outer part, and blocks a portion of light transmitted from the transmission surfaces <NUM> to the guiding body outer part. In the above vehicular light-guiding body <NUM>, the second external light blocking part <NUM> that is disposed on the front side in the front-rear direction with respect to the transmission surfaces <NUM> in the connecting surface <NUM> so as to protrude on the guiding body outer part, and blocks a portion of light transmitted from the transmission surfaces <NUM> to the guiding body outer part is further provided. In this configuration, light projected to a portion of the region of the pattern (overhead pattern P2) formed on the upper part in front of the vehicle is reduced. Consequently, it is possible to suppress, for example, illusion on the side of a vehicle ahead or on the side of an oncoming vehicle, or suppress the generation of glare light.

In the above vehicular light-guiding body <NUM>, the transmission surfaces <NUM> are disposed on both sides with a space at a central part in the left-right direction in the onboard state. Consequently, light that passes the central part in the left-right direction in the onboard state in the region AR can be used as light that forms the low-beam pattern P1 acting as a main pattern, and light that passes both sides in the left-right direction can be effectively used as another overhead pattern P2. The transmission surfaces <NUM> are disposed with the space on the left and right, so that it is possible to sufficiently obtain left and right diffusion of the overhead pattern P2, and it is possible to suppress excessive rise of the luminous intensity of the central part.

In the above vehicular light-guiding body <NUM>, the emission surface <NUM> projects the diffusion pattern PF toward the front of the vehicle. In this configuration, the diffusion pattern PF can be formed in front of the vehicle while effectively using light by the vehicular light-guiding body <NUM> integrated from the incidence surfaces <NUM> to the emission surface <NUM>.

The vehicular lamp unit <NUM> according to this embodiment includes the light sources <NUM>, and a plurality of the vehicular light-guiding bodies <NUM> that guide and emit light from the light sources <NUM>. According to this configuration, the vehicular lamp unit <NUM> as a whole can obtain the diffusion pattern PF that combines the projection patterns of a plurality of the vehicular light-guiding bodies <NUM>.

The technical scope of the present invention is not limited to the above embodiments, and changes may be made as appropriate without departing from the scope of the present invention which is defined by the appended claims. In the above embodiments, the configuration of the vehicular lamp <NUM> to be mounted on a vehicle that travels on a road with left-hand traffic is described as an example, but the present invention is not limited to this, and the same description is possible when the vehicular headlight can be mounted on a vehicle which travels on a road with right-hand traffic.

Claim 1:
A vehicular light-guiding body comprising:
an incidence surface (<NUM>) on which light from a light source is incident;
a first reflection surface (<NUM>) that internally reflects the light incident from the incidence surface (<NUM>) and converts the light into substantially parallel light;
a second reflection surface (<NUM>) that internally reflects, forward in a front-rear direction, when the vehicular light guiding body is mounted on a vehicle, the substantially parallel light from the first reflection surface (<NUM>);
a light blocking part (<NUM>) that blocks a portion of the light reflected by the second reflection surface (<NUM>);
a connecting surface (<NUM>) that connects the second reflection surface (<NUM>) and the light blocking part (<NUM>), and has a transmission surface (<NUM>) which transmits a portion of the light reflected by the second reflection surface (<NUM>) from a lower side in an up-down direction, when the vehicular light guiding body is mounted on a vehicle, to a guiding body outer part, and directs the light forward in the front-rear direction;
a re-incidence surface (<NUM>) that is disposed on a front side in the front-rear direction with respect to the transmission surface (<NUM>) and on a lower side in the up-down direction with respect to the light blocking part (<NUM>), and allows the light transmitted from the transmission surface (<NUM>) to the guiding body outer part to be re-incident; and
an emission surface (<NUM>) that emits the light internally reflected by the second reflection surface (<NUM>), and the light incident from the re-incidence surface (<NUM>);
characterized in that
the transmission surface (<NUM>) includes transmission surfaces (<NUM>) which are disposed on both sides of the vehicular light-guiding body with a space at a central part in a left-right direction when the vehicular light guiding body is mounted on a vehicle.