Lamp units, vehicle lighting fixtures

Abstract

To provide a lamp unit which can form an irradiation pattern in the vicinity of a vehicle on which the lamp unit is mounted while suppressing an increase in inclination in a condition of being mounted on the vehicle.SOLUTION: A lamp unit 20 comprises: a plurality of light sources (34, 35); a condenser lens 23 for condensing light from the plurality of light sources (34, 35); a light shielding member (24) having a plurality of slit parts 46 that allow the light condensed by the condenser lens 23 to partially pass therethrough; and a projection lens 25 which forms an irradiation pattern Pi having a plurality of irradiation figures Di corresponding to the plurality of slit parts 46 by projecting the light which has passed through the light shield member (24). The plurality of light sources (34, 35) are provided above a projection lens optical axis AI of the projection lens 25, and the plurality of slit parts 46 are provided above the projection lens optical axis AI.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present disclosure relates to a lamp unit and a vehicle lamp.

Background Art

[0002] A vehicle lamp is considered to form an irradiation pattern on the road surface around the vehicle using a lamp unit (see, for example, Patent Document 1). This conventional lamp unit forms an irradiation pattern by projecting light from a light source through a slit of a shade (light shielding member), and can inform a viewer of some intention. This conventional lamp unit is configured to form an irradiation pattern on the road surface by tilting downward.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in such a lamp unit, it is required to form an irradiation pattern in the vicinity of the mounted vehicle, and by increasing the downward tilt of the lamp unit, the position where the irradiation pattern is formed can be brought closer to the vehicle. However, the lamp unit may be provided in the same lamp chamber as other lamps, for example, to constitute a vehicle lamp, but if it is tilted largely, there is a risk of interference with other lamps, and in order to avoid such interference, it is necessary to enlarge the lamp chamber.

[0005] The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a lamp unit capable of forming an irradiation pattern in the vicinity of a mounted vehicle while suppressing an increase in tilt in a state of being mounted on a vehicle, and a vehicle lamp using the same. [Means for solving the problem]

[0006] The vehicle lighting device of this disclosure comprises a plurality of light sources, a focusing lens for focusing light from the plurality of light sources, a light-shielding member provided with a plurality of slits for partially passing through the light focused by the focusing lens, and a projection lens that projects the light passed through the light-shielding member to form an illumination pattern having a plurality of illumination patterns corresponding to the plurality of slits, wherein the plurality of light sources are provided above the projection lens optical axis of the projection lens, and the plurality of slits are provided above the projection lens optical axis. [Effects of the Invention]

[0007] According to the vehicle lighting device of this disclosure, it is possible to form an illumination pattern near the vehicle on which it is mounted while suppressing an increase in tilt when mounted on a vehicle. [Brief explanation of the drawing]

[0008] [Figure 1] This is an explanatory diagram showing how the vehicle lighting fixture of Embodiment 1 according to this disclosure is mounted on a vehicle and forms its respective illumination pattern. [Figure 2] This is an explanatory diagram showing the configuration of a lamp unit in a vehicle lighting system. [Figure 3] This is an explanatory diagram showing the disassembled components of a lamp unit. [Figure 4] This is an explanatory diagram showing a cross-section obtained along line II as shown in Figure 2. [Figure 5] This is an explanatory diagram showing the positional relationship between the first and second light sources in the light source section. [Figure 6] This is an explanatory diagram showing the configuration and positional relationship of the first slit section, the second slit section, and the third slit section in the shade. [Figure 7] This is an explanatory diagram showing the condensing lens as viewed from the light source side. [Figure 8] This is an explanatory diagram showing the condensing lens as viewed from the shade side. [Figure 9]This is an explanatory diagram illustrating how, in a lamp unit, light from a first light source enters the first lens portion from an inclined incidence surface on a cross-sectional (horizontal) plane, is reflected by a reflective surface, and then travels through the shade (its first and second slit portions) to the projection lens. [Figure 10] This is an explanatory diagram showing the luminous flux distribution in the first illumination region formed on the shade by light from a first light source that enters the first lens portion from an inclined incident surface, is reflected by a reflective surface, and then exits from the first outer exit surface. [Figure 11] This is an explanatory diagram showing how, in a lamp unit, light from a first light source enters the first lens portion from the opposing incident surface, then proceeds through the shade (its first and second slit portions) to the projection lens in a cross-sectional view (horizontal cross-section). [Figure 12] This is an explanatory diagram showing the luminous flux distribution in the second irradiation region formed on the shade by light from a first light source that enters the first lens portion from the opposing incident surface and exits from the first inner exit surface. [Figure 13] This is an explanatory diagram showing how, in a lamp unit, light from a second light source enters the second lens portion from the second incident surface, then proceeds through the shade (its third slit portion) to the projection lens in a cross-sectional view (horizontal cross-section). [Figure 14] This is an explanatory diagram showing the light beam distribution in the third irradiation region formed on the shade by light from the second light source that enters the second lens portion from the second incident surface and exits from the second exit surface. [Modes for carrying out the invention]

[0009] Below, an example of a vehicle lighting device according to this disclosure, specifically an embodiment 1 of the lamp unit 20 and vehicle lighting device 10, will be described with reference to the drawings. In Figure 1, the vehicle lighting device 10 is emphasized relative to the vehicle 1 to facilitate understanding of how the vehicle lighting device 10 is installed, and does not necessarily correspond to the actual appearance. Also, in Figure 4, the individual slits 46 of the shade 24 are omitted. Furthermore, in Figures 9, 11, and 13, the shade 24 is schematically shown to facilitate understanding of how light propagates, and the opposing incident surface 53, inclined incident surface 54, reflective surface 55, inner exit surface 57, outer exit surface 58 of the first lens portion 51 of the condensing lens 23, which have a significant optical influence, and the second incident surface 61 and second exit surface 62 of the second lens portion 52, as well as the incident surface and exit surface of the projection lens 25, are emphasized. In Figures 10, 12, and 14, the light distribution (luminous flux) is shown by dividing the region according to the height of the luminous flux (light intensity) with lines, and the luminous flux increases towards the center of the region, similar to contour lines. [Examples]

[0010] A vehicle lighting device 10 of Embodiment 1, an embodiment of the vehicle lighting device according to this disclosure, will be described with reference to Figures 1 to 14. As shown in Figure 1, the vehicle lighting device 10 of Embodiment 1 is used as a lighting device for a vehicle 1 such as an automobile, and is separate from signal lights such as backup lamps (stop lamps) and turn lamps provided on the vehicle 1, and forms an illumination pattern Pi on the road surface 2 surrounding the rear of the vehicle 1, and is provided at the rear of the vehicle 1. The area surrounding the rear of the vehicle 1 is defined by the distance from the vehicle 1 by law, etc., and is, for example, an area within 3m from the vehicle 1.

[0011] In the first embodiment, the vehicle lamp 10 forms signal lamps such as a back lamp and a turn lamp provided on the vehicle 1. In the first embodiment, it is a back lamp and is provided in pairs on the left and right at the rear side of the vehicle 1. Note that the vehicle lamp 10 may form other signal lamps, for example, a clearance lamp, a turn lamp, a tail lamp, etc., and is not limited to the first embodiment. The two vehicle lamps 10 have basically the same configuration except that the positions where they are attached and the positions where the irradiation pattern Pi is formed are different. Therefore, hereinafter, it will be simply described as the vehicle lamp 10.

[0012] The vehicle lamp 10 is configured such that a signal lamp unit and a lamp unit 20 are provided in a lamp chamber formed by covering the open end of the lamp housing with a lamp lens. In the first embodiment, this vehicle lamp 10 is disposed at a position higher than the road surface 2 at the front end of the vehicle 1, and the lamp unit 20 (see FIG. 2 etc.) is provided in a state where the projection optical axis Lp is inclined with respect to the road surface 2. In the following description, in the lamp unit 20, the direction in which the projection optical axis Lp, which is the direction in which light is irradiated (projected), extends is defined as the optical axis direction (denoted as Z in the drawings), the vertical direction when the optical axis direction is along the horizontal plane is defined as the up-down direction (denoted as Y in the drawings), and the direction orthogonal to the optical axis direction and the up-down direction (horizontal direction) is defined as the width direction (denoted as X in the drawings) (see FIG. 2 etc.).

[0013] As shown in FIGS. 2 and 3, the lamp unit 20 has a light source unit 22, a condenser lens 23, a shade 24, and a projection lens 25 attached to an installation base portion 21, and is a single projection optical system, constituting a projector-type road surface projection unit. The installation base portion 21 is a location where the light source unit 22 is provided, is formed of aluminum die-cast or resin having heat conductivity, and functions as a heat sink that releases the heat generated by the light source unit 22 to the outside as a whole. The installation base portion 21 has a base portion 31 and a pair of attachment arm portions 32.

[0014] The base portion 31 is in the shape of a flat plate orthogonal to the optical axis direction, and the light source unit 22 is attached to the central light source attachment location. This light source attachment location has a flat surface, and is provided with two screw holes 31a and two positioning protrusions 31b. Further, in the base portion 31, a plurality of heat radiation fins 31c are provided, and the heat generated by the light source unit 22 installed at the light source attachment location is mainly radiated to the outside from each heat radiation fin 31c.

[0015] A pair of attachment arm portions 32 are provided in pairs on both outer sides in the width direction of the light source unit 22, and protrude forward in the optical axis direction from the base portion 31. Both ends of the attachment arm portions 32 in the forward side in the optical axis direction are in a plane orthogonal to the optical axis direction. Each end is provided with a positioning protrusion 32a and a screw hole 32b. The positioning protrusion 32a is provided at the lower part in the vertical direction at the end of each attachment arm portion 32, and protrudes forward in the optical axis direction. The screw hole 32b is provided at the upper part in the vertical direction at the end, and enables fixing of the condenser lens 23, the shade 24, and the projection lens 25 by screwing in the screw 33.

[0016] The light source unit 22 includes a first light source 34, a second light source 35, and a substrate 36 on which they are mounted. These two light sources (34, 35) are composed of light emitting elements such as LEDs (Light Emitting Diodes). In the first embodiment, the two light sources (34, 35) emit white light (white light) in a Lambertian distribution centered on the emission optical axis. Note that the color (wavelength band), the mode of distribution, the number of colors, etc. of the two light sources (34, 35) may be set as appropriate and are not limited to the configuration of the first embodiment. As shown in FIG. 5 and the like, the two light sources (34, 35) in the first embodiment are positioned above the projection optical axis Lp and arranged side by side in the vertical direction, with the first light source 34 positioned on the projection optical axis Lp side and the second light source 35 positioned above the first light source 34. Both light sources (34, 35) in the first embodiment are substantially square in shape.

[0017] The substrate 36 is a plate-shaped substrate made of a resin material such as a glass epoxy substrate, and each light source (34, 35) is mounted on it. The substrate 36 has two screw holes 36a corresponding to each screw hole 31a at the light source mounting location on the base portion 31 of the mounting stand portion 21, and two positioning holes 36b corresponding to each positioning projection 31b at the light source mounting location. The substrate 36 is attached to the base portion 31 by passing the positioning projection 31b corresponding to each positioning hole 36b through the screws 37 that are passed through each screw hole 36a and screwed into the corresponding screw holes 31a. In this way, the substrate 36 positions each mounted light source (34, 35) facing the condensing lens 23. The substrate 36 is provided with connector terminals electrically connected to the wiring pattern, and power is supplied from the lighting control circuit as needed via these connector terminals to light each light source (34, 35) as needed.

[0018] The condensing lens 23 focuses the light emitted from each light source (34, 35), concentrating the light around each slit portion 46 on the shade 24, that is, in the region on the shade 24 where the three slit portions 46 are provided. The condensing lens 23 has a condensing lens body 41 that focuses the light from each light source (34, 35), and a pair of condensing lens mounting pieces 42 that extend from there in the width direction. The condensing lens body 41 and the condensing lens mounting pieces 42 are formed as a single unit, and in Embodiment 1, they are formed as a single unit by resin molding using a mold. The optical properties of the condensing lens body 41 are set to form a predetermined light distribution area on the shade 24. This will be described later.

[0019] Both condensing lens mounting pieces 42 are plate-shaped and perpendicular to the optical axis direction, and can be fitted onto the ends of both mounting arms 32 of the base portion 31 of the mounting stand 21. Each condensing lens mounting piece 42 is provided with a condensing lens positioning hole 42a and a condensing lens screw hole 42b. Each condensing lens positioning hole 42a allows the positioning projection 32a to be fitted into the condensing lens mounting piece 42 when it is fitted onto the ends of both mounting arms 32. Each condensing lens screw hole 42b allows a screw 33 to be passed through the screw hole 32b when the condensing lens mounting piece 42 is fitted onto the ends of both mounting arms 32. The condensing lens 23 is attached to both mounting arms 32 (their ends) of the mounting base 21 by passing a positioning projection 32a corresponding to each condensing lens positioning hole 42a through it, and then screwing each screw 33, which is passed through each condensing lens screw hole 42b, into the corresponding screw hole 32b.

[0020] The shade 24 is an example of a light-shielding member that forms an illumination pattern Pi by partially passing light from each light source (34, 35) focused by the condensing lens 23 through each slit portion 46, which will be described later. As shown in Figure 1, the illumination pattern Pi consists of three illumination patterns Di aligned at approximately equal intervals in the direction away from the vehicle 1. Here, when each illumination pattern Di is shown individually, the one furthest from the vehicle 1 is called the first illumination pattern Di1, and as it approaches the vehicle 1, they are sequentially called the second illumination pattern Di2, the third illumination pattern Di3, and so on. In Embodiment 1, each illumination pattern Di is approximately a rectangle with the vehicle 1 side as the shorter side, and is approximately the same size and shape as the others, and is arranged at approximately equal intervals.

[0021] This illumination pattern Pi is formed on the road surface 2, which serves as the projection surface, with the first illumination pattern Di1, the second illumination pattern Di2, and the third illumination pattern Di3 arranged on the same straight line so as to move away from the vehicle 1. Therefore, the illumination pattern Pi can be perceived as a line of light extending in the direction in which the three illumination patterns Di are arranged. This illumination pattern Pi, consisting of the three illumination patterns Di, is formed by the shade 24.

[0022] As shown in Figures 3 and 6, the shade 24 is basically formed of a plate-shaped member that obstructs the transmission of light, and has a shade portion 43 and a pair of shade mounting pieces 44. The shade mounting pieces 44 extend from the shade portion 43 on both sides in the width direction and can be fitted onto each of the condensing lens mounting pieces 42 of the condensing lens 23 attached to the ends of both mounting arms 32 of the mounting base portion 21. Each shade mounting piece 44 is provided with a shade positioning hole 44a and a shade screw hole 44b. Each shade positioning hole 44a allows a positioning projection 32a to be fitted into it when the shade mounting piece 44 is fitted onto the condensing lens mounting piece 42. Each shade screw hole 44b allows a screw 33 to be passed through the condensing lens screw hole 42b when the shade mounting piece 44 is fitted onto the condensing lens mounting piece 42. The shade 24 is attached to the mounting arms 32 of the mounting base 21 via the focusing lens 23 by passing a positioning projection 32a corresponding to each shade positioning hole 44a through it, and then screwing each screw 33, which is passed through each shade screw hole 44b, into the corresponding screw hole 32b. With the shade mounting piece 44 attached to the mounting arms 32, the center of the shade 43 is positioned on the projection optical axis Lp.

[0023] The shade portion 43 is provided with multiple slit portions 46 formed by partially cutting out and penetrating a plate-shaped member. Each slit portion 46 partially passes through the light from each light source (34, 35) focused by the condensing lens 23 (its condensing lens body 41), thereby shaping the projected illumination pattern Pi into a predetermined shape. In Embodiment 1, the slit portions 46 correspond to the illumination pattern Pi, and three slit portions are provided in Embodiment 1.

[0024] These three slit sections 46 correspond one-to-one with the three illumination patterns Di. Since the projection lens 25 projects the inverted aperture shape of each slit section 46 provided in the shade 24 onto the road surface 2, the slit sections 46 are rotationally symmetrical with respect to the positional relationship of each illumination pattern Di in the illumination pattern Pi, with respect to the projection optical axis Lp. For this reason, the lowest first slit section 461 in the vertical direction corresponds to the first illumination pattern Di1 of the illumination pattern Pi, the second slit section 462 above it corresponds to the second illumination pattern Di2, and the third slit section 463 above it corresponds to the third illumination pattern Di3.

[0025] Each slit portion 46 is positioned and sized on the shade portion 43 so that each projected pattern Di on the road surface 2 is of the desired size and in the desired positional relationship. In the shade 24 of Embodiment 1, as shown in Figure 6, three slit portions 46 are positioned above the projection optical axis Lp and arranged in a vertical direction, with the first slit portion 461 located closest to the projection optical axis Lp, the second slit portion 462 located above the first slit portion 461, and the third slit portion 463 located above the second slit portion 462. The first slit portion 461 and the second slit portion 462 correspond to the first light source 34, and the third slit portion 463 corresponds to the second light source 35. In the vertical direction, the center position C1 of the first slit portion 461 and the second slit portion 462 is located below the center position C2 of the first light source 34. The center position C1 of the first slit portion 461 and the second slit portion 462 is the vertical center of the region in which they are provided, and in Embodiment 1, it is near the lower end of the second slit portion 462. In addition, the center position C3 of the third slit portion 463 is located below the center position C4 of the second light source 35 in the vertical direction. Therefore, each slit portion 46 is located below the corresponding light source (34, 35) when viewed from its respective center position (C1 to C4). The light transmitted through this shade 24 (each slit portion 46) is projected onto the road surface 2 by the projection lens 25.

[0026] Each of the slit sections 46 is approximately trapezoidal in shape. The size, shape, and spacing of the three slit sections 46 are set according to the distance to the road surface 2, so that each projected pattern Di on the road surface 2 forms a rectangle of approximately equal spacing with the size shown in Figure 1 above. In other words, since the optical distance from each slit section 46 to the road surface 2 via the projection lens 25 is different, when projected onto the road surface 2 by the projection lens 25, each slit section 46 (each projected pattern Di, which is the light transmitted through it) is set to a size and spacing according to that distance. In Embodiment 1, the first slit section 461 is the smallest approximately trapezoid, the second slit section 462 is a larger approximately trapezoid than the first slit section 461, and the third slit section 463 is a larger approximately trapezoid than the second slit section 462. Furthermore, each slit portion 46 is wider in the width direction than the corresponding illumination pattern Di, and the distance between the second slit portion 462 and the third slit portion 463 is greater than the distance between the first slit portion 461 and the second slit portion 462.

[0027] Thus, the three slit sections 46 are of different sizes and shapes, as well as spaced apart, for each projection pattern Di. In each slit section 46, the first slit section 461 is the smallest, and when the light that passes through it is projected onto the road surface 2, it is magnified at the greatest rate to form the first projection pattern Di1. In addition, in each slit section 46, the third slit section 463 is the largest, and when the light that passes through it is projected onto the road surface 2, it is magnified at the smallest rate to form the third projection pattern Di3.

[0028] As shown in Figures 2 to 4, the projection lens 25 has a projection lens body 47 that projects light passed through the shade 24, and a pair of projection lens mounting pieces 48 extending from there in the width direction. The projection lens body 47 is a circular convex lens when viewed in the direction of the optical axis, and in Embodiment 1, the incident surface and the exit surface are free-form surfaces with convex surfaces. The projection lens body 47 projects each slit portion 46 of the shade 24, thereby forming an illumination pattern Pi on the road surface 2 which is inclined with respect to the projection optical axis Lp (see Figure 1). Note that the incident surface and the exit surface can be convex or concave, as long as the projection lens body 47 is a convex lens, and are not limited to the configuration of Embodiment 1.

[0029] Both projection lens mounting pieces 48 are plate-shaped and perpendicular to the optical axis, and can be fitted onto each shade mounting piece 44 of the shade 24 attached to the ends of both mounting arms 32 of the mounting base 21. Each projection lens mounting piece 48 is provided with a projection lens positioning hole 48a and a projection lens screw hole 48b. Each projection lens positioning hole 48a allows a positioning projection 32a to be fitted into it when the projection lens mounting piece 48 is fitted onto the shade mounting piece 44. Each projection lens screw hole 48b allows a screw 33 to be passed through the shade screw hole 44b when the projection lens mounting piece 48 is fitted onto the shade mounting piece 44. The projection lens 25 is attached to both mounting arms 32 (their ends) of the mounting base 21 by passing positioning protrusions 32a corresponding to each projection lens positioning hole 48a through them, and then screwing each screw 33, which passes through each projection lens screw hole 48b, into the corresponding screw hole 32b. As a result, the projection lens 25 has its projection lens optical axis Al, which is the optical axis of the projection lens body 47, oriented in a predetermined direction. This projection lens optical axis Al defines the projection optical axis Lp of the lamp unit 20.

[0030] Next, the configuration of the condensing lens body 41 of the condensing lens 23 will be explained mainly using Figures 7 to 14. This condensing lens body 41 has a first lens portion 51 corresponding to the first light source 34 and a second lens portion 52 corresponding to the second light source 35. In the condensing lens body 41 of Embodiment 1, the first lens portion 51 and the second lens portion 52 are integrally formed with the second lens portion 52 mounted on top of the first lens portion 51. In the condensing lens 23 of Embodiment 1, the shape of the first lens portion 51 and the second lens portion 52, i.e., the optical setting, is determined so that the light emitted from the light source portion 22, i.e., each light source (34, 35), will appropriately illuminate each slit portion 46 of the shade 24.

[0031] The first lens section 51 is positioned opposite the first light source 34 in the optical axis direction (located on the emission optical axis of the first light source 34), and collects light from the first light source 34 into the region of the shade 24 where the first slit section 461 and the second slit section 462 are provided. On the lens side surface of the first lens section 51 that faces the first light source 34, as shown in Figures 4, 7, and 8, the central part is recessed inward from the condensing lens 23 (opposite side from the light source section 22), and in the center there is an opposing incident surface 53 that is curved outwardly convex, an inclined incident surface 54 surrounding it, and a reflective surface 55 that surrounds the inclined incident surface 54 in a frustoconical shape.

[0032] The opposing incident surface 53 is positioned opposite the first light source 34 in the optical axis direction and on its output optical axis, with the first light source 34 located near the rear focal point. The opposing incident surface 53 causes the light emitted from the first light source 34 to enter the first lens section 51 as parallel light traveling approximately parallel to the axis of the first lens section 51, and directs it toward the inner output surface section 57, which will be described later (see Figure 11). This parallel light refers to light that has been collimated after passing through the opposing incident surface 53.

[0033] The inclined incident surface 54 is provided projecting toward the first light source 34, and directs light from the first light source 34 that does not proceed toward the opposing incident surface 53 into the first lens section 51. The reflective surface 55 is provided at a position where light incident from the inclined incident surface 54 into the condensing lens 23 proceeds (see Figure 9). The reflective surface 55 reflects the light incident from the inclined incident surface 54 and directs it toward the outer exit surface section 58, which will be described later, as parallel light that proceeds approximately parallel to the axis of the first lens section 51 (see Figure 9). The reflective surface 55 may reflect light using total internal reflection, or it may reflect light by bonding aluminum, silver, etc., to it by vapor deposition or painting.

[0034] In this first lens section 51, a first emission surface 56 is provided opposite the region of the shade 24 where the first slit section 461 and the second slit section 462 are located, and the light from the first light source 34 is focused into the region of the shade 24 where the first slit section 461 and the second slit section 462 are located. In the first lens section 51, light that has passed through the opposing incident surface 53 becomes direct light that goes directly toward the first emission surface 56, and light that has passed through the inclined incident surface 54 and been reflected by the reflective surface 55 is reflected internally before becoming reflected light that goes toward the first emission surface 56. Because the first lens section 51 is configured in this way, the light emitted from the corresponding first light source 34 can be utilized efficiently.

[0035] As shown in Figure 8, the first emission surface 56 is circular in shape with a portion of the top and bottom cut out when viewed from the front, and has an inner emission surface portion 57 and an outer emission surface portion 58 with different optical settings. The inner emission surface portion 57 is provided in the region on the first emission surface 56 where light that has passed through the opposing incident surface 53 travels (see Figure 11), and is substantially circular in shape when viewed from the front. The inner emission surface portion 57 protrudes outward from the condensing lens 23 (towards the projection lens 25 (front side in the front-rear direction)) than the outer emission surface portion 58. This inner emission surface portion 57 refracts the light that has passed from the first light source 34 through the opposing incident surface 53, thereby appropriately superimposing multiple light distribution images of the first light source 34 on the first slit portion 461 and the second slit portion 462 of the shade 24 at positions according to the optical characteristics. These optical characteristics can be set by adjusting the curvature (surface shape) of the inner exit surface portion 57 along with the opposing incident surface 53 at each location. In Embodiment 1, the curvature is set by gradually changing it.

[0036] The outer emission surface portion 58 is provided so as to surround the region that sandwiches the inner emission surface portion 57 in the width direction and the region below the inner emission surface portion 57, and is located in the region through which light reflected from the reflective surface 55 via the inclined incident surface 54 from the first light source 34 travels (see Figure 9). The outer emission surface portion 58 is located on the inside (rear side in the front-to-back direction) of the condensing lens 23 compared to the inner emission surface portion 57. The outer emission surface portion 58 refracts the light reflected from the reflective surface 55 via the inclined incident surface 54 from the first light source 34, thereby appropriately superimposing multiple light distribution images of the first light source 34 on the first slit portion 461 and the second slit portion 462 of the shade 24 at positions corresponding to the optical characteristics. These optical characteristics can be set by adjusting the curvature (surface shape) of the outer emission surface portion 58 together with the reflective surface 55 at each location, and in Embodiment 1, these curvatures are set by gradually changing them.

[0037] Here, in the first lens section 51, the outer emission surface section 58 is set, as shown in Figure 9, to concentrate the light reflected from the first light source 34 via the inclined incidence surface 54 and the reflective surface 55 at a first position P1 slightly beyond the shade 24, at least in the cross-section (horizontal cross-section). This first position P1 is set from the viewpoint of preventing light from propagating to the peripheral edge of the projection lens 25 (its projection lens body 47). Furthermore, the first position P1 is set near the shade 24 so that the light from the outer emission surface section 58, which is larger than the first slit section 461 and the second slit section 462, can be concentrated on the first slit section 461 and the second slit section 462. This first lens section 51 forms the first illumination region A1 shown in Figure 10 by irradiating the shade 24 with the light reflected from the reflective surface 55 via the inclined incidence surface 54 from the first light source 34 through the outer emission surface section 58. This first irradiation area A1 irradiates the entire area of ​​the first slit portion 461 and the second slit portion 462 to increase the light flux density, with the light flux density being particularly high in the approximately upper half of the first slit portion 461 and the approximately lower half of the second slit portion 462.

[0038] Furthermore, in the first lens section 51, the inner emission surface section 57 is set, as shown in Figure 11, to concentrate light from the first light source 34 through the opposing incident surface 53 at a second position P2 beyond the shade 24, at least in the cross-section (horizontal cross-section). This second position P2 is set from the viewpoint of preventing light from propagating to the peripheral edge of the projection lens 25 (its projection lens body 47). Also, the second position P2 is located further from the shade 24 than the first position P1, that is, it is located further towards the projection lens 25 than the first position P1. This second position P2 is set between the shade 24 and the projection lens 25 so that light from the inner emission surface section 57, which is located inside the outer emission surface section 58, can be collected at the first slit section 461 and the second slit section 462. The first lens portion 51 forms the second illumination region A2 shown in Figure 12 by irradiating the shade 24 with light that has passed from the first light source 34 through the opposing incident surface 53 from the inner exit surface portion 57. This second illumination region A2 irradiates the entire first slit portion 461 to achieve the highest light flux density, and also irradiates the entire second slit portion 462.

[0039] Therefore, the first lens portion 51 is formed on the shade 24 by overlapping the first illumination area A1 and the second illumination area A2 with light from the first light source 34. As a result, the first lens portion 51 has the highest luminous flux density in the first slit portion 461 and the next highest luminous flux density in the second slit portion 462, allowing the entire area of ​​the first slit portion 461 and the second slit portion 462 to be illuminated. Note that the first lens portion 51 is not limited to Embodiment 1, as long as it forms a light distribution area that brightens the first slit portion 461 and the second slit portion 462 from the viewpoint of appropriately forming the corresponding first illumination pattern Di1 and second illumination pattern Di2. The brightness distribution and shape of the light distribution area formed by the inner emission surface portion 57 and the outer emission surface portion 58 can be set as appropriate.

[0040] As shown in Figures 4, 7, and 8, the second lens portion 52 is a convex lens that is elongated in the width direction when viewed from the front in the optical axis direction, and as a whole, it focuses the broad light emitted from the second light source 35 into the region where the third slit portion 463 of the shade 24 is provided (see Figure 13). This second lens portion 52 has a second incident surface 61 facing the second light source 35 and a second exit surface 62 facing the opposite side. In Embodiment 1, the second lens portion 52 is a free-form surface with the second incident surface 61 and the second exit surface 62 being convex. Note that the second incident surface 61 and the second exit surface 62 can be convex or concave, as long as the second lens portion 52 is a convex lens, and are not limited to the configuration of Embodiment 1.

[0041] The second incident surface 61 faces the second light source 35 in the optical axis direction, and the second light source 35 is positioned near the rear focal point. The second incident surface 61 causes the light emitted from the second light source 35 to enter the second lens section 52 as parallel light traveling approximately parallel to the axis of the second lens section 52 (see Figure 13). The second exit surface 62 is provided on the opposite side of the second incident surface 61 and refracts the light that has passed through the second incident surface 61, causing it to travel forward in the front-to-back direction while being focused. By irradiating the second exit surface 62 with light from the second light source 35 that has passed through the second incident surface 61, the second exit surface 62 appropriately superimposes multiple light distribution images of the second light source 35 on the shade 24 (shade section 43) at positions according to the optical characteristics. These optical characteristics can be set by adjusting the curvature (surface shape) of the second exit surface 62 along with the second incident surface 61 at each location, and in Embodiment 1, the curvature is set by gradually changing it.

[0042] Here, in the second lens section 52, the second emission surface 62 is set, as shown in Figure 13, to concentrate the light from the second light source 35 through the second incident surface 61 at a third position P3 that is far beyond the shade 24, at least in the cross-section (horizontal cross-section). This third position P3 is set from the viewpoint of preventing light from propagating to the peripheral edge of the projection lens 25 (its projection lens body 47). Furthermore, the third position P3 is set to be further from the shade 24 than the second position P2, that is, displaced closer to the projection lens 25 than the second position P2, so as not to excessively concentrate the light from the second emission surface 62 into the third slit section 463, which corresponds to the third illumination pattern Di3, and the third illumination pattern Di3 is formed at the closest position among the illumination patterns Di. The second lens section 52 then irradiates the shade 24 from the second emission surface 62 with light that has passed from the second light source 35 through the second incident surface 61, thereby forming the third irradiation region A3 shown in Figure 14. This third irradiation region A3 irradiates the entire third slit section 463 while increasing the light flux density of the lower half of the third slit section 463. Overall, the light flux of this third irradiation region A3 is lower than that of the irradiation of the first slit section 461 and the second slit section 462 by the first lens section 51.

[0043] The condensing lens 23 illuminates the entire area of ​​the first slit section 461 and the second slit section 462 with light from the first light source 34 using the first lens section 51, and illuminates the entire area of ​​the third slit section 463 with light from the second light source 35 using the second lens section 52. The condensing lens 23 has the highest light flux density in the first slit section 461, followed by the second slit section 462, and then the third slit section 463. As a result, the condensing lens 23 can appropriately illuminate the first slit section 461, the second slit section 462, and the third slit section 463 on the shade 24.

[0044] Next, the operation of the vehicle lighting device 10 will be explained. In the lamp unit 20, the vehicle lighting device 10 can turn on and off the light sources (34, 35) by supplying power from the lighting control circuit to each light source (34, 35) from the circuit board 36. The light from each light source (34, 35) is focused by the focusing lens 23 and illuminates the shade 24, and after passing through each slit portion 46 of the shade, it is projected by the projection lens 25 to form an illumination pattern Pi on the road surface 2. The illumination pattern Pi is formed by the projection of the light that has passed through each slit portion 46 of the shade 24, which has the above-described light distribution (luminous flux) distribution, by the projection lens 25, so that three illumination patterns Di are simultaneously formed in a straight line.

[0045] The vehicle lighting device 10 has a lamp unit 20 that is linked to the reverse lamp. When the reverse lamp is turned on, both left and right light sources (34, 35) are illuminated, forming an illumination pattern Pi on the road surface 2. Therefore, the vehicle lighting device 10 allows the illumination pattern Pi formed on the road surface 2 to be seen even when the vehicle 1 is reversing, for example, by a pedestrian who is looking at their smartphone and is not paying much attention to what is in front of them. In addition, the vehicle lighting device 10 allows the driver of the vehicle 1 to see the illumination pattern Pi as the direction in which they are actually reversing, thus assisting driving.

[0046] In this context, conventional vehicle lighting fixtures described in prior art documents form an illumination pattern on the road surface by tilting a lamp unit, which is a combination of a light source, a light-shielding member, and a projection lens, downwards. In such vehicle lighting fixtures, it is necessary to form the illumination pattern near the vehicle on which it is mounted, so it is conceivable to increase the tilt of the lamp unit accordingly. However, in vehicle lighting fixtures, for example, other lighting fixtures may be installed in the same lamp chamber as the lamp unit, but there are size limitations to the lamp chamber, and there is a risk that a greatly tilted lamp unit may interfere with other lighting fixtures. For this reason, conventional vehicle lighting fixtures have limitations in bringing the position of the illumination pattern formed by the lamp unit closer to the vehicle on which it is mounted.

[0047] In contrast, the vehicle lighting fixture 10 has two light sources (34, 35) in the lamp unit 20 positioned above the projection lens optical axis Al, i.e., the projection optical axis Lp, of the projection lens 25, and each slit portion 46 is positioned above the projection lens optical axis Al (projection optical axis Lp). As a result, the lamp unit 20 can direct the direction of light propagation from each light source (34, 35) toward the projection lens 25 through each slit portion 46 downward with respect to the projection optical axis Lp, and the direction of light propagation projected by the projection lens 25 can be directed downward with respect to the projection optical axis Lp (projection lens optical axis Al). As a result, the lamp unit 20 can help to position the location where the illumination pattern Pi is formed near the vehicle 1 on which it is mounted by adjusting the positional relationship between the light source portion 22 and the shade 24 relative to the projection lens 25. This allows the lamp unit 20 to suppress the downward tilt of the projection optical axis Lp within the lamp chamber, and even with this suppressed tilt, it can form the illumination pattern Pi in an area within 3m of the vehicle 1. Furthermore, the lamp unit 20 can assist in forming an illumination pattern Pi near the vehicle 1 by adjusting the positional relationship between the light source unit 22 and the shade 24 with respect to the projection lens 25, thereby simplifying the optical settings of the focusing lens 23.

[0048] Furthermore, in the lamp unit 20, the center position C1 of the first slit portion 461 and the second slit portion 462 is located below the center position C2 of the first light source 34, and the center position C3 of the third slit portion 463 is located below the center position C4 of the second light source 35. As a result, the lamp unit 20 can direct the direction of light propagation from each light source (34, 35) toward the corresponding slit portion 46 downward with respect to the projection optical axis Lp, further enhancing the downward effect caused by the positional relationship between the light source portion 22 and the shade 24 with respect to the projection lens 25. As a result, the lamp unit 20 can make the optical settings in the condensing lens 23 more natural, suppress the downward tilt of the projection optical axis Lp within the lamp chamber, and more appropriately form the illumination pattern Pi in an area within 3m of the vehicle 1.

[0049] Furthermore, the lamp unit 20 sets, in order from the shade 24 side, a focusing position (first position P1) for light reflected by the reflective surface 55 and emitted from the outer emission surface 58, a focusing position (second position P2) for light emitted from the inner emission surface 57 via the opposing incident surface 53, and a focusing position (third position P3) for light emitted from the second emission surface 62 via the second incident surface 61. Therefore, by adjusting each of the above focusing positions, the lamp unit 20 adjusts the light flux density and distribution at each slit portion 46 on the shade 24, so that the irradiation pattern Pi can be appropriately formed with a simple configuration. In particular, in the lamp unit 20 of Embodiment 1, each of the above focusing positions is set from the viewpoint of preventing light from propagating to the periphery of the projection lens 25 (its projection lens body 47), so that the projection lens 25 can project light with less aberration according to the optical setting, and the irradiation pattern Pi can be appropriately formed. This means that since the lamp unit 20 uses white light for each light source (34, 35), it can suppress the occurrence of color fringing (where multiple colors are arranged in a band-like pattern) in the illumination pattern Pi.

[0050] The lamp unit 20 and vehicle lighting fixture 10 of Example 1 can provide the following effects and benefits. The lamp unit 20 comprises multiple light sources (34, 35), a focusing lens 23 that collects the light from them, a shade 24 provided with multiple slits 46 that partially allow the collected light to pass through, and a projection lens 25 that projects the light that has passed through the slits 46 to form an illumination pattern Pi having multiple illumination patterns Di corresponding to the multiple slits 46. In the lamp unit 20, the multiple light sources (34, 35) are positioned above the projection lens optical axis Al of the projection lens 25, and the multiple slits 46 are also positioned above the projection lens optical axis Al. As a result, the lamp unit 20 can direct the direction of light propagation from each light source (34, 35) toward the projection lens 25 through each slit 46 downward with respect to the projection optical axis Lp, and the direction of light propagation projected by the projection lens 25 downward with respect to the projection optical axis Lp (projection lens optical axis Al). As a result, the lamp unit 20 can form an illumination pattern Pi near the vehicle 1 while suppressing the downward tilting of the projected optical axis Lp, and the optical settings of the focusing lens 23 can be simplified.

[0051] In the lamp unit 20, light sources (34, 35) are provided corresponding to at least one slit portion 46, and these light sources (34, 35) are positioned above the central positions (C1, C3) of the corresponding at least one slit portion 46. As a result, the lamp unit 20 can direct the direction of light propagation from each light source (34, 35) toward each corresponding slit portion 46 downward with respect to the projection optical axis Lp, further enhancing the downward effect caused by the positional relationship between the light source unit 22 and the shade 24 with respect to the projection lens 25.

[0052] In the lamp unit 20, the illumination pattern Di has a first illumination pattern Di1, a second illumination pattern Di2, and a third illumination pattern Di3, and has multiple slit sections 46, including a first slit section 461 corresponding to the first illumination pattern Di1, a second slit section 462 corresponding to the second illumination pattern Di2, and a third slit section 463 corresponding to the third illumination pattern Di3. The lamp unit 20 also has a light source, a first light source 34 corresponding to the first slit section 461 and the second slit section 462, and a second light source 35 corresponding to the third slit section 463. The lamp unit 20 positions the center position C2 of the first light source 34 above the center position C1 of the region where the first slit section 461 and the second slit section 462 are provided, and positions the center position C4 of the second light source 35 above the center position C3 of the third slit section 463. Therefore, the lamp unit 20 can direct the direction of light propagation from both light sources (34, 35) toward the corresponding slit portions 46 downward with respect to the projection optical axis Lp, and the direction of light propagation projected from the projection lens 25 can be directed downward with respect to the projection optical axis Lp more effectively.

[0053] In the lamp unit 20, the condensing lens 23 has a configuration in which a first lens portion 51 corresponding to the first light source 34 and a second lens portion 52 corresponding to the second light source 35 are superimposed. In the lamp unit 20, the first lens portion 51 has an opposing incident surface 53 facing the first light source 34, an inclined incident surface 54 surrounding the opposing incident surface 53, and a reflective surface 55 surrounding the inclined incident surface 54, while the second lens portion 52 is a convex lens that focuses the light from the corresponding second light source 35. As a result, the lamp unit 20 can efficiently utilize the light from the first light source 34, and can form a predetermined luminous flux distribution in the first slit portion 461 and the second slit portion 462 while simplifying the configuration of the first lens portion 51. Furthermore, the lamp unit 20 can form a uniform luminous flux distribution in the third slit portion 463 using the light from the second light source 35 with the second lens portion 52. Based on these findings, the lamp unit 20 can form various light beam distributions for each slit portion 46 even when using a single focusing lens 23, thereby forming a more appropriate irradiation pattern Pi.

[0054] In the lamp unit 20, the first lens section 51 sets the focusing position (second position P2) of light that has passed through the opposing incident surface 53 to the projection lens 25 side of the shade 24, and also sets the focusing position (first position P1) of light reflected by the reflective surface 55 to the projection lens 25 side of the shade 24. Furthermore, in the lamp unit 20, the second lens section 52 sets the focusing position (third position P3) of light from the second light source 35 to the projection lens 25 side of the shade 24. As a result, the lamp unit 20 can form a predetermined luminous flux distribution over the entire area of ​​the corresponding slit section 46 on the shade 24 without excessively concentrating light, and can appropriately form the irradiation pattern Pi.

[0055] In the lamp unit 20, the first lens section 51 is set so that the light focusing position (second position P2) of light that has passed through the opposing incident surface 53 is closer to the shade 24 than the light focusing position (third position P3) of light from the second light source 35 in the second lens section 52, and the light focusing position (first position P1) of light reflected by the reflective surface 55 is set closer to the shade 24 than the light focusing position (second position P2) of light that has passed through the opposing incident surface 53. Therefore, by adjusting each of the above-mentioned focusing positions, the lamp unit 20 can adjust the light flux density and distribution at each slit section 46 on the shade 24, and can also be set so that light does not propagate to the periphery of the projection lens 25, thereby appropriately forming the irradiation pattern Pi with a simple configuration.

[0056] The vehicle lighting fixture 10 includes the lamp unit 20 described above. Therefore, the vehicle lighting fixture 10 can form an illumination pattern Pi near the vehicle 1 on which it is mounted, even without arranging the lamp unit 20 so that the projected optical axis Lp is tilted significantly downward, and the lamp unit 20 can be provided while preventing an increase in the size of the lighting chamber.

[0057] Therefore, the lamp unit 20 (vehicle light fixture 10) of Embodiment 1, as a lamp unit (vehicle light fixture) according to the present disclosure, can form an illumination pattern Pi in the vicinity of the vehicle 1 on which it is mounted, while suppressing an increase in tilt when mounted on the vehicle 1.

[0058] Although the vehicle lighting device of this disclosure has been described above based on Example 1, the specific configuration is not limited to Example 1, and changes or additions to the design are permitted as long as they do not deviate from the gist of the invention as described in each claim of the patent.

[0059] In Example 1, the three illumination patterns Di are arranged as approximately rectangles with the vehicle 1 side as the shorter side, and the illumination pattern Pi is formed by aligning them at approximately equal intervals in the direction away from the vehicle 1. However, the illumination pattern is not limited to the configuration of Example 1, as long as it is composed of multiple illumination patterns Di formed by a shade (light-shielding member), the symbols used for the illumination patterns Di, their positions, and the number of illumination patterns Di can be set as appropriate.

[0060] Furthermore, in Example 1, each light source (34, 35) emits white light. However, the color of the light emitted from the light source can be set appropriately according to the location and the message to be conveyed, and is not limited to the configuration of Example 1.

[0061] In Example 1, a shade 24 is used as the light-shielding member, which allows light focused by the focusing lens 23 to pass through each slit portion 46. However, the light-shielding member may have other configurations as long as it is provided with multiple slit portions 46 that partially allow light focused by the focusing lens 23 to pass through, and is not limited to the configuration of Example 1. As an example of other configurations, a light-shielding plate (filter) can be made by providing multiple irradiation slits that partially allow light to pass through a plate-shaped film member that obstructs the transmission of light, and allowing light that has passed through the focusing lens 23 to pass through the multiple irradiation slits.

[0062] In Example 1, a lamp unit 20 (vehicle light fixture 10) is provided in a vehicle 1 driven by a driver. However, the vehicle light fixture may also be provided in a vehicle with an autonomous driving function, and is not limited to the configuration of Example 1. In this case, the vehicle light fixture only needs to form an illumination pattern at a timing appropriate to its intended use, that is, at a timing appropriate to some intention regarding the operation of the vehicle 1, and is not limited to the configuration of Example 1.

[0063] In Example 1, the lamp unit 20 is provided inside the lamp chamber of the vehicle lighting fixture 10. However, the lamp unit may be provided at any location on the vehicle as long as it has the above-described characteristics and is mounted on the vehicle, and is not limited to the configuration of Example 1. Furthermore, the vehicle lighting fixture 10 may consist only of the lamp unit 20, and is not limited to the configuration of Example 1.

[0064] In Example 1, the light source unit 22 is provided on a mounting base unit 21 that functions as a heat sink, and a condensing lens 23, a shade 24, and a projection lens 25 are attached to this mounting base unit 21. However, vehicle lighting fixtures can have other configurations as long as they focus light from a light source onto a light-shielding member with a condensing lens and project it with a projection lens to form an illumination pattern, and are not limited to the configuration of Example 1.

[0065] In Example 1, two light sources 34 and 35 are provided. However, if multiple light sources are provided, the number and arrangement can be set as appropriate, and the configuration is not limited to that of Example 1. [Explanation of Symbols]

[0066] 10 Vehicle lighting fixture 20 Lamp unit 23 Focusing lens 24 Shade (as an example of a light-shielding member) 25 Projection lens 34 First light source 35 Second light source 461 First slit section 462 Second slit section 463 Third slit section 51 First lens section 52 Second lens section 53 Opposing incident surface 54 Inclined incident surface 55 Reflecting surface Al Projection lens optical axis Di1 First illumination pattern Di2 Second illumination pattern Di3 Third illumination pattern Pi Illumination pattern

Claims

1. Multiple light sources, A focusing lens that collects light from multiple light sources, A light-shielding member having multiple slits that partially allow light focused by the aforementioned light-gathering lens to pass through, The system includes a projection lens that projects light passed through the light-shielding member to form an illumination pattern having multiple illumination patterns corresponding to multiple slit portions, All of the aforementioned light sources are positioned above the projection lens optical axis of the projection lens. All of the aforementioned slit portions are provided above the optical axis of the projection lens. All of the aforementioned light sources are provided corresponding to at least one of the aforementioned slit portions. A lamp unit characterized in that all of the light sources are positioned above the center position of at least one of the corresponding slit portions.

2. The illumination pattern comprises a first illumination pattern projected at a distant position in the illumination pattern, a second illumination pattern projected at a closer position than the first illumination pattern in the illumination pattern, and a third illumination pattern projected at a closer position than the second illumination pattern in the illumination pattern, The plurality of slit portions include a first slit portion corresponding to the first illumination pattern, a second slit portion corresponding to the second illumination pattern, and a third slit portion corresponding to the third illumination pattern. The lamp unit according to claim 1, characterized in that the light source comprises a first light source corresponding to the first slit portion and the second slit portion, and a second light source corresponding to the third slit portion.

3. The center position of the first light source is located above the center position of the region in which the first slit portion and the second slit portion are provided. The lamp unit according to claim 2, characterized in that the center position of the second light source is located above the center position of the third slit portion.

4. The focusing lens comprises a first lens portion corresponding to the first light source and a second lens portion corresponding to the second light source, which are superimposed on each other. The first lens portion has an opposing incident surface facing the first light source, an inclined incident surface surrounding the opposing incident surface, and a reflective surface surrounding the inclined incident surface. The lamp unit according to claim 3, characterized in that the second lens portion is a convex lens that focuses light from the corresponding second light source.

5. The first lens portion is configured such that the light-collecting position of the light that has passed through the opposing incident surface is set on the projection lens side of the light-shielding member, and the light-collecting position of the light reflected by the reflective surface is set on the projection lens side of the light-shielding member, The lamp unit according to claim 4, characterized in that the second lens portion is set so that the light-collecting position from the second light source is on the projection lens side of the light-shielding member.

6. The lamp unit according to claim 5, characterized in that the first lens portion is set so that the light-collecting position of the light that has passed through the opposing incident surface is closer to the light-shielding member than the light-collecting position of the light from the second light source in the second lens portion, and the light-collecting position of the light reflected by the reflective surface is set so that the light-collecting position of the light that has passed through the opposing incident surface is closer to the light-shielding member than the light-collecting position of the light that has passed through the opposing incident surface.

7. A vehicle lighting device characterized by comprising a lamp unit according to any one of claims 1 to 6.

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