JP3391143B2 - Vehicle lighting - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a virtual reflection surface set on an inner surface of a housing for mounting and holding a valve, and a vertical direction and a horizontal direction are set along the virtual reflection surface. A plurality of diffusion prisms extending in one direction and having a curved reflection surface defining a diffusion angle are formed in a stepwise manner, and are orthogonal to the direction in which the diffusion prism extends to the front lens mounted on the front surface of the housing. The present invention relates to an improvement in a vehicular lamp in which diffusion prisms extending long in a direction are formed in parallel. 2. Description of the Related Art Conventionally, as shown in FIGS. 1 and 2, a lamp chamber 3 is formed by mounting a front lens 2 extending long in a lateral direction on a housing 1, and a bulb 4 is mounted on the housing 1. A virtual reflection surface S is set on the inner surface of the housing 1 so as to be mounted and held, and a plurality of step-like diffusion prisms 5 extending longitudinally along the virtual reflection surface S (FIG. 3).
Look at the reference) from the front of the front lens 2 is formed at an equal pitch p, the plurality of diffusion prism 6 or or elongated in the transverse direction pot <br/> This shape of the inner surface of the front lens 2 front lens 2 A vehicular lamp formed at an equal pitch when viewed from the front of a vehicle is known. The diffusion prism 5 has a curved reflection surface 5a for defining a diffusion angle. This curved anti-slope surface 5a is formed of an arc-shaped convex curved surface. The light beam q emitted from the light spot 4a of the bulb 4 on the optical axis O of the virtual reflection surface S is reflected on each curved reflection surface 5a.
And the maximum reflection angle θ is defined by an angle between a parallel line r parallel to the optical axis O and the light beam q ′ reflected by the vertex 5b of the curved reflection surface 5a. [0004] However, in this conventional vehicle lamp, as shown in FIG. 3, light rays P in a hatched area toward a certain diffusion prism 5i are curved and reflected by an adjacent diffusion prism 5i '. The base point 5 of the reflection surface 5a of the diffusion prism 5i is shielded from light by a portion near the vertex 5b of the surface 5a.
c, that is, the vicinity of the base point 5c of the reflection surface 5a of the diffusion prism 5i is
Since the shadow in the vicinity of the vertex 5b of i ′ is a shadow of the virtual reflection surface S in FIG. 3 when the inside of the lamp room 3 of the vehicular lamp is viewed from the arrow X direction corresponding to the maximum reflection angle direction. There is an inconvenience that the right half looks brighter with respect to the axis O but the left half looks relatively darker. Conversely, when the vehicular lamp is viewed from the direction of the arrow X ′ corresponding to the maximum reflection angle direction, the left half looks bright with respect to the optical axis O of the virtual reflection surface S, but the right half is relatively bright. Looks dark. Therefore, in the conventional vehicular lamp, when the front lens 2 is viewed from the direction of the maximum reflection angle, only one side looks bright with the optical axis O of the virtual reflection surface S as a boundary, and the other side is relatively dark. look, there is a problem that the appearance on the undesirable. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicular lamp in which the entire virtual reflection surface shines even when the front lens is viewed from the maximum reflection angle direction. Is to provide. [0007] A vehicle lamp according to the present invention comprises:
In order to solve the above problem, a virtual reflection surface is set on the inner surface of the housing, and has a curved reflection surface that extends along the virtual reflection surface in one of the vertical direction and the horizontal direction and defines a diffusion angle. A plurality of diffusion prisms are formed between a plurality of virtual parabolas, and a lens-side diffusion prism that extends long in a direction orthogonal to a direction in which the diffusion prism extends is formed in parallel with a front lens mounted on the front surface of the housing, The diffusion prism has a vertex that is one end of the curved reflection surface disposed on the virtual parabola, and reflects a ray from a light point toward a maximum reflection angle direction on one side with a parallel line parallel to the optical axis as a boundary. is set to the other end and name Ru reflection point of the curved reflecting surface is from and light spots are disposed on an extension line of the light beam from the light spot towards the apex of the other of the diffusion prism adjacent to the reflective point side light Together with is set so as to reflect toward the maximum reflection angle direction of the other side the boundary of the optical axis and parallel to parallel lines, wherein the vertex of the reflection point and the previous SL other diffusion prism is continuously linearly It is characterized by being. According to the vehicular lamp according to the present invention, the curved reflecting surface of each diffusing prism causes the light beam emitted from the light spot to be on one side with a parallel line parallel to the optical axis of the virtual reflecting surface as a boundary. In the direction of the maximum reflection angle, and also in the direction of the maximum reflection angle on the other side. Therefore, even when the front lens is viewed from the direction of the maximum reflection angle, the entire virtual reflection surface appears to shine. FIG. 4 shows a housing 10 and S shows FIG.
O is the optical axis of the virtual reflection surface S,
1 is a light spot of the bulb 4 existing on the optical axis O, 12 is a vertex of the virtual reflection surface S, and 13 is a diffusion prism which defines a diffusion angle. Here, the virtual reflection surface S is formed of a paraboloid, but may be any one of a spherical surface and a flat surface. Light spot 1
1 is provided at the position of the focal point F of the virtual reflection surface S,
Are reflected light parallel to the optical axis O, assuming that the diffusion prism 13 is not provided. Diffusion prism 13
Are formed symmetrically in a stepwise manner with respect to the optical axis O of the virtual reflection surface S. Each base point 13a of the diffusion prism 13 exists on the virtual reflection surface S and on a virtual parabola 14 having an appropriate focus, and each vertex 13b exists on a virtual parabola 14 having an appropriate focus. As shown in an enlarged manner in FIG. 5, a light beam q1 from a light point 11 toward a vertex 13b of one of the diffusion prisms 13 adjacent to one another among the diffusion prisms 13 is separated by a parallel line 15 parallel to the optical axis O on the other side. Is reflected toward the maximum reflection angle direction q1 ′, and the light ray q2 obtained by extending the light ray q1 to the other diffusion prism 13 is the maximum reflection angle direction q2 on one side of the parallel line 15 by the other diffusion prism 13. The curved reflection surface 13c is formed so as to be reflected toward '. Assuming that a reflection point at which the light beam q2 is reflected by the curved reflection surface 13c is 13d, an area from the reflection point 13d of the diffusion prism 13 to the base point 13a is an invalid reflection area 13e. The invalid reflection area 13e from the reflection point 13d to the base point 13a is a straight line here. When the curved reflecting surface 13c of the diffusing prism 13 is formed in this way, the diffusing prism 13 is visually observed from the front of the front lens 2 due to the bending at the reflecting point 13d between the curved reflecting surface 13c and the ineffective reflecting region 13e. In this case, a streak extending from the reflection point 13d in the vertical direction is visible . Therefore , the reflection point 13 of the curved reflection surface 13c
If the invalid reflection area 13e is formed so as to extend tangentially to d, the streak can be made invisible. Alternatively, the streak may be made invisible by smoothly connecting the invalid reflection area 13e to the reflection point 13d. FIG. 6 shows an embodiment of such a diffusion prism 13. Since the portion of the invalid reflection area 13e may or may not be originally present, one of the adjacent diffusion prisms 13 is provided. Is connected linearly from the reflection point 13d of the diffusion prism 13 to the vertex 13b of the other diffusion prism 13. According to the present invention, the curved reflecting surface 13c of each diffusion prism 13 converts the light beam emitted from the light spot 11 into a maximum on one side with respect to a parallel line 15 parallel to the optical axis O of the virtual reflecting surface S. The light is reflected in the direction of the reflection angle, and is also reflected in the direction of the maximum reflection angle on the other side. Therefore, even when the front lens 2 is viewed from the maximum reflection angle direction, the entire virtual reflection surface S appears to shine. In each of the embodiments described above, the curved reflecting surface of the diffusion prism is described as being convex, but the curved reflecting surface of the diffusion prism may be formed concave. Further, a configuration in which a convex curved reflecting surface and a concave reflecting surface are mixed may be employed. The vehicle lighting device according to the present invention is constructed as described above. Therefore, even when the front lens is viewed from the direction of the maximum reflection angle, the entire virtual reflection surface appears to shine. To play.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view showing a schematic configuration of a conventional vehicle lamp. FIG. 2 is a front view of a conventional vehicle lamp. FIG. 3 is a sectional view of a main part of a housing of the vehicular lamp shown in FIGS. 1 and 2; FIG. 4 is a cross-sectional view showing a configuration of a main part of the housing of the present invention. FIG. 5 is a partially enlarged sectional view of the diffusion lens of FIG. 4; FIG. 6 is a view showing an embodiment of the diffusion lens shown in FIG. [Description of Signs] 10 ... Housing 11 ... Light spot 13 ... Diffusion prism 13b ... Vertex 13c ... Curved reflection surface 13e ... Reflection point 15 ... Parallel line O ... Optical axis S ... Virtual reflection surface θ ... Reflection angle

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F21S 8/10-8/12

Claims (1)

(57) [Claim 1] A virtual reflection surface is set on an inner surface of a housing, extends along the virtual reflection surface in one of a vertical direction and a horizontal direction, and reduces a diffusion angle. A plurality of diffusion prisms having a curved reflecting surface to be defined are formed between a plurality of virtual parabolas, and a lens-side diffusion prism that extends long in a direction orthogonal to a direction in which the diffusion prism extends in a front lens mounted on a front surface of the housing. Are formed in parallel, and the apex, which is one end of the curved reflecting surface, is disposed on the virtual parabola, and the light from the light point is maximally divided on one side by a parallel line parallel to the optical axis. is set to reflect toward the reflection angle direction, the light reflection point and the other end of the curved reflecting surface <br/> ing is directed to <br/> vertex of another diffusion prism adjacent to the reflective point side Placed on the extension of the ray from the point And while being set to reflect toward the boundary of the optical axis and parallel to parallel lines in the maximum reflection angle direction of the other side light rays from the light spot, and the vertices of the reflection point and the previous SL other diffusion prism A vehicular lamp characterized by being linearly continuous.