Vehicle lighting devices and vehicle lamps

Abstract

The objective is to provide a vehicle lighting device and a vehicle lamp that can obtain light distribution characteristics having an asymmetrical luminous intensity distribution in the horizontal and vertical directions. [Solution] The vehicle lighting device according to the embodiment comprises: a socket; a light-emitting module provided on one end side of the socket and having at least one light-emitting element; and an optical element provided on the one end side of the socket and facing the light-emitting element. The optical element has at least one incident surface having a convex curved surface protruding toward the light-emitting element; and an exit surface facing the incident surface and having a plurality of lens portions arranged in a row. The convex curved surface is a paraboloid of revolution or a bipolar surface of revolution. The luminous intensity distribution of the light emitted from the exit surface in a first direction perpendicular to the central axis of the vehicle lighting device is different from the luminous intensity distribution in a second direction perpendicular to the central axis and the first direction.

Description

Technical Field

[0001] Embodiments of the present invention relate to a vehicle lighting device and a vehicle lamp.

Background Art

[0002] From the viewpoints of energy saving and long life, instead of a vehicle lighting device provided with a lamp having a filament, etc., the spread of a vehicle lighting device provided with a light-emitting element such as a light-emitting diode has been progressing. Such a vehicle lighting device includes a socket and a light-emitting module provided on one end side of the socket and having a light-emitting element.

[0003] Here, in the case of a vehicle lighting device, the light distribution characteristics required may differ depending on the use of the vehicle lighting device. For example, in the case of a rear fog lamp, a light distribution characteristic is required in which the light irradiation angle of the luminous intensity distribution of the vehicle lighting device in the horizontal direction is larger than the light irradiation angle of the luminous intensity distribution in the vertical direction (a direction perpendicular to the horizontal direction). Such a light distribution characteristic having an asymmetric luminous intensity distribution in the horizontal direction and the vertical direction can be obtained, for example, by changing the arrangement or number of light-emitting elements provided in the light-emitting module. For example, by changing the distance between the optical axis of the vehicle lighting device and the center of the light-emitting element in the horizontal direction and the vertical direction, or by changing the number of light-emitting elements, a light distribution characteristic having an asymmetric luminous intensity distribution in the horizontal direction and the vertical direction can be obtained.

[0004] However, if this is done, for example, it is necessary to change the arrangement and number of a plurality of light-emitting elements for each use of the vehicle lighting device. Therefore, the inventory management of the vehicle lighting device becomes complicated, and the manufacturing cost of the vehicle lighting device increases.

[0005] Therefore, the development of a technology capable of obtaining a light distribution characteristic having an asymmetric luminous intensity distribution in the horizontal direction and the vertical direction has been desired.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2011-171277 [Overview of the project] [Problems that the invention aims to solve]

[0007] The problem that the present invention aims to solve is to provide a vehicle lighting device and a vehicle lamp that can obtain light distribution characteristics having an asymmetrical luminous intensity distribution in the horizontal and vertical directions. [Means for solving the problem]

[0008] The vehicle lighting device according to the embodiment comprises: a socket; a light-emitting module provided on one end of the socket and having at least one light-emitting element; and an optical element provided on the one end of the socket and facing the light-emitting element. The optical element has at least one incident surface having a convex curved surface projecting toward the light-emitting element; and an exit surface facing the incident surface and having a plurality of lens portions arranged in a row. The convex curved surface is a paraboloid of revolution or a bipolar surface of revolution. The luminous intensity distribution of the light emitted from the exit surface in a first direction perpendicular to the central axis of the vehicle lighting device is different from the luminous intensity distribution in a second direction perpendicular to the central axis and the first direction. [Effects of the Invention]

[0009] According to embodiments of the present invention, it is possible to provide a vehicle lighting device and a vehicle lamp that can obtain light distribution characteristics having an asymmetrical luminous intensity distribution in the horizontal and vertical directions. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic exploded view illustrating a vehicle lighting device according to this embodiment. [Figure 2] This is a schematic plan view of the optics department. [Figure 3]This is a schematic side view of the optical section as seen from the vertical direction. [Figure 4] This is a schematic side view of the optical section as seen from the horizontal. [Figure 5] Figure 2 is a schematic cross-sectional view of the optical section in the direction of the AA line. [Figure 6] This diagram illustrates an example of the light distribution characteristics of an optical element. [Figure 7] This is a schematic perspective view illustrating the incident surface. [Figure 8] (a) to (c) are schematic diagrams illustrating the lens portion provided on the emission surface. [Figure 9] (a) and (b) are schematic diagrams illustrating the relationship between the shape of the incident surface and the form of light propagating within the optical element. [Figure 10] This is a schematic partial cross-sectional view illustrating a vehicle lighting fixture. [Modes for carrying out the invention]

[0011] The embodiments will be illustrated below with reference to the drawings. In each drawing, similar components are denoted by the same reference numerals, and detailed descriptions will be omitted as appropriate.

[0012] (Vehicle lighting equipment) The vehicle lighting device 1 according to this embodiment can be installed in, for example, automobiles or railway vehicles. The vehicle lighting device 1 can be used in lamps that require a light distribution characteristic having different light irradiation angles in the horizontal and vertical directions (directions perpendicular to the horizontal direction) (asymmetrical light distribution), such as rear fog lamps. However, the use of the vehicle lighting device 1 is not limited to rear fog lamps.

[0013] Figure 1 is a schematic exploded view illustrating a vehicle lighting device 1 according to this embodiment. As shown in Figure 1, the vehicle lighting device 1 is provided with, for example, a socket 10, a light-emitting module 20, a power supply unit 30, a heat transfer unit 40, and an optical unit 50.

[0014] The socket 10 has, for example, a mounting portion 11, a bayonet 12, a flange 13, heat radiation fins 14, and a connector holder 15.

[0015] The mounting portion 11 is provided on a surface of the flange 13 opposite to the side where the heat radiation fins 14 are provided. The outer shape of the mounting portion 11 is, for example, cylindrical. The mounting portion 11 has, for example, a recess 11a that opens at an end opposite to the flange 13 side.

[0016] The bayonet 12 is provided, for example, on a side surface of the mounting portion 11. The bayonet 12 protrudes toward the outside of the vehicle lighting device 1. The bayonet 12 faces the flange 13. A plurality of bayonets 12 can be provided. The bayonet 12 is used when mounting the vehicle lighting device 1 to, for example, a housing 101 of a vehicle lamp 100 described later. The bayonet 12 can be used for a twist lock.

[0017] The flange 13 has, for example, a substantially disk shape. The side surface of the flange 13 is located outside the vehicle lighting device 1 more than the side surface of the bayonet 12.

[0018] The heat radiation fins 14 are provided on the flange 13 opposite to the mounting portion 11 side. At least one heat radiation fin 14 can be provided. For example, as shown in FIG. 1, a plurality of heat radiation fins 14 can be provided on the socket 10. The plurality of heat radiation fins 14 can be arranged side by side in a predetermined direction. The heat radiation fins 14 have, for example, a plate shape or a cylindrical shape.

[0019] The connector holder 15 is provided on the flange 13 opposite to the mounting portion 11 side. The connector holder 15 can be provided side by side with the heat radiation fins 14. The connector holder 15 has a cylindrical shape, and a connector 105 having a seal member 105a inside is inserted therein.

[0020] The socket 10 has the function of holding the light-emitting module 20, the power supply unit 30, and the optical unit 50, and also the function of transferring heat generated in the light-emitting module 20 to the outside. For this reason, it is preferable to form the socket 10 from a material with high thermal conductivity. The socket 10 can be formed from a metal such as an aluminum alloy, for example.

[0021] Furthermore, the socket 10 can also be formed from, for example, a highly thermally conductive resin. A highly thermally conductive resin is, for example, a resin such as PET (Polyethylene terephthalate) or nylon mixed with a filler such as carbon or aluminum oxide. If the socket 10 contains a highly thermally conductive resin, the heat generated in the light-emitting module 20 can be dissipated efficiently. In addition, the weight of the socket 10 can be reduced.

[0022] The light-emitting module 20 is provided on one end of the socket 10. As shown in Figure 1, the light-emitting module 20 includes, for example, a substrate 21, a light-emitting element 22, a frame portion 23, a sealing portion 24, and a circuit element 25.

[0023] The substrate 21 is bonded, for example, on the heat transfer section 40. As will be described later, the heat transfer section 40 may be omitted. If the heat transfer section 40 is omitted, for example, the substrate 21 is bonded to the bottom surface of the recess 11a. The adhesive used to bond the substrate 21 is preferably an adhesive with high thermal conductivity. For example, the adhesive can be an adhesive mixed with a filler using a conductive material or an inorganic material.

[0024] The substrate 21 is plate-shaped. The planar shape of the substrate 21 (shape when viewed from a direction along the central axis 1a of the vehicle lighting device 1) is, for example, approximately rectangular. The substrate 21 can be formed from, for example, inorganic materials such as ceramics (e.g., aluminum oxide or aluminum nitride), or organic materials such as paper phenol or glass epoxy. The substrate 21 may also be a metal core substrate in which the surface of a metal plate is coated with an insulating material. Furthermore, the substrate 21 may have a single-layer structure or a multi-layer structure.

[0025] Furthermore, a wiring pattern 21a is provided on the surface of the substrate 21. Furthermore, a covering portion can be provided to cover the wiring pattern 21a and the film-shaped resistor described later. The covering portion may include, for example, a glass material.

[0026] The light-emitting element 22 is provided on the substrate 21 (on the side of the substrate 21 opposite to the socket 10 side). The light-emitting element 22 is electrically connected to the wiring pattern 21a. At least one light-emitting element 22 can be provided. The light-emitting module 20 illustrated in Figure 1 is provided with four light-emitting elements 22. Multiple light-emitting elements 22 can be connected in series.

[0027] If one light-emitting element 22 is provided, it can be positioned at the central axis 1a of the vehicle lighting device 1. If multiple light-emitting elements 22 are provided, they can be positioned at rotationally symmetrical locations on the circumference of the vehicle lighting device 1 with respect to its central axis 1a.

[0028] By arranging the light-emitting elements 22 in this manner, it is possible to obtain a light distribution characteristic having a symmetrical luminous intensity distribution in which the light irradiation angle of the luminous intensity distribution is approximately the same in the horizontal direction HH (corresponding to an example of a second direction) and the vertical direction VV (corresponding to an example of a first direction). Therefore, the versatility of the light-emitting module 20 can be improved. Improved versatility of the light-emitting module 20 makes inventory management of the light-emitting module 20 easier and reduces the manufacturing cost of the light-emitting module 20.

[0029] In this specification, the horizontal direction HH and the vertical direction VV refer to the directions when the vehicle lighting device 1 is mounted on the housing 101 of the vehicle lamp 100. In this case, the horizontal direction HH and the vertical direction VV may not be perfect horizontal HH and perfect vertical VV, but may also have errors due to manufacturing errors, mounting errors, etc., of the vehicle lighting device 1 and the optical unit 50. That is, the horizontal direction HH may deviate slightly from the perfect horizontal direction HH, and the vertical direction VV may deviate slightly from the perfect vertical direction VV.

[0030] The light-emitting element 22 can be, for example, a light-emitting diode, an organic light-emitting diode, a laser diode, or the like.

[0031] The light-emitting element 22 can be a chip-shaped light-emitting element, a surface-mount type such as a PLCC (Plastic Leaded Chip Carrier), or a leaded light-emitting element such as a bullet-shaped element. The light-emitting element 22 illustrated in Figure 1 is a chip-shaped light-emitting element. In this case, considering the miniaturization of the light-emitting module 20 and, consequently, the vehicle lighting device 1, it is preferable to use a chip-shaped light-emitting element. In the following, as an example, the case in which the light-emitting element 22 is a chip-shaped light-emitting element will be described.

[0032] The chip-shaped light-emitting element 22 can be mounted on the wiring pattern 21a using COB (Chip On Board). The chip-shaped light-emitting element 22 may be an upper electrode type light-emitting element, an upper and lower electrode type light-emitting element, or a flip-chip type light-emitting element.

[0033] The frame portion 23 is provided on the substrate 21. The frame portion 23 is bonded to the substrate 21. The frame portion 23 has a frame shape and surrounds the light-emitting element 22. The frame portion 23 has the function of defining the formation range of the sealing portion 24 and the function of a reflector. The frame portion 23 can be omitted. If the frame portion 23 is omitted, for example, a dome-shaped sealing portion 24 is provided on the substrate 21. The planar contour of the frame portion 23 is, for example, a circle.

[0034] The sealing portion 24 is provided inside the frame portion 23. The sealing portion 24 is provided so as to cover the area enclosed by the frame portion 23. The sealing portion 24 is provided so as to cover the light-emitting element 22. The sealing portion 24 contains a light-transmitting resin. The resin is, for example, a silicone resin. The sealing portion 24 may also contain a phosphor.

[0035] Furthermore, if the light-emitting element 22 is a surface-mount type light-emitting element or a light-emitting element with lead wires such as a bullet-shaped element, the frame portion 23 and the sealing portion 24 can be omitted.

[0036] The circuit element 25 can be a passive or active element used to constitute a light-emitting circuit having a light-emitting element 22. The circuit element 25 is provided on the substrate 21. The circuit element 25 is provided, for example, around the frame portion 23 and is electrically connected to the wiring pattern 21a.

[0037] The circuit elements 25 illustrated in Figure 1 are a protection element 25a, a resistor 25b, and a control element 25c. However, the types of circuit elements 25 are not limited to those exemplified, and can be appropriately changed depending on the configuration of the light-emitting circuit having the light-emitting element 22. For example, in addition to those mentioned above, the circuit elements 25 may also be capacitors, positive characteristic thermistors, negative characteristic thermistors, inductors, surge absorbers, varistors, transistors, integrated circuits, computing elements, etc.

[0038] The protection element 25a is provided, for example, to prevent a reverse voltage from being applied to the light-emitting element 22, and to prevent pulse noise from being applied to the light-emitting element 22 from the reverse direction. The protection element 25a can be, for example, a diode.

[0039] The resistor 25b can be, for example, a surface-mount resistor, a resistor with leads (metal oxide film resistor), or a film-type resistor formed using a screen printing method. The resistor 25b shown in Figure 1 is a film-type resistor. The resistor 25b is provided, for example, to adjust variations in the forward voltage characteristics of the light-emitting element 22.

[0040] The control element 25c is provided, for example, to switch the voltage applied to the light-emitting element 22 or to perform temperature derating. However, the function and application of the control element 25c are not limited to those exemplified. The control element 25c can be, for example, a transistor or an integrated circuit. The control element 25c exemplified in Figure 1 is a surface-mount integrated circuit.

[0041] The power supply unit 30 has, for example, a plurality of power supply terminals 31 and a holding unit 32. The multiple power supply terminals 31 are rod-shaped, with one end protruding from the bottom surface of the recess 11a. One end of each power supply terminal 31 is soldered to a wiring pattern 21a provided on the substrate 21. The other end of each power supply terminal 31 is exposed inside the hole of the connector holder 15. The connector 105 is fitted onto the multiple power supply terminals 31 exposed inside the hole of the connector holder 15. The multiple power supply terminals 31 are formed from a metal such as a copper alloy.

[0042] If the socket 10 is formed using, for example, a highly thermally conductive resin containing a carbon filler or a metal, then the socket 10 will be conductive. Therefore, the retaining portion 32 is provided to insulate the multiple power supply terminals 31 from the conductive socket 10. Note that if the socket 10 is formed using an insulating highly thermally conductive resin (for example, a highly thermally conductive resin containing an aluminum oxide filler), the retaining portion 32 can be omitted. The retaining portion 32 can be, for example, press-fitted into a hole provided in the socket 10 or bonded to the inner wall of the hole.

[0043] The heat transfer section 40 is plate-shaped and is provided between the socket 10 and the light-emitting module 20 (substrate 21). The heat transfer section 40 is made of a material with high thermal conductivity. For example, the heat transfer section 40 is made of a metal such as aluminum, aluminum alloy, copper, or copper alloy. However, if the socket 10 is made of metal or if the heat generated in the light-emitting module 20 is small, the heat transfer section 40 can be omitted.

[0044] As mentioned above, the versatility of the light-emitting module 20 can be improved if it has a light distribution characteristic in which the light irradiation angle of the luminous intensity distribution in the horizontal direction HH and the vertical direction VV is approximately the same (symmetrical luminous intensity distribution). However, depending on the application of the vehicle lighting device 1, a light distribution characteristic in which the light irradiation angle of the luminous intensity distribution in the horizontal direction HH is wider than the light irradiation angle of the luminous intensity distribution in the vertical direction VV (asymmetrical luminous intensity distribution) may be required.

[0045] Therefore, the vehicle lighting device 1 is provided with an optical unit 50 (optical element 52) ​​that converts the light distribution characteristics of the light-emitting module 20, which have a symmetrical light intensity distribution, to light distribution characteristics that have an asymmetrical light intensity distribution. Figure 2 is a schematic plan view of the optical unit 50. Figure 2 is a schematic plan view of the optical unit 50 as seen from a direction along the central axis 1a of the vehicle lighting device 1. Figure 3 is a schematic side view of the optical unit 50 as seen from the vertical direction VV. Figure 4 is a schematic side view of the optical unit 50 as seen from the horizontal direction HH. Figure 5 is a schematic cross-sectional view of the optical unit 50 in the direction of the AA line in Figure 2.

[0046] As shown in Figures 1 and 5, the optical unit 50 is detachably mounted, for example, on the end of the socket 10 on the side where the light-emitting module 20 is provided. For example, the central axis 50a of the optical unit 50 can be aligned with the central axis 1a of the vehicle lighting device 1. Alternatively, for example, the central axis 50a of the optical unit 50 can be aligned with the central axis of the optical element 52, which will be described later. Also, as shown in Figure 5, the optical unit 50 (flange 51a) can be mounted, for example, to close the opening of the recess 11a of the mounting portion 11.

[0047] As shown in Figures 1 to 5, the optical unit 50 includes, for example, a mounting portion 51 and an optical element 52. The optical element 52 can be formed from a material that can transmit light emitted from the light-emitting module 20 (light-emitting element 22). For example, the optical element 52 can be formed from a light-transmitting resin such as polycarbonate or acrylic, or from glass. The material of the mounting portion 51 is not particularly limited as long as it has a certain degree of rigidity. For example, the mounting portion 51 can be made from resin or metal. The material of the mounting portion 51 may be the same as or different from the material of the optical element 52. If the optical element 52 and the mounting portion 51 are made from the same material, they can be integrally molded using, for example, injection molding. If the optical element 52 and the mounting portion 51 are made from different materials, they can be integrally molded using, for example, two-color molding or insert molding.

[0048] The mounting portion 51 includes, for example, a flange 51a, a support portion 51b, and a retaining portion 51c. The flange 51a is, for example, plate-shaped and is provided on the side surface of the optical element 52. The flange 51a extends horizontally in the direction HH and vertically in the direction VV from the side surface of the optical element 52. The flange 51a is provided, for example, near the end of the optical element 52 on the socket 10 (mounting portion 11) side. As shown in Figure 5, the surface 51aa of the flange 51a on the socket 10 (mounting portion 11) side can be an inclined surface. The surface 51aa is inclined in a direction in which the thickness of the flange 51a gradually increases towards the center of the flange 51a.

[0049] Furthermore, as shown in Figure 3, multiple protrusions 51ab can be provided on the surface 51aa. When the optical unit 50 is mounted on the socket 10 (mounting part 11), the multiple protrusions 51ab come into contact with the ends of the socket 10 (mounting part 11). This allows the position of the optical unit 50 in the direction along the central axis 1a of the vehicle lighting device 1 to be stabilized.

[0050] As shown in Figure 4, for example, a pair of support parts 51b can be provided. The pair of support parts 51b can be arranged side by side in the horizontal direction HH, for example. When the optical unit 50 is mounted in the socket 10 (mounting part 11), the pair of support parts 51b are inserted into the recess 11a of the mounting part 11. At this time, the outer surface of the support part 51b comes into contact with the inner wall of the recess 11a. Therefore, displacement of the optical unit 50 in the horizontal direction HH can be suppressed.

[0051] As shown in Figures 3 and 5, the retaining portion 51c can be provided in pairs, for example. The pair of retaining portions 51c can be arranged side by side in the vertical direction VV, for example. The tip of each retaining portion 51c is provided with a claw 51ca that protrudes toward the center of the flange 51a. As shown in Figure 5, when the optical unit 50 is mounted on the socket 10 (mounting portion 11), the socket 10 (mounting portion 11) is inserted between the pair of retaining portions 51c. At this time, the claw 51ca fits into a hole provided on the side surface of the mounting portion 11. Therefore, it is possible to suppress misalignment of the optical unit 50 in the direction along the central axis 1a of the vehicle lighting device 1 and in the vertical direction VV.

[0052] The optical element 52 is provided on one end of the socket 10 and controls the light distribution characteristics of the light emitted from the light-emitting element 22. In this case, the optical element 52 ensures that the light irradiation angle of the luminous intensity distribution of the light emitted from the optical element 52 in the vertical direction VV perpendicular to the central axis 1a of the vehicle lighting device 1 is different from the light irradiation angle of the luminous intensity distribution in the horizontal direction HH perpendicular to the central axis 1a and the vertical direction VV. For example, the optical element 52 converts a light distribution characteristic having a luminous intensity distribution (symmetrical luminous intensity distribution) where the light irradiation angles of the luminous intensity distribution in the horizontal direction HH and the vertical direction VV are approximately the same, to a light distribution characteristic having a luminous intensity distribution (asymmetrical luminous intensity distribution) where the light irradiation angle of the luminous intensity distribution in the horizontal direction HH is wider than the light irradiation angle of the luminous intensity distribution in the vertical direction VV. For example, the optical element 52 converts the light distribution characteristics (symmetrical luminous intensity distribution) of a general-purpose light-emitting module 20 to light distribution characteristics (asymmetrical luminous intensity distribution) suitable for rear fog lamps, etc.

[0053] Figure 6 is a diagram illustrating an example of the light distribution characteristics of the optical element 52. The angular positions of the rhombus-shaped region shown in Figure 6 are light irradiation angles between +10° and -10° in the horizontal direction HH, and between +5° and -5° in the vertical direction VV. The minimum luminous intensity within the rhombus-shaped region is, for example, 75 cd (candela). The minimum luminous intensity on the horizontal direction HH axis is, for example, 150 cd (candela). The minimum luminous intensity on the vertical direction VV axis is, for example, 150 cd (candela). In addition, the luminous intensity in all directions is, for example, less than 300 cd (candela).

[0054] Such a light distribution characteristic, which has different light irradiation angles in the horizontal direction HH and the vertical direction VV (an asymmetrical light distribution), is suitable for applications such as rear fog lamps.

[0055] As shown in Figure 5, the optical element 52 is provided on one end side of the socket 10 and faces the light-emitting element 22. The optical element 52 has, for example, an incident surface 52a, an incident surface 52b, a reflective surface 52c, a reflective surface 52d, an exit surface 52e, an exit surface 52f, and an exit surface 52g. A recess 52h is provided at the end of the optical element 52 on the side facing the light-emitting element 22. The bottom surface of the recess 52h becomes the incident surface 52a, and the side surface of the recess 52h becomes the incident surface 52b.

[0056] The incident surface 52a has a convex curved surface that protrudes toward the light-emitting element 22. The incident surface 52a faces one of the light-emitting elements 22. Therefore, at least one incident surface 52a is provided.

[0057] Figure 7 is a schematic perspective view illustrating the incident surface 52a. As shown in Figures 5 and 7, multiple incident surfaces 52a are provided in a region that includes the central axis of the optical element 52 (the central axis 50a of the optical unit 50). An incident surface 52a is provided for each light-emitting element 22. That is, the number of incident surfaces 52a can be the same as the number of light-emitting elements 22.

[0058] For example, in the case of the optical element 52 illustrated in Figures 5 and 7, an incident surface 52a is provided for each of the four light-emitting elements 22. In this case, one incident surface 52a faces one of the light-emitting elements 22.

[0059] In the direction along the central axis 50a of the optical unit 50, the incident surface 52a is, for example, a convex curved surface that protrudes toward the light-emitting element 22. When viewed from the direction along the central axis 1a of the vehicle lighting device 1, the vertex of the convex curved incident surface 52a can be, for example, made to coincide with the center of the light-emitting surface of the light-emitting element 22.

[0060] As shown in Figure 5, the incident surface 52b is inclined with respect to the central axis 50a of the optical unit 50. In the direction along the central axis 50a of the optical unit 50, the incident surface 52b is inclined in a direction that approaches the central axis 50a as it moves away from the light-emitting element 22. The incident surface 52b can be a curved surface, for example, like the side surface of a frustum of a cone.

[0061] The reflective surface 52c can be the outer surface of the optical element 52 near the end on the side facing the light-emitting element 22. The reflective surface 52c is inclined with respect to the central axis 50a of the optical unit 50. In the direction along the central axis 50a of the optical unit 50, the reflective surface 52c is inclined away from the central axis 50a as it moves away from the light-emitting element 22. That is, the reflective surface 52c is inclined in the opposite direction to the incident surface 52b. The reflective surface 52c can be a curved surface, such as the side of a frustum of a cone.

[0062] The reflective surface 52d can be the outer surface of the optical element 52 near the end opposite to the light-emitting element 22. The reflective surface 52d is inclined with respect to the central axis 50a of the optical unit 50. In the direction along the central axis 50a of the optical unit 50, the reflective surface 52d is inclined away from the central axis 50a as it moves away from the light-emitting element 22. That is, the reflective surface 52c is inclined in the opposite direction to the incident surface 52b. The reflective surface 52d can be a curved surface, such as the side surface of a frustum of a cone.

[0063] As shown in Figure 5, a mounting portion 51 (flange 51a) can be provided between the reflective surface 52c and the reflective surface 52d. Therefore, the reflective surface 52c and the reflective surface 52d can be discontinuous surfaces. Also, the inclination angle of the reflective surface 52d may be the same as or different from the inclination angle of the reflective surface 52c.

[0064] As shown in Figures 1 and 5, a recess 52i is provided at the end of the optical element 52 opposite to the light-emitting element 22, and a recess 52j is provided at the bottom of the recess 52i. The end of the optical element 52 opposite to the light-emitting element 22 is the emission surface 52g. The bottom of the recess 52i is the emission surface 52f. The bottom of the recess 52j is the emission surface 52e.

[0065] The emission surface 52e is located in a region that includes the central axis 50a of the optical unit 50. When viewed from a direction along the central axis 50a of the optical unit 50, the emission surface 52e can be located in a position that overlaps with the incident surface 52a. That is, the emission surface 52e faces the incident surface 52a, and multiple lens units 52k, which will be described later, are arranged side by side thereon.

[0066] When viewed from a direction along the central axis 50a of the optical unit 50, the emission surface 52f can be positioned to overlap with the reflection surface 52c. When viewed from a direction along the central axis 50a of the optical unit 50, the emission surface 52g can be positioned to overlap with the reflection surface 52d.

[0067] As shown in Figures 1 and 2, multiple lens sections 52k are arranged side by side on the light-emitting surfaces (emitting surface 52e, emitting surface 52f, and emitting surface 52g) of the optical element 52. The emitting surfaces 52e, 52f, and 52g can be, for example, lens arrays.

[0068] Figures 8(a) to 8(c) are schematic diagrams illustrating the lens portion 52k provided on the exit surface. Figure 8(a) is a schematic plan view illustrating the lens section 52k as viewed from a direction along the central axis 50a of the optical section 50. Figure 8(b) is a schematic cross-sectional view of the lens portion 52k in the direction of the BB line in Figure 8(a). Figure 8(c) is a schematic cross-sectional view of the lens portion 52k in the CC line direction in Figure 8(a).

[0069] As shown in Figure 8(a), the shape of the lens portion 52k when viewed from a direction along the central axis 50a of the optical portion 50 can be approximately rhombic. For example, one diagonal 52ka of the lens portion 52k can be parallel to the vertical direction VV. For example, the other diagonal 52kb of the lens portion 52k can be parallel to the horizontal direction HH. In this case, diagonal 52ka can be longer than diagonal 52kb.

[0070] If the lengths of the diagonal 52ka and the diagonal 52kb are different, the radius of curvature of the light-emitting surface of the lens portion 52k can be changed in the vertical direction VV and the horizontal direction HH, as shown in Figures 8(b) and (c). For example, the radius of curvature of the light-emitting surface of the lens portion 52k in the vertical direction VV can be made larger than the radius of curvature of the light-emitting surface of the lens portion 52k in the horizontal direction HH. In this way, the light irradiation angle of the luminous intensity distribution of the light emitted in the vertical direction VV becomes narrower than the light irradiation angle of the luminous intensity distribution of the light emitted in the horizontal direction HH. That is, it is possible to obtain a light distribution characteristic with an asymmetrical luminous intensity distribution between the horizontal direction HH and the vertical direction VV.

[0071] The light-emitting surface of the lens portion 52k can be either a convex or concave curved surface. However, as shown in Figures 8(b) and (c), if the light-emitting surface of the lens portion 52k is a convex curved surface, the accumulation of water droplets and dust can be suppressed. Furthermore, a convex curved surface simplifies the optical design.

[0072] The luminous intensity distribution of light emitted from the lens section 52k in the vertical direction VV, and the luminous intensity distribution of light emitted from the lens section 52k in the horizontal direction HH, can be controlled by the length of the diagonal 52ka, the length of the diagonal 52kb, and the radius of curvature of the light emission surface of the lens section 52k.

[0073] The lengths of the diagonal 52ka, the diagonal 52kb, and the radius of curvature of the light-emitting surface of the lens portion 52k can be appropriately set according to the required luminous intensity distribution. For example, these can be set appropriately through experiments or simulations.

[0074] As shown in Figure 5, the light L1 emitted from the light-emitting element 22 and incident on the incident surface 52a is emitted from the exit surface 52e to the outside of the optical unit 50. In this case, the light L1 is emitted near the central axis 1a of the vehicle lighting device 1.

[0075] A portion of the light (light L2) emitted from the light-emitting element 22 and incident on the incident surface 52b is reflected by the reflective surface 52c and exits from the exit surface 52f to the outside of the optical unit 50. In this case, light L2 is mainly emitted to the area outside the region irradiated by light L1.

[0076] A portion of the light (light L3) emitted from the light-emitting element 22 and incident on the incident surface 52b is reflected by the reflective surface 52d and exits the optical unit 50 from the exit surface 52g. In this case, light L3 mainly illuminates the area outside the region illuminated by light L2.

[0077] In other words, the incident surface 52a, incident surface 52b, reflective surface 52c, and reflective surface 52d distribute the light emitted from the light-emitting element 22 toward the exit surface 52e, exit surface 52f, and exit surface 52g. Therefore, for example, by changing the dimensions of the incident surface 52a or the inclination angles of the incident surface 52b, reflective surface 52c, and reflective surface 52d, the luminous intensity distribution of the light incident on the exit surface 52e, exit surface 52f, and exit surface 52g can be adjusted.

[0078] Furthermore, while the above examples illustrate the control of the luminous intensity distribution of light emitted in the vertical direction VV and the luminous intensity distribution of light emitted in the horizontal direction HH using a roughly rhombic lens portion 52k, as shown in Figure 2, the light emission surface of the optical element 52 can also be further provided with multiple lens portions 52k1 that have a different shape from the lens portion 52k. For example, the shape of the lens portion 52k1 when viewed from a direction along the central axis 50a of the optical unit 50 can be roughly square or roughly rectangular. In this case, for example, one side of the lens portion 52k1 can be parallel to the vertical direction VV. For example, the other side of the lens portion 52k1 can be parallel to the horizontal direction HH.

[0079] Because the difference between the luminous intensity distribution of light emitted in the vertical direction VV and the luminous intensity distribution of light emitted in the horizontal direction HH is small in the lens portion 52k1 having this shape, the control of the luminous intensity distribution by the roughly diamond-shaped lens portion 52k can be adjusted.

[0080] In this case, as shown in Figure 2, multiple lens sections 52k can be arranged in a row in the central region (emission surface 52e, emission surface 52f) of the light emission surface (emission surface 52e, emission surface 52f, emission surface 52g) of the optical element 52.

[0081] In the peripheral region of the light-emitting surface (emitting surface 52g) of the optical element 52, multiple lens sections 52k1 can be arranged in the horizontal HH region, and multiple lens sections 52k can be arranged in the vertical VV region.

[0082] Furthermore, the luminous intensity distribution of light emitted from the lens section 52k1 in the vertical direction VV, and the luminous intensity distribution of light emitted from the lens section 52k1 in the horizontal direction HH, can be controlled by the diagonal dimensions and radius of curvature, similar to the case of the lens section 52k described above.

[0083] Furthermore, in the case of the optical element 52 illustrated in Figure 5, recesses 52i and 52j are provided, but at least one of recesses 52i and 52j can be omitted. For example, the exit surfaces 52e, 52f, and 52g may be continuous in a direction perpendicular to the central axis 50a of the optical unit 50. Alternatively, the incident surface 52a may be provided at the end of the optical element 52 on the side of the light-emitting element 22.

[0084] However, if at least one of the recesses 52i and 52j is provided, the weight of the optical element 52 can be reduced and the material cost can be lowered. Also, as can be seen from Figure 5, if at least one of the recesses 52i and 52j is provided, it is possible to suppress large differences in wall thickness. Therefore, when the optical part 50 is formed by molding methods such as injection molding, two-color molding, and insert molding, it is possible to suppress the occurrence of defects such as sink marks.

[0085] As mentioned above, the light L1 incident on the incident surface 52a is irradiated near the central axis 1a of the vehicle lighting device 1 via the exit surface 52e. Therefore, controlling the luminous intensity distribution by the incident surface 52a and the exit surface 52e is of utmost importance for controlling the light distribution characteristics of the vehicle lighting device 1.

[0086] In this case, as described above, the light L1 incident on the incident surface 52a is irradiated near the central axis 1a of the vehicle lighting device 1 via the exit surface 52e. The light-emitting element 22, such as a light-emitting diode, has the highest intensity of emission in the direction of the optical axis, like Lambertsian light distribution. Therefore, light control near the central axis 1a (optical axis) by the incident surface 52a and the exit surface 52e is of utmost importance for controlling the light distribution characteristics of the vehicle lighting device 1.

[0087] As described above, the emission surface 52e is provided with multiple lens sections 52k, and the luminous intensity distribution of the light emitted from the emission surface 52e, and consequently the light distribution characteristics of the vehicle lighting device 1, are controlled by the dimensions of the lens sections 52k and the radius of curvature of the light emission surface of the lens sections 52k.

[0088] In this case, if the light incident on the incident surface 52a and propagating through the inside of the optical element 52 is parallel light, then parallel light can be incident on the exit surface 52e. If the light incident on the exit surface 52e is parallel light, the optical design of the exit surface 52e (for example, the design of the dimensions of the lens portion 52k and the design of the radius of curvature of the light exit surface of the lens portion 52k) becomes easier. Therefore, the convex curved surface of the incident surface 52a is defined as a paraboloid of revolution or a dipole of revolution.

[0089] Figures 9(a) and 9(b) are schematic diagrams illustrating the relationship between the shape of the incident surface and the form of light propagating inside the optical element 52. Figure 9(a) shows the case where the shape of the incident surface 52a1 is a paraboloid of revolution. Figure 9(b) shows the case where the shape of the incident surface 52a2 is a rotating bipolar surface.

[0090] As can be seen from Figure 9(a), if the shape of the incident surface 52a1 is a paraboloid of revolution, the light propagating inside the optical element 52 can be made closer to parallel light. As can be seen from Figure 9(b), even if the shape of the incident surface 52a2 is a rotating bipolar surface, the light propagating inside the optical element 52 can be made closer to parallel light.

[0091] However, as is clear from comparing section D in Figure 9(a) and section E in Figure 9(b), if the shape of the incident surface 52a2 is a rotating bipolar surface, the light propagating inside the optical element 52 can be made closer to parallel light than if the shape of the incident surface 52a1 were a rotating paraboloid. Therefore, it is more preferable that the shape of the incident surface 52a2 be a rotating bipolar surface.

[0092] A revolutionary dipole, a type of revolutionary quadratic surface, can be expressed by the following equation.

number

[0093] In the case of a rotating bipolar surface, the conic constant is "k < -1". In this case, according to the inventors' findings, it is preferable to set the curvature to 0.3 or more and 1 or less, and the conic constant to -4 or more and less than -1. In this way, the light propagating inside the optical element 52 can be made closer to parallel light, and the light from the light-emitting element can be efficiently incident in the region facing the emission surface 52e.

[0094] As described above, since the light-emitting module 20 has multiple light-emitting elements 22 positioned at rotationally symmetrical locations on the circumference of the vehicle lighting device 1 with respect to its central axis 1a, it is possible to obtain a light distribution characteristic having a luminous intensity distribution (symmetrical luminous intensity distribution) in which the light irradiation angle of the luminous intensity distribution is approximately the same in the horizontal direction HH and the vertical direction VV. Therefore, the versatility of the light-emitting module 20 can be improved.

[0095] Furthermore, the optical element 52 has a light distribution characteristic that has a luminous intensity distribution with different light irradiation angles in the horizontal direction HH and the vertical direction VV (an asymmetrical luminous intensity distribution) (for example, a light distribution characteristic in which the light irradiation angle of the luminous intensity distribution in the horizontal direction HH is wider than the light irradiation angle of the luminous intensity distribution in the vertical direction VV).

[0096] Furthermore, since the shape of the incident surface 52a of the optical element 52 is a paraboloid of revolution or a dipole of revolution, the light propagating inside the optical element 52 can be made closer to parallel light. Therefore, the optical design of the exit surface 52e becomes easier, and it becomes easier to obtain the desired light distribution characteristics.

[0097] In other words, with the vehicle lighting device 1 according to this embodiment, the versatility of the light-emitting module 20 can be maintained, and a light distribution characteristic having an asymmetrical luminous intensity distribution in the horizontal and vertical directions can be obtained.

[0098] (Vehicle lighting fixtures) In one embodiment of the present invention, a vehicle lighting fixture 100 equipped with a vehicle lighting device 1 can be provided. The above-described vehicle lighting device 1 and its variations (for example, those in which a person skilled in the art has appropriately added, deleted, or modified components, and which possess the features of the present invention) can all be applied to the vehicle lighting fixture 100.

[0099] In the following explanation, we will use the example that the vehicle lighting fixture 100 is a rear combination light installed on an automobile. However, the vehicle lighting fixture 100 is not limited to a rear combination light installed on an automobile. The vehicle lighting fixture 100 can be any vehicle lighting fixture installed on an automobile, railway vehicle, etc.

[0100] Figure 10 is a schematic partial cross-sectional view illustrating a vehicle lighting fixture 100. As shown in Figure 10, the vehicle lighting fixture 100 includes, for example, a vehicle lighting device 1, a housing 101, a cover 102, an optical element 103, a sealing member 104, and a connector 105.

[0101] The vehicle lighting device 1 is mounted on the housing 101. The housing 101 holds the mounting portion 11. The housing 101 has a box shape with one end open. The housing 101 is made of, for example, a resin that does not transmit light. A mounting hole 101a is provided on the bottom surface of the housing 101 into which the portion of the mounting portion 11 with the bayonet 12 is inserted. A recess is provided around the periphery of the mounting hole 101a into which the bayonet 12 provided on the mounting portion 11 is inserted. Although the example shows the mounting hole 101a being directly provided on the housing 101, a mounting member having the mounting hole 101a may also be provided on the housing 101.

[0102] When attaching the vehicle lighting device 1 to the vehicle lamp 100, the portion of the mounting part 11 with the bayonet 12 is inserted into the mounting hole 101a, and the vehicle lighting device 1 is rotated. Then, for example, the bayonet 12 is held in place by a fitting portion provided on the periphery of the mounting hole 101a. This type of mounting method is called a twist lock.

[0103] The cover 102 is provided to close the opening of the housing 101. The cover 102 is made of a light-transmitting resin or the like. The cover 102 may also have functions such as a lens.

[0104] Light emitted from the vehicle lighting device 1 (optical unit 50) enters the optical element 103. The optical element 103 performs functions such as reflection, diffusion, guidance, focusing, and formation of a predetermined light distribution pattern of the light emitted from the vehicle lighting device 1 (optical unit 50). For example, the optical element 103 illustrated in Figure 10 is a reflector. In this case, the optical element 103 reflects the light emitted from the vehicle lighting device 1 (optical unit 50) to form a predetermined light distribution pattern.

[0105] The sealing member 104 is provided between the flange 13 and the housing 101. The sealing member 104 is annular in shape and is made of an elastic material such as rubber or silicone resin.

[0106] When the vehicle lighting device 1 is attached to the vehicle lamp 100, the sealing member 104 is sandwiched between the flange 13 and the housing 101. Therefore, the sealing member 104 can seal the internal space of the housing 101. In addition, the elastic force of the sealing member 104 presses the bayonet 12 against the housing 101. Therefore, it is possible to prevent the vehicle lighting device 1 from detaching from the housing 101.

[0107] The connector 105 is fitted onto the ends of the multiple power supply terminals 31 that are exposed inside the connector holder 15. The connector 105 is electrically connected to a lighting circuit and the like, which are located outside the vehicle lighting fixture 100. Therefore, by fitting the connector 105 onto the ends of the multiple power supply terminals 31, the lighting circuit and the light-emitting element 22 can be electrically connected.

[0108] Furthermore, the connector 105 is provided with a sealing member 105a. When the connector 105 having the sealing member 105a is inserted into the connector holder 15, the inside of the connector holder 15 is sealed to be watertight.

[0109] Although several embodiments of the present invention have been illustrated above, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. Furthermore, the embodiments described above can be implemented in combination with each other.

[0110] The following are additional notes regarding the embodiments described above.

[0111] (Note 1) Socket and; A light-emitting module having at least one light-emitting element is provided on one end side of the socket; An optical element provided on one end side of the socket and facing the light-emitting element; It is equipped with, The aforementioned optical element is At least one incident surface having a convex curved surface protruding toward the light-emitting element side; Opposite the incident surface, there is an exit surface on which a plurality of lens portions are arranged in a row; It has, The aforementioned convex curved surface is a paraboloid of revolution or a dipole of revolution, A vehicle lighting device in which the luminous intensity distribution of light emitted from the emission surface in a first direction perpendicular to the central axis of the vehicle lighting device is different from the luminous intensity distribution in a second direction perpendicular to the central axis and the first direction.

[0112] (Note 2) When viewed from a direction along the central axis, the shape of each of the multiple lens portions is approximately rhombic. The vehicle lighting device according to Appendix 1, wherein the length of the diagonal of the lens portion in the first direction is longer than the length of the diagonal of the lens portion in the second direction.

[0113] (Note 3) The vehicle lighting device according to Appendix 1 or 2, wherein the light-emitting surface of the lens portion is a convex curved surface or a concave curved surface.

[0114] (Note 4) The light-emitting module has a plurality of light-emitting elements, which are positioned at rotationally symmetrical locations on the circumference with respect to the central axis. The optical element has a plurality of incident surfaces, Each of the plurality of incident surfaces faces one of the light-emitting elements, A vehicle lighting device according to any one of the appendices 1 to 3, wherein, when viewed from a direction along the central axis, the vertex of the incident surface coincides with the center of the light-emitting surface of the light-emitting element.

[0115] (Note 5) A vehicle lighting device as described in any one of the appendices 1 to 4; The housing on which the aforementioned vehicle lighting device is mounted; It is equipped with, The first direction is the vertical direction. The second direction is horizontal for vehicle lighting fixtures. [Explanation of Symbols]

[0116] 1 Vehicle lighting device, 1a central axis, 10 socket, 11 mounting part, 20 light-emitting module, 21 substrate, 22 light-emitting element, 50 optical part, 50a central axis, 52 optical element, 52a incident surface, 52e exit surface, 52k lens part, 100 vehicle lamp, 101 housing, HH horizontal direction, VV vertical direction

Claims

1. Socket and; A light-emitting module having at least one light-emitting element is provided on one end side of the socket; An optical element provided on one end side of the socket and facing the light-emitting element; It is equipped with, The aforementioned optical element is At least one incident surface having a convex curved surface protruding toward the light-emitting element side; Opposite the incident surface, there is an exit surface on which a plurality of lens portions are arranged in a row; It has, The aforementioned convex curved surface is a paraboloid of revolution or a dipole of revolution, A vehicle lighting device in which the luminous intensity distribution of light emitted from the emission surface in a first direction perpendicular to the central axis of the vehicle lighting device is different from the luminous intensity distribution in a second direction perpendicular to the central axis and the first direction.

2. When viewed from a direction along the central axis, the shape of each of the multiple lens portions is approximately rhombic. The vehicle lighting device according to claim 1, wherein the length of the diagonal of the lens portion in the first direction is longer than the length of the diagonal of the lens portion in the second direction.

3. The vehicle lighting device according to claim 1 or 2, wherein the light-emitting surface of the lens portion is a convex curved surface or a concave curved surface.

4. The light-emitting module has a plurality of light-emitting elements, which are positioned at rotationally symmetrical locations on the circumference with respect to the central axis. The optical element has a plurality of incident surfaces, Each of the plurality of incident surfaces faces one of the light-emitting elements, The vehicle lighting device according to claim 1 or 2, wherein, when viewed from a direction along the central axis, the vertex of the incident surface coincides with the center of the light emission surface of the light-emitting element.

5. A vehicle lighting device according to claim 1 or 2; A housing on which the aforementioned vehicle lighting device is attached; It is equipped with, The first direction is the vertical direction. The second direction is horizontal, which is the direction of vehicle lighting.

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