JP2009238469A - Projection lens for lamp, optical unit for vehicle, and lamp for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection lens for a lamp of a prescribed shape, which can control light emitted from an emitting face even in a horizontal direction. <P>SOLUTION: The projection lens for the lamp is provided with at least an incident face, an emitting face, and a first side face and a second side face mutually facing each other, and forms a prescribed light distribution pattern below a horizontal line. Each of the first side face and the second side face is a total reflection face constructed of a free-form surface having a plurality of minute reflecting surfaces as a base, and each of the plurality of minute reflecting surfaces is a reflecting surface which is formed so as to reflect an incident light toward the vicinity of a prescribed light source, when the light parallel to horizontal face including the optical axis of a convex lens emitted from a prescribed part in the prescribed light distribution pattern is made to enter the lens from the emitting face. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a projection lens for a lamp, an optical unit for a vehicle, and a vehicular lamp, and in particular, has a predetermined shape (incident surface, emission surface, and each other) that can control light emitted from the emission surface even in the horizontal direction. The present invention relates to a projection lens for a lamp (having first and second side surfaces facing each other), a vehicular optical unit using the projection lens for the lamp, and a vehicular lamp.

  Conventionally, a projection lens for a lamp having an incident surface, an exit surface, and a first side surface and a second side surface facing each other has been proposed (see, for example, Patent Document 1).

  FIG. 9 is a perspective view for explaining the projection lens for a lamp described in Patent Document 1. FIG.

  As shown in FIG. 9, the projection lens for a lamp described in Patent Document 1 includes an incident surface 11 ′ as a rear surface, an exit surface 12 ′ as a front surface, a first side surface 13R ′ and a second side surface 13L ′ as both side surfaces. The first side surface 13R ′ and the second side surface 13L ′ are formed as vertical planes, and the distance between the first side surface 13R ′ and the second side surface 13L ′ is about 10 to 15 mm.

In the projection lens for a lamp described in Patent Document 1, direct light incident on the inside of the lens from a predetermined light source 20 ′ and directly directed to the emission surface 12 ′ and once with the first side surface 13R ′ and the second side surface 13L ′ or The reflected light that has been reflected a plurality of times and directed toward the emission surface 12 ′ is emitted from the emission surface 12 ′, and forms a predetermined light distribution pattern P ′ as shown in FIG. 10, for example.
JP-T-2006-522439

  However, since both the first side surface 13R ′ and the second side surface 13L ′ are vertical planes, the light emitted from the emission surface 12 ′ can be collected in the vertical direction, but controlled in the horizontal direction. I can't. For this reason, the light distribution in the horizontal direction is almost determined by the directivity of the predetermined light source 20 ', and there is a problem that it is difficult to form a desired light distribution pattern.

  The present invention has been made in view of such circumstances, and has a predetermined shape (the incident surface, the exit surface, and the first facing each other) that can control light emitted from the exit surface even in the horizontal direction. It is an object of the present invention to provide a projection lens for a lamp having a side surface and a second side surface, and an optical unit for a vehicle and a vehicle lamp using the projection lens for the lamp.

  In order to solve the above-mentioned problem, the invention according to claim 1 includes at least an incident surface, an exit surface, a first side surface and a second side surface facing each other, and a predetermined light source incident on the inside of the lens from the incident surface. Of the incident light, direct light directed to the output surface and reflected light reflected by the first and second side surfaces and directed to the output surface are emitted from the output surface, and a predetermined light distribution pattern is formed below the horizontal line. In the projection lens for a lamp to be formed, the incident surface is a surface for allowing light from a predetermined light source to enter the lens, and the exit surface is a convex lens surface that is a part of the exit surface of the aspheric projection lens. And an exit surface in which a curved focal line is set in a horizontal plane opposite to the convex lens surface and including the optical axis of the convex lens, and each of the first side surface and the second side surface is based on a plurality of minute reflecting surfaces. A free-form surface Each of the plurality of micro-reflective surfaces is a light beam emitted from a predetermined location in the predetermined light distribution pattern and parallel to a horizontal plane including the optical axis of the convex lens. It is a reflecting surface formed so as to reflect the incident light beam toward the vicinity of the predetermined light source when entering the lens from the exit surface.

  According to the first aspect of the present invention, the first side surface and the second side surface are not flat surfaces as in the prior art, but are free-form surfaces (horse-shaped) based on a plurality of minute reflecting surfaces (also referred to as minute reflecting points). It is a total reflection surface constituted by a curved surface. Each of the plurality of micro-reflecting surfaces enters a light beam (for example, a virtual light beam parallel to a horizontal plane including the optical axis of the lens) emitted from a predetermined position in a predetermined light distribution pattern from the output surface into the lens. In this case, the incident light beam is reflected toward the vicinity of the predetermined light source.

  Therefore, according to the first aspect of the present invention, the first reflection surface and the second reflection surface are reflected, and the light emitted from the emission surface (incident light from the predetermined light source) is also controlled in the horizontal direction. It becomes possible.

  That is, according to the first aspect of the present invention, the light emitted from the emission surface is also controlled in the horizontal direction, and has a predetermined shape (incident surface, emission surface, It is possible to provide a projection lens for a lamp (having first and second side surfaces facing each other).

  The first side surface and the second side surface as free curved surfaces based on the plurality of minute reflecting surfaces are not flat surfaces as in the prior art, but horseshoe-shaped free curved surfaces.

  In the first aspect of the present invention, the incident light from the predetermined light source that is incident on the inside of the lens and reflected by the first side surface and the second side surface (a plurality of minute reflecting surfaces) is as if it has a curved focal point. The same state as that emitted from a point on the line is obtained.

  Therefore, according to the first aspect of the present invention, even if a shutter is arranged between the predetermined light source and the incident surface, the mirror image of the shutter does not become a blurred image as in the prior art, but from the horizontal line. Also, a sharp image projected below is formed, and it is possible to form a predetermined light distribution pattern below the horizontal line (correction of field curvature).

  According to the first aspect of the present invention, the width dimension (distance between the first side surface and the second side surface) and the depth dimension (distance and angle between the entrance surface and the exit surface) are set to the first side surface and the second side surface. By setting the dimension of the side surface to reflect the incident light from the predetermined light source only once toward the output surface, it is possible to prevent or reduce the occurrence of uneven light distribution in the horizontal direction.

  The invention according to claim 2 is the invention according to claim 1, wherein the exit surface is a left-right symmetric or left-right asymmetric convex lens surface that is a part of the exit surface of the aspherical projection lens. .

  This is an example of the exit surface.

  According to the second aspect of the present invention, if a left-right symmetric or left-right asymmetric convex lens surface, which is a part of the output surface of the aspherical projection lens, is used as the output surface, it is possible to provide a new-looking lens for a lamp. It becomes possible. Further, for example, if a left-right asymmetric convex lens surface that is a part of the exit surface of the aspherical projection lens is used as the exit surface, the lamp lens is almost compared to a lamp lens using a left-right symmetrical convex lens surface. A light distribution pattern having a desired light intensity distribution can be formed without tilting.

  The invention described in claim 3 includes at least an incident surface, an exit surface, and a first side surface and a second side surface facing each other, and out of the incident light from a predetermined light source that enters the lens from the incident surface. In a projection lens for a lamp that emits direct light toward a surface and reflected light that is reflected by the first side surface and the second side surface and is directed toward the exit surface from the exit surface, and forms a predetermined light distribution pattern below a horizontal line. The incident surface is a surface on which light from a predetermined light source is incident inside the lens, and each of the first side surface and the second side surface has a cross-sectional shape that appears when cut by a surface orthogonal to the lens optical axis inside the lens. A horseshoe that is formed so that it has a concave curve that is concave toward the surface, and a cross-sectional shape that appears when it is cut along a plane that includes the optical axis of the lens and a plane that is parallel to this plane, is a convex curve that bulges toward the outside of the lens. All of mold A morphism surface, the exit surface, characterized in that it is a convex lens surface of the convex lens surface or a cylindrical lens, which is part of the exit surface of the aspherical projection lens.

  According to the invention described in claim 3, each of the first side surface and the second side surface is not a flat surface as in the prior art, but a horseshoe-shaped total reflection surface.

  Therefore, according to the third aspect of the present invention, the first reflection surface and the second reflection surface are reflected, and the light emitted from the emission surface (incident light from the predetermined light source) is also controlled in the horizontal direction. It becomes possible.

  That is, according to the third aspect of the present invention, the light emitted from the emission surface is also controlled in the horizontal direction, and has a predetermined shape (incident surface, emission surface, It is possible to provide a projection lens for a lamp (having first and second side surfaces facing each other).

  According to a fourth aspect of the present invention, there is provided a projection lens having at least an entrance surface, an exit surface, a first side surface and a second side surface facing each other, and a state in which the optical axis direction is substantially matched with the optical unit optical axis direction. An LED light source that emits light that is incident on the projection lens, and a shutter that is disposed between the projection lens and the LED light source, from the LED light source that has entered the lens from the incident surface. Out of the incident light, direct light directed to the exit surface and reflected light reflected by the first and second side surfaces and directed to the exit surface are emitted from the exit surface, and a predetermined light distribution pattern is formed below the horizontal line. In the vehicular optical unit, the incident surface is a surface on which light from a predetermined light source enters the lens, and the exit surface is a convex lens surface that is a part of the exit surface of the aspheric projection lens. And an exit surface in which a curved focal line is set in a horizontal plane opposite to the convex lens surface and including the optical axis of the convex lens, and each of the first side surface and the second side surface is based on a plurality of minute reflecting surfaces. Each of the plurality of micro-reflecting surfaces is parallel to a horizontal plane including the optical axis of the convex lens, which is emitted from a predetermined location in the predetermined light distribution pattern. When the light beam is incident on the inside of the lens from the exit surface, the light beam is a reflective surface formed so as to reflect the incident light beam toward the vicinity of the LED light source.

  According to the invention described in claim 4, the first side surface and the second side surface are not flat surfaces as in the prior art, but are free-form surfaces (horse-shaped) based on a plurality of minute reflecting surfaces (also referred to as minute reflecting points). It is a total reflection surface constituted by a curved surface. Each of the plurality of micro-reflecting surfaces enters a light beam (for example, a virtual light beam parallel to a horizontal plane including the optical axis of the lens) emitted from a predetermined position in a predetermined light distribution pattern from the output surface into the lens. In this case, the incident light beam is formed to be reflected toward the vicinity of the LED light source.

  Therefore, according to the fourth aspect of the present invention, the first reflection surface and the second reflection surface are reflected, and the light emitted from the emission surface (incident light from the predetermined light source) is also controlled in the horizontal direction. It becomes possible.

  That is, according to the fourth aspect of the present invention, the light emitted from the emission surface is also controlled in the horizontal direction, and has a predetermined shape (incident surface, emission surface, It is possible to provide a vehicular optical unit using a lamp projection lens (having first and second side surfaces facing each other).

  The first side surface and the second side surface as free curved surfaces based on the plurality of minute reflecting surfaces are not flat surfaces as in the prior art, but horseshoe-shaped free curved surfaces.

  In the invention according to claim 4, the incident light from the LED light source incident on the inside of the lens and reflected by each of the first side surface and the second side surface (a plurality of minute reflecting surfaces) is as if it is a curved focal point. The same state as that emitted from a point on the line is obtained.

  Therefore, according to the fourth aspect of the present invention, even if a shutter is disposed between the LED light source and the incident surface, the mirror image of the shutter is not a blurred image as in the prior art, but from the horizontal line. Also, a sharp image projected below is formed, and it is possible to form a predetermined light distribution pattern below the horizontal line (correction of field curvature).

  According to the fourth aspect of the present invention, the width dimension (distance between the first side surface and the second side surface) and the depth dimension (distance and angle between the incident surface and the exit surface) are set to the first side surface and the second side surface. By setting the side surface to a size that reflects the incident light from the LED light source only once toward the output surface, it is possible to prevent or reduce the occurrence of uneven light distribution in the horizontal direction.

  According to a fifth aspect of the present invention, in the invention according to the fourth aspect, the shutter includes a linear ridge line extending in a horizontal direction in order to form a cut-off line of the predetermined light distribution pattern. The distance between the shutter and the incident surface is set within 1 mm.

  According to the fifth aspect of the invention, since the distance between the shutter and the incident surface is set within 1 mm, it is possible to improve the utilization efficiency of the light emitted from the LED light source. In addition, it is possible to reduce the influence of heat generated by the light emission of the LED light source on the incident surface.

  According to a sixth aspect of the invention, in the invention of the fourth or fifth aspect, the shutter is a shutter formed by a painted surface or a vapor deposition surface formed on the incident surface.

  According to the invention described in claim 6, since the shutter is formed by painting or vapor-depositing on the incident surface, a separate shutter is not required. Further, the depth dimension of the optical unit for vehicles can be reduced by the thickness of the shutter.

  A seventh aspect of the present invention is a vehicular lamp configured by the vehicular optical unit according to any one of the fourth to sixth aspects.

  According to the invention described in claim 7, the first side surface and the second side surface are not flat surfaces as in the prior art, but are free-form surfaces (horse-shaped) based on a plurality of minute reflecting surfaces (also referred to as minute reflecting points). It is a total reflection surface constituted by a curved surface. Each of the plurality of micro-reflecting surfaces enters a light beam (for example, a virtual light beam parallel to a horizontal plane including the optical axis of the lens) emitted from a predetermined position in a predetermined light distribution pattern from the output surface into the lens. In this case, the incident light beam is formed to be reflected toward the vicinity of the LED light source.

  Therefore, according to the seventh aspect of the invention, the light reflected from the first reflecting surface and the second reflecting surface and emitted from the emitting surface (incident light from the predetermined light source) is also controlled in the horizontal direction. It becomes possible.

  That is, according to the seventh aspect of the present invention, the light emitted from the emission surface is also controlled in the horizontal direction to have a predetermined shape (incident surface, emission surface, It is possible to provide a vehicular lamp using a lamp projection lens (having first and second side surfaces facing each other).

  The first side surface and the second side surface as free curved surfaces based on the plurality of minute reflecting surfaces are not flat surfaces as in the prior art, but horseshoe-shaped free curved surfaces.

  In the invention according to claim 7, the incident light from the LED light source that is incident on the inside of the lens and is reflected by each of the first side surface and the second side surface (a plurality of minute reflecting surfaces) is as if it has a curved focal point. The same state as that emitted from a point on the line is obtained.

  For this reason, according to the seventh aspect of the present invention, even if a shutter is disposed between the LED light source and the incident surface, the mirror image of the shutter is not a blurred image as in the prior art. Also, a sharp image projected below is formed, and it is possible to form a predetermined light distribution pattern below the horizontal line (correction of field curvature).

  According to the seventh aspect of the present invention, the width dimension (distance between the first side surface and the second side surface) and the depth dimension (distance and angle between the incident surface and the exit surface) are set to the first side surface and the second side surface. By setting the side surface to a size that reflects the incident light from the LED light source only once toward the output surface, it is possible to prevent or reduce the occurrence of uneven light distribution in the horizontal direction.

  According to the present invention, the first reflection surface and the second reflection surface reflect, and the light emitted from the emission surface (incident light from the predetermined light source) has a predetermined shape (incident light) that can be controlled even in the horizontal direction. It is possible to provide a projection lens for a lamp having a surface, an exit surface, a first side surface and a second side surface facing each other, and an optical unit for a vehicle and a vehicle lamp using the projection lens for the lamp. .

  Hereinafter, an optical unit for a vehicle using a lamp lens according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view for explaining a main configuration of a vehicular optical unit (or vehicular lamp) using the lamp lens of the present embodiment. FIG. 2 is a top view of the vehicle optical unit shown in FIG.

  The vehicular optical unit 100 using the projection lens 10 as the lamp lens of the present embodiment is applied to a vehicular lamp such as a headlamp of a vehicle such as an automobile, and is shown in FIGS. 1 and 2. Are provided with a projection lens 10, an LED light source 20, a shutter 30 disposed between the projection lens 10 and the LED light source 20, a heat sink 40, and the like.

  As shown in FIGS. 1 and 2, the projection lens 10 has a projection surface including an incident surface 11 as a front surface, an output surface 12 as a back surface, and a first side surface 13R and a second side surface 13L facing each other as both side surfaces. It is a lens (collimating lens), and is arranged in a state where its optical axis is substantially coincident with the lamp optical axis AX. The projection lens 10 is formed, for example, by injection molding a transparent or translucent material such as acrylic or polycarbonate.

  The incident surface 11 is an incident surface (for example, a flat surface or a curved surface) as an entrance through which the light emitted from the LED light source 20 enters the projection lens 10.

  As shown in FIG. 3, the exit surface 12 is a symmetrical convex lens surface conceptually cut out from the aspheric projection lens L (a convex lens surface corresponding to a part of the convex lens surface as the exit surface of the aspheric projection lens L). As shown in FIG. 2, a curved focal line L1 is set in the vicinity of the incident surface 11 on the opposite side of the convex lens surface and on a horizontal plane including the optical axis of the convex lens. Further, as shown in FIG. 7, the exit surface 12 has a curved focal line L2 in a vertical section.

  As shown in FIG. 2, the first side surface 13R and the second side surface 13L are reflection surfaces that reflect incident light from the LED light source 20 only once toward the emission surface 12, and include a plurality of minute reflection surfaces M1, M2, M3,... M1 ′, M2 ′, M3 ′, etc. (which may also be referred to as minute reflection points) are total reflection surfaces constituted by free-form surfaces. An interval between the first side surface 13R and the second side surface 13L can be set to an appropriate interval (for example, 10 to 15 mm).

  As shown in FIG. 2, the width dimension b, depth dimension d, and angle of the projection lens 10 are such that the first side surface 13R and the second side surface 13L reflect incident light from the LED light source 20 only once toward the output surface 12. Is set to the dimension you want. FIG. 2 shows an example of the projection lens 10 in which the width dimension b is set to 15 mm and the depth dimension d is set to 48 mm.

  For this reason, in the projection lens 10, the incident light (the mirror image of the shutter 30 or the light source image of the LED light source 20) emitted from the LED light source 20 emitted from the emission surface 12 is not reflected more than once (the mirror image of the shutter 30). Or, the number of repeated reflections of the light source image of the LED light source 20 does not change). As a result, it is possible to prevent or reduce the occurrence of uneven light distribution in the horizontal direction.

  Each of the plurality of minute reflecting surfaces M1, M2, M3,... M1 ′, M2 ′, M3 ′,..., As shown in FIG. Light rays (virtual rays parallel to the horizontal plane including the optical axis of the projection lens 10) emitted from the predetermined positions PR and PL on the left and right sides in the light distribution pattern P are incident on the projection lens 10 from the emission surface 12. In this case, the incident light beam is formed to be reflected toward the vicinity of the LED light source 20.

  The first side surface 13R and the second side surface 13L as free curved surfaces based on the plurality of minute reflecting surfaces M1, M2, M3... M1 ′, M2 ′, M3 ′. Instead, it is a horse-shaped curved surface.

  That is, the first side surface 13R and the second side surface 13L as free curved surfaces based on the plurality of minute reflecting surfaces M1, M2, M3... M1 ′, M2 ′, M3 ′. As shown in FIG. 2, the cross-sectional shape that appears when cut along a vertical plane orthogonal to the optical axis of the projection lens 10 is a concave curve that is recessed toward the inside of the projection lens 10, and as shown in FIG. A cross-sectional shape that appears when cutting along a horizontal plane that includes the optical axis and a horizontal plane that is parallel to the horizontal plane is a convex curve that bulges toward the outside of the projection lens 10, and as a whole, a curved surface having a horseshoe shape.

  As described above, the first side surface 13R and the second side surface 13L are not flat surfaces as in the prior art, but are based on a plurality of minute reflecting surfaces M1, M2, M3... M1 ′, M2 ′, M3 ′. It is a horse-shaped curved surface that is a free curved surface. The first side surface 13R and the second side surface 13L can control the light emitted from the emission surface 12 (incident light from a predetermined light source) also in the horizontal direction.

  Further, the light enters the inside of the projection lens 10 and is reflected by the first side surface 13R and the second side surface 13L (a plurality of minute reflecting surfaces M1, M2, M3..., M1 ′, M2 ′, M3 ′...). Incident light from the LED light source 20 is in the same state as if it was emitted from a point on the focal line L1.

  For this reason, even if the shutter 30 is disposed between the LED light source 20 and the incident surface 11, the mirror image of the shutter 30 is not a blurred image as in the prior art, but is projected below the horizontal line H. For example, as shown in FIG. 5, it is possible to form a predetermined light distribution pattern P below the horizontal line H (correction of field curvature) as shown in FIG. 5.

  The LED light source 20 is, for example, an LED package in which one (or plural) LED chips of single color or RGB three colors are packaged. As shown in FIG. 2, the LED light source 20 is disposed in a state where its optical axis substantially coincides with the lamp optical axis AX and its light emitting surface faces the incident surface 11 of the projection lens 10.

  The shutter 30 is for blocking a part of light incident on the projection lens 10 from the LED light source 20 to form a cut-off line of a predetermined light distribution pattern. For example, the shutter 30 is a linear ridge line extending in the horizontal direction ( (Not shown). The interval between the shutter 30 and the incident surface 11 is preferably set within 1 mm in relation to the utilization efficiency of light from the LED light source 20. Alternatively, the shutter 30 may be formed as a painted surface or a vapor deposition surface on the incident surface 11 by painting or vapor deposition. In this way, a separate shutter 30 is unnecessary. Further, the depth dimension of the vehicle optical unit 100 can be reduced by the thickness of the shutter 30.

  The heat sink 40 is for dissipating heat generated by the light emission of the LED light source 20, and is disposed, for example, on the back surface of the circuit board K on which the LED light source 20 is mounted.

  Next, a design procedure for the projection lens 10 will be described.

  First, the incident surface 11 as a back surface is a predetermined surface, and the exit surface 12 as a front surface is a convex lens surface (a curved focal line L1 is set on a horizontal plane near the incident surface 11 and including the optical axis of the projection lens 10). An aspherical collimating lens that is a convex lens surface).

  Next, as shown in FIG. 6, the first focal point F <b> 1 is determined, and the longitudinal section of the emission surface 12 is determined.

  Next, as shown in FIG. 4, a range of light (incident light from the LED light source 20) that is not reflected by the first side surface 13 </ b> R and the second side surface 13 </ b> L but directly toward the emission surface 12 is determined. That is, the width of the emission surface 12 is determined. For example, as shown in FIG. 2, the width dimension b and the depth dimension d of the projection lens 10 are such that the first side surface 13R and the second side surface 13L reflect the incident light from the LED light source 20 toward the output surface 12 only once. Set to the dimension you want. Hereinafter, the light (incident light from the LED light source 20) that directly faces the emission surface 12 without being reflected by the first side surface 13R and the second side surface 13L and is emitted from the emission surface 12 is referred to as primary light (direct light).

  Next, light (incident light from the LED light source 20) connected to the range irradiated with the primary light is controlled by the first side surface 13R and the second side surface 13L. For example, as shown in FIG. 4, the light (incident light from the LED light source 20) connected to the right side of the primary light is controlled by the second side surface 13L (a plurality of minute reflecting surfaces M1, M2, M3...) The light connected to the left side of the light (incident light from the LED light source 20) is controlled by the first side surface 13R (a plurality of minute reflecting surfaces M1 ′, M2 ′, M3 ′...).

  At that time, a second focal point F2 is formed in the vicinity of the emission surface 12. By moving the position of the focal point F2 to a predetermined position, the range of the entire left and right light (incident light from the LED light source 20) and the overlap with the primary light are adjusted, and a desired light distribution pattern is obtained. To be formed.

  As shown in FIG. 2, the exit surface 12 of the projection lens 10 has a curved focal line L1 set on a horizontal plane including the optical axis of the lens 10. As shown in FIG. A curved focal line L2 is set.

  However, the light reflected by the first side surface 13R and the second side surface 13L (incident light from the LED light source 20) is a mirror image. Therefore, for example, when the vertical cross sections of the first side surface 13R and the second side surface 13L that are both side surfaces are straight lines (when the first side surface 13R and the second side surface 13L are flat surfaces as in the prior art), FIG. As shown, the mirror image I of the shutter 30 disposed near the LED light source 20 does not coincide with the focal line L1. For this reason, the mirror image I of the shutter 30 is projected as a blurred image.

  For example, when the horizontal cut-off line is formed using the first side surface 13R and the second side surface 13L which are flat surfaces as in the conventional case, the light emitted from the emission surface 12 (incident light from the LED light source 20) is the horizontal line H. Head up and down. For this reason, as shown in FIG. 10, the light distribution pattern protrudes above the horizontal line H.

  In this case, as viewed from the side, the light reflected on the lower side (incident light from the LED light source 20) is directed upward from the horizontal line H, and the light reflected on the upper side (incident light from the LED light source 20) is below the horizontal line H. I know I ’m heading to the side.

  In order to make these lights (the first reflection surface and the second reflection surface reflect and the light emitted from the emission surface 12 gathers in the vicinity of the horizontal line H, for example, the normal line at each position on the vertical section is Tilt according to the position on the vertical section, for example, assuming a virtual shutter having a curved shape (substantially elliptical shape) obtained in consideration of the aberration of the aspherical projection lens L, a plurality of minute reflecting surfaces M1, M2, M3 .., M1 ′, M2 ′, M3 ′... Normal directions are controlled so that the extension lines of the reflected light rays and the ridgelines of the virtual shutter have intersections.

  As a result, light rays (on the horizontal plane including the optical axis of the projection lens 10) emitted from predetermined locations in the predetermined light distribution pattern (for example, predetermined locations PR and PL on both the left and right sides in the predetermined light distribution pattern P shown in FIG. 5). (A virtual light beam parallel to the light source) is incident on the inside of the projection lens 10 from the exit surface 12, a plurality of micro-reflecting surfaces M1, M2, M3... M1 that reflect the incident light beam toward the vicinity of the LED light source 20 ′, M2 ′, M3 ′... (A plurality of minute reflecting surfaces M1, M2, M3..., M1 ′, M2 ′, M3 ′... Corresponding to the respective positions on the longitudinal section) are formed. .

  When all of these minute reflective surfaces M1, M2, M3... M1 ′, M2 ′, M3 ′... Are connected, a plurality of minute reflective surfaces M1, M2, M3. This is a horse-shaped curved surface which is a free curved surface based on M1 ′, M2 ′, M3 ′.

  As described above, according to the projection lens 10 and the vehicle optical unit 100 using the projection lens 10 of the present embodiment, the first side surface 13R and the second side surface 13L are as shown in FIG. Is not a flat surface but a free curved surface (horse-shaped curved surface) based on a plurality of minute reflecting surfaces M1, M2, M3... M1 ′, M2 ′, M3 ′. It is a configured total reflection surface.

  Each of the plurality of minute reflecting surfaces M1, M2, M3,... M1 ′, M2 ′, M3 ′,..., As shown in FIG. A light beam (virtual light beam parallel to the horizontal plane including the optical axis of the projection lens 10) emitted from the left and right predetermined locations PR and PL in the predetermined light distribution pattern P shown in FIG. In this case, the incident light beam is reflected toward the vicinity of the LED light source 20.

  The first side surface 13R and the second side surface 13L as free curved surfaces based on the plurality of minute reflecting surfaces M1, M2, M3... M1 ′, M2 ′, M3 ′. Instead, it is a horse-shaped curved surface.

  That is, the first side surface 13R and the second side surface 13L as free curved surfaces based on the plurality of minute reflecting surfaces M1, M2, M3... M1 ′, M2 ′, M3 ′. As shown in FIG. 2, the cross-sectional shape that appears when cut along a vertical plane perpendicular to the optical axis of the projection lens 10 is a concave curve that is recessed toward the inside of the projection lens 10, and as shown in FIG. And a cross-sectional shape that appears when cut along a horizontal plane parallel to the horizontal plane is a convex curve that bulges toward the outside of the projection lens 10, and as a whole, a curved surface having a horseshoe shape.

  As described above, according to the projection lens 10 and the vehicle optical unit 100 using the projection lens 10 according to the present embodiment, the first side surface 13R and the second side surface 13L are not flat surfaces as in the prior art, but a plurality of minute amounts. Since the reflecting surfaces M1, M2, M3... M1 ′, M2 ′, M3 ′... Are free-form surfaces (horse-shaped curved surfaces), the first reflecting surface 13R and the second reflecting surface 13L are reflected. And it becomes possible to control the light (incident light from LED light source 20) radiate | emitted from the output surface 12 also in a horizontal direction.

  That is, according to the projection lens 10 of this embodiment and the vehicle optical unit 100 using the projection lens 10, the light emitted from the emission surface 12 is also controlled in the horizontal direction to form a desired light distribution pattern. A projection lens 10 for a lamp having a predetermined shape (including an entrance surface, an exit surface, and a first side surface and a second side surface facing each other), a vehicle optical unit 100 using the projection lens 10 for a lamp, and It becomes possible to provide a vehicular lamp.

  Further, according to the projection lens 10 and the vehicle optical unit 100 using the projection lens 10 of the present embodiment, as shown in FIG. 2, the width dimension b and the depth dimension d of the projection lens 10 are the first side surface 13R and The second side surface 13 </ b> L is set to a size that reflects incident light from the LED light source 20 only once toward the output surface 12.

  For this reason, incident light (mirror image of the shutter 30 or light source image of the LED light source 20) emitted from the LED light source 20 emitted from the emission surface 12 is not reflected more than twice (mirror image of the shutter 30 or light source of the LED light source 20). The number of repeated reflections of the image will not change). As a result, it is possible to prevent or reduce the occurrence of uneven light distribution in the horizontal direction.

  Further, according to the projection lens 10 and the vehicle optical unit 100 using the projection lens 10 according to the present embodiment, the light enters the projection lens 10 and the first side surface 13R and the second side surface 13L (a plurality of micro reflective surfaces M1, M2, M3..., M1 ′, M2 ′, M3 ′...)) The incident light from the LED light source 20 is reflected as if it were emitted from a point on the focal line L1. .

  Therefore, according to the projection lens 10 and the vehicle optical unit 100 using the projection lens 10 according to the present embodiment, even if the shutter 30 is disposed between the LED light source 20 and the incident surface 11, the mirror image of the shutter 30 is provided. Does not become a blurred image as in the prior art, but becomes a sharp image projected below the horizontal line H. For example, a predetermined light distribution pattern P is formed below the horizontal line H as shown in FIG. (Correction of curvature of field) is possible.

  Next, a modified example will be described.

  In the above embodiment, as the exit surface 12 of the projection lens 10, as shown in FIG. 3, a symmetrical convex lens surface conceptually cut out from the aspheric projection lens L (on a part of the exit surface of the aspheric projection lens L). Although an example using the corresponding convex lens surface) has been described, the present invention is not limited to this.

  For example, as the exit surface 12 of the projection lens 10, a left-right asymmetric convex lens surface conceptually cut out from the aspheric projection lens L as shown in FIG. 8 (a convex lens surface corresponding to a part of the exit surface of the aspheric projection lens L). ) May be used. In this way, if a left-right asymmetric convex lens surface is used as the exit surface 12, a light distribution pattern having a desired light intensity distribution is obtained without almost tilting the lamp lens as compared with a lamp lens using a left-right symmetrical convex lens surface. Can be formed.

  In the above embodiment, the exit surface 12 is described as being a part of the convex lens surface of the aspherical projection lens L, but the present invention is not limited to this.

  For example, the emission surface 12 may be a part of the convex lens surface of the cylindrical lens. Also in this case, since the first side surface 13R and the second side surface 13L are not flat surfaces as in the prior art, but are horseshoe-shaped curved surfaces, it is possible to control the light emitted from the emission surface 12 even in the horizontal direction. Become.

  The above embodiment is merely an example in all respects. The present invention is not construed as being limited to these descriptions. The present invention can be implemented in various other forms without departing from the spirit or main features thereof.

It is a perspective view for demonstrating the main structures of the optical unit for vehicles to which the lens for lamps of this embodiment was applied. It is a top view of the optical unit for vehicles to which the lens for lamps shown in FIG. 1 was applied. It is the front view which looked at the aspherical projection lens L from the output surface side. 2 is a cross-sectional view for explaining an optical path of incident light from an LED light source 20 that has entered the projection lens 10. FIG. It is an example of the predetermined light distribution pattern formed by the optical unit for vehicles 100 to which the projection lens 10 is applied. 2 is a longitudinal sectional view for explaining an optical path of incident light from an LED light source 20 that has entered the projection lens 10. FIG. It is a figure for demonstrating the focal line L2 of the projection lens 10 (output surface 12). It is a front view of the aspherical convex projection lens L for demonstrating the modification of the projection lens 10 (output surface 12). It is a perspective view of the projection lens of the conventional predetermined shape (it was provided with the entrance surface, the output surface, the 1st side surface and 2nd side surface which faced each other). It is an example of the predetermined light distribution pattern formed with the projection lens of the conventional predetermined shape.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Optical unit for vehicles, 10 ... Projection lens, (Aspherical projection convex lens), 11 ... Incident surface, 12 ... Output surface, 13 ... Incident surface, 13L, 13R ... Side surface, 20 ... LED light source, 30 ... Shutter, 40 ... heat sink, F1, F2 ... focal point, H ... horizontal line, K ... circuit board, L ... aspherical convex projection lens, L1, L2 ... focal line, M1-M3, M1'-M3 '... micro-reflecting surface

Claims (7)

At least an entrance surface, an exit surface, a first side surface and a second side surface facing each other,
Out of incident light from a predetermined light source incident on the inside of the lens from the incident surface, direct light directed to the output surface and reflected light reflected by the first side surface and the second side surface and directed to the output surface are emitted from the output surface. In a projection lens for a lamp that forms a predetermined light distribution pattern below the horizontal line,
The incident surface is a surface that allows light from a predetermined light source to enter the lens,
The exit surface is a convex lens surface that is a part of the exit surface of the aspheric projection lens, and the exit surface has a curved focal line set in a horizontal plane opposite to the convex lens surface and including the optical axis of the convex lens. Surface,
Each of the first side surface and the second side surface is a total reflection surface constituted by a free-form surface based on a plurality of minute reflection surfaces,
Each of the plurality of micro-reflecting surfaces is emitted from a predetermined location in the predetermined light distribution pattern, when a light beam parallel to a horizontal plane including the optical axis of the convex lens is incident on the inside of the lens from the output surface, A projection lens for a lamp, which is a reflecting surface formed so as to reflect the incident light beam toward the vicinity of the predetermined light source.   The projection lens for a lamp according to claim 1, wherein the exit surface is a left-right symmetric or left-right asymmetric convex lens surface that is a part of the exit surface of the aspherical projection lens. At least an entrance surface, an exit surface, a first side surface and a second side surface facing each other,
Out of incident light from a predetermined light source incident on the inside of the lens from the incident surface, direct light directed to the output surface and reflected light reflected by the first side surface and the second side surface and directed to the output surface are emitted from the output surface. In a projection lens for a lamp that forms a predetermined light distribution pattern below the horizontal line,
The incident surface is a surface that allows light from a predetermined light source to enter the lens,
Each of the first side surface and the second side surface has a concave curve in which a cross-sectional shape that appears when cut by a surface orthogonal to the lens optical axis is recessed toward the inside of the lens, and a surface including the lens optical axis and the surface. It is a horseshoe-shaped total reflection surface formed so that the cross-sectional shape that appears when cutting on a parallel surface is a convex curve bulging toward the outside of the lens,
The projection lens for a lamp, wherein the exit surface is a convex lens surface that is a part of the exit surface of an aspheric projection lens or a convex lens surface of a cylindrical lens. A projection lens having at least an entrance surface, an exit surface, a first side surface and a second side surface facing each other;
An LED light source that emits light to be incident on the projection lens, with the optical axis direction substantially aligned with the optical unit optical axis direction;
A shutter disposed between the projection lens and the LED light source,
Of the incident light from the LED light source incident on the inside of the lens from the incident surface, direct light directed to the output surface and reflected light reflected by the first side surface and the second side surface and directed to the output surface are transmitted from the output surface. In the vehicle optical unit that emits and forms a predetermined light distribution pattern below the horizontal line,
The incident surface is a surface that allows light from a predetermined light source to enter the lens,
The exit surface is a convex lens surface that is a part of the exit surface of the aspheric projection lens, and the exit surface has a curved focal line set in a horizontal plane opposite to the convex lens surface and including the optical axis of the convex lens. Surface,
Each of the first side surface and the second side surface is a total reflection surface constituted by a free-form surface based on a plurality of minute reflection surfaces,
Each of the plurality of micro-reflecting surfaces is emitted from a predetermined location in the predetermined light distribution pattern, when a light beam parallel to a horizontal plane including the optical axis of the convex lens is incident on the inside of the lens from the output surface, A vehicular optical unit comprising a reflecting surface formed to reflect the incident light toward the vicinity of the LED light source. The shutter includes a linear ridge line extending in the horizontal direction to form a cut-off line of the predetermined light distribution pattern,
The vehicular optical unit according to claim 4, wherein a distance between the shutter and the incident surface is set within 1 mm.   6. The vehicular optical unit according to claim 4, wherein the shutter is a shutter formed by a paint surface or a vapor deposition surface formed on the incident surface.   A vehicular lamp comprising the vehicular optical unit according to claim 4.

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