Vehicle lighting device and vehicle lamp

Abstract

To provide a lighting device for a vehicle which can enlarge a light distribution angle, and a lamp for the vehicle.SOLUTION: A lighting device for a vehicle comprises an incident part 31 arranged at an emission side of the light of a light emitting element, and an emission part 32 for covering the incident part 31. The incident part 31 has a first recess 31a which is opened at an end part of a side opposite to the light emitting element side. A center region 31a1 of a bottom face of the first recess 31a is substantially parallel with a first face of a first baseboard on which the light emitting element is arranged. A peripheral region 31a2 of the bottom face of the first recess 31a is protrusive inclination face which is constituted of a curved line. The emission part 32 has a second recess 32a opened at the end part of the side opposite to the light emitting element side, and opposing the first recess 31a. A center region 32a1 of a bottom face of the second recess 32a is substantially parallel with the center region 31a1 of the bottom face of the first recess 31a. A peripheral region 32a2 of the bottom face of the second recess is a protrusive inclination face which is constituted of a curved line.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] FIELD An embodiment of the present invention relates to a vehicle lighting device and a vehicle lamp. [Background technology]

[0002] Wedge base bulbs, which do not have a base, are used in vehicle lighting devices. Wedge base bulbs are incandescent bulbs. Therefore, from the viewpoints of power saving and long life, wedge base bulbs are being replaced with vehicle lighting devices equipped with light-emitting diodes.

[0003] The wedge base bulb is installed by pushing it into a socket provided in the vehicle lamp. When a vehicle lighting device equipped with a light-emitting diode is used instead of the wedge base bulb, it is preferable to be able to use the socket that the wedge base bulb was installed in as is.

[0004] For this reason, a vehicle lighting device has been proposed that includes a substrate on which a light-emitting diode is mounted and a housing to which a pair of leads (terminals) is attached. If the vehicle lighting device includes a housing to which a pair of leads is attached, the portion of the housing to which the pair of leads is attached can be attached to the socket in which the wedge base light bulb was previously attached. This makes it easy to replace the wedge base light bulb with a vehicle lighting device that includes a light-emitting diode.

[0005] However, because wedge base bulbs are incandescent bulbs, they have a wide luminous intensity distribution angle. In contrast, LEDs have a narrower luminous intensity distribution angle than wedge base bulbs. Therefore, when wedge base bulbs are replaced with vehicle lighting devices equipped with LEDs, the light distribution characteristics change significantly, which can cause discomfort to drivers and interfere with the intended use.

[0006] In this case, the light distribution angle can be increased by providing a hemispherical cover that covers the light-emitting side of the light-emitting diode. However, simply providing a hemispherical cover leaves room for improvement in terms of increasing the light distribution angle. Therefore, there is a need to develop a technology that can further increase the light distribution angle. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-105652 Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a vehicle lighting device and a vehicle lamp that can increase the light distribution angle. [Means for solving the problem]

[0009] A vehicle lighting device according to an embodiment includes: a first substrate having a first surface and a second surface opposite to the first surface; a light-emitting element provided on the first surface of the first substrate; a second substrate provided on the second surface of the first substrate and extending in a direction substantially perpendicular to the second surface; and a light distribution section having an incident section provided on the light-emitting side of the light-emitting element and an exit section covering the incident section. The incident section has a first recess that opens at an end opposite to the light-emitting element side. A central region of the bottom surface of the first recess is substantially parallel to the first surface of the first substrate. A peripheral region of the bottom surface of the first recess is a convex inclined surface formed by curves. The exit section opens at an end opposite to the light-emitting element side, In a direction along the central axis of the light distribution section, the first recess; line up The first recess has a second recess, a central region of the bottom surface of the second recess that is substantially parallel to the central region of the bottom surface of the first recess, and a peripheral region of the bottom surface of the second recess that is a convex inclined surface formed of curves. The angle between a tangent to the center position of the peripheral region of the bottom surface of the second recess and the central axis of the light distribution section is smaller than the angle between a tangent to the center position of the peripheral region of the bottom surface of the first recess and the central axis of the light distribution section. [Effects of the Invention]

[0010] According to the embodiments of the present invention, it is possible to provide a vehicle lighting device and a vehicle lamp that can increase the light distribution angle. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic exploded view illustrating a vehicle lighting device according to an embodiment of the present invention; [Figure 2] 2 is a schematic diagram of the vehicle lighting device in FIG. 1 as viewed from one side in the Y direction. [Figure 3] 2 is a schematic diagram of the vehicle lighting device in FIG. 1 as viewed from the other side in the Y direction. [Figure 4] FIG. 2 is a schematic perspective view illustrating a holding portion. [Figure 5] 10 is a schematic perspective view illustrating the electrical connection between a light-emitting portion and a connection portion. FIG. [Figure 6] FIG. 2 is a schematic side view illustrating a light distribution unit. [Figure 7] FIG. 2 is a schematic diagram illustrating the function of a light distribution unit. [Figure 8] 10 is a table illustrating the effect of the light distribution unit. [Figure 9] 1 is a schematic diagram illustrating a vehicle lamp according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments will be illustrated with reference to the drawings. In the drawings, like components are designated by like reference numerals and detailed descriptions thereof will be omitted where appropriate. In addition, arrows X, Y, and Z in each figure represent three mutually orthogonal directions. For example, the Z direction is the direction in which the vehicle lighting device is inserted into a socket provided in a vehicle lamp. The X direction is the width direction of the connection portion of the vehicle lighting device. The Y direction is the thickness direction of the connection portion of the vehicle lighting device. In addition, in this specification, the term "approximately" includes, for example, differences on the order of manufacturing error.

[0013] The vehicle lighting device according to this embodiment is a vehicle lighting device that can be attached to a socket provided in a vehicle lamp. Examples of vehicle lighting devices include those used as room lamps, meter lamps, reading lights, brake lights, turn signals, tail lights, etc., which are provided in automobiles, railroad cars, etc. However, the uses of vehicle lighting devices are not limited to these.

[0014] FIG. 1 is a schematic exploded view illustrating a vehicle lighting device 1 according to the present embodiment. FIG. 2 is a schematic diagram of the vehicle lighting device 1 in FIG. 1 as viewed from one side in the Y direction. FIG. 3 is a schematic diagram of the vehicle lighting device 1 in FIG. 1 as viewed from the other side in the Y direction. As shown in FIGS. 1 to 3, a vehicle lighting device 1 includes, for example, a light emitting section 10, a connection section 20, and a light distribution section 30.

[0015] The light emitting section 10 includes a substrate 11 (corresponding to an example of a first substrate) and a light emitting element 12, for example. The substrate 11 is, for example, plate-shaped and has a surface 11a (corresponding to an example of a first surface) and a surface 11b (corresponding to an example of a second surface) opposite to the surface 11a. The planar shape of the substrate 11 is, for example, a part of a circle including a center point. However, the planar shape of the substrate 11 is not limited to the example shown. The planar shape of the substrate 11 may be, for example, a polygon. The planar shape of the substrate 11 can be changed as appropriate depending on the number and arrangement of the light-emitting elements 12.

[0016] The substrate 11 can be made of an insulating material. The substrate 11 is made of, for example, an inorganic material such as ceramics (e.g., aluminum oxide or aluminum nitride), or an organic material such as paper phenol or glass epoxy. The substrate 11 may also be, for example, a metal core substrate in which the surface of a metal plate is coated with an insulating material.

[0017] When the light emitting element 12 generates a large amount of heat, it is preferable to form the substrate 11 using a material with high thermal conductivity from the viewpoint of heat dissipation. Examples of materials with high thermal conductivity include ceramics such as aluminum oxide and aluminum nitride, highly thermally conductive resins, and metal core substrates. Highly thermally conductive resins are, for example, resins such as PET (Polyethylene terephthalate) and nylon mixed with fillers such as aluminum oxide.

[0018] The thickness of the substrate 11 is, for example, about 0.5 mm to 3.0 mm, but the thickness of the substrate 11 is not limited to the example given and can be changed as appropriate.

[0019] A wiring pattern is provided on a surface 11a of the substrate 11 opposite to the connection portion 20. The light emitting element 12 is electrically connected to the wiring pattern. The wiring pattern is made of a low resistance metal such as copper, aluminum, or silver.

[0020] At least one light emitting element 12 can be provided on the surface 11 a of the substrate 11 . The light emitting element 12 may be, for example, a light emitting diode, an organic light emitting diode, a laser diode, or the like. The light emitting element 12 may be, for example, a surface-mounted light emitting element such as a PLCC (Plastic Leaded Chip Carrier) type. The light emitting element 12 may also be, for example, a bullet-type light emitting element having leads. The light emitting element 12 illustrated in FIG. 1 is a surface-mounted light emitting element.

[0021] The light-emitting element 12 may also be a chip-type light-emitting element. The chip-type light-emitting element may be mounted, for example, by COB (Chip On Board). In this case, the surface 11a of the substrate 11 may be provided with the following components: chip-type light-emitting element, wiring electrically connecting the chip-type light-emitting element to the wiring pattern, a frame-shaped member surrounding the chip-type light-emitting element and wiring, and a sealing portion disposed inside the frame-shaped member and covering the chip-type light-emitting element and wiring. The sealing portion may also contain a phosphor. The phosphor may be, for example, a YAG-based phosphor (yttrium-aluminum-garnet-based phosphor). Note that the type of phosphor is not limited to the examples given. The type of phosphor may be appropriately changed to obtain a desired emission color depending on the application of the vehicle lighting device 1.

[0022] The light emitting surface of the light emitting element 12 may be, for example, approximately parallel to the surface 11a of the substrate 11. For example, the light emitting element 12 mainly emits light in a direction perpendicular to the surface 11a of the substrate 11. The number, size, arrangement, etc. of the light-emitting elements 12 are not limited to those exemplified, and can be changed as appropriate depending on the size and use of the vehicle lighting device 1. When multiple light-emitting elements 12 are provided, the multiple light-emitting elements 12 can be connected in series.

[0023] The connection section 20 includes, for example, a substrate 21 (corresponding to an example of a second substrate) and a circuit component 22. The substrate 21 has, for example, a plate shape and extends in a direction approximately perpendicular to the surface 11b of the substrate 11. When viewed from the Y direction, the shape of the substrate 21 can be, for example, approximately rectangular. The substrate 21 is provided on the surface 11b of the substrate 11. For example, the end surface of the substrate 21 on the substrate 11 side can be adhered to the surface 11b of the substrate 11.

[0024] To facilitate replacement with a wedge base bulb, the width W of the substrate 21 can be set to 5.0 mm to 15.0 mm, for example, approximately 10.0 mm. However, the width W of the substrate 21 is not limited to the example shown, and can be changed appropriately depending on the dimensions of the recess of the socket 101 into which the substrate 21 is inserted. The width W of the substrate 21 is the dimension of the substrate 21 in the X direction.

[0025] The thickness T of the substrate 21 can be set to, for example, about 0.1 mm to 3.0 mm. In this case, if the thickness T of the substrate 21 is thin, the manufacturing cost of the substrate 21, and therefore the manufacturing cost of the vehicle lighting device 1, can be reduced. However, if the thickness T of the substrate 21 is made too thin, there is a risk that the substrate 21 will be damaged, for example, when inserting the vehicle lighting device 1 into the socket 101. Therefore, the thickness T of the substrate 21 is preferably set to about 0.1 mm to 2.0 mm. If the thickness T of the substrate 21 is within this range, it is possible to reduce the manufacturing cost of the substrate 21 and to prevent damage to the substrate 21. The thickness T of the substrate 21 is the dimension of the substrate 21 in the Y direction.

[0026] The material of the substrate 21 can be, for example, the same as the material of the substrate 11 described above. Heat generated in the light emitting element 12 is transferred to the substrate 21 via the substrate 11, and is then released from the substrate 21 to the outside via the socket 101. Therefore, in consideration of suppressing the temperature rise of the light emitting element 12, it is preferable to form the substrate 21 using a material with high thermal conductivity. Examples of materials with high thermal conductivity include ceramics such as aluminum oxide and aluminum nitride, highly thermally conductive resins, and metal core substrates. In this case, the material of the substrate 21 may be the same as or different from the material of the substrate 11.

[0027] A wiring pattern can be provided on the surface 21a of the substrate 21. The wiring pattern can be made of a low-resistance metal such as copper, aluminum, or silver. As shown in FIGS. 1 and 2 , a pair of terminals 21a1 may be provided on the surface 21a of the substrate 21. The pair of terminals 21a1 are electrically connected to the wiring pattern. For example, the pair of terminals 21a1 may be formed integrally with the wiring pattern. For example, the material of the pair of terminals 21a1 may be the same as the material of the wiring pattern. The pair of terminals 21a1 are provided near the end of the substrate 21 opposite the light-emitting unit 10 side. When the substrate 21 is attached to the socket 101, each of the pair of terminals 21a1 is electrically connected to socket terminals 101a and 101b provided on the socket 101. In this case, by electrically connecting the socket terminal 101a provided on the socket 101 to one of the terminals 21a1, the socket terminal 101a can be electrically connected to an electrode of one polarity of the light-emitting element 12 via the wiring pattern provided on the substrate 21 and the wiring pattern provided on the substrate 11. Furthermore, by electrically connecting the socket terminal 101b to the other terminal 21a1, the socket terminal 101b can be electrically connected to the electrode of the other polarity of the light-emitting element 12 via the wiring pattern provided on the substrate 21 and the wiring pattern provided on the substrate 11.

[0028] 3, a pair of terminals 21a1 can also be provided on surface 21b of substrate 21. Terminal 21a1 provided on surface 21b can be provided in a position facing terminal 21a1 provided on surface 21a. Terminal 21a1 provided on surface 21b can be electrically connected to terminal 21a1 provided on surface 21a through a conductive via.

[0029] In this case, the pair of terminals 21a1 can be provided on at least one of the surfaces 21a and 21b of the substrate 21. However, if the terminals 21a1 are provided on the surfaces 21a and 21b, the reliability of the electrical connection between the pair of terminals 21a1 and the socket terminals 101a and 101b provided on the socket 101 can be improved.

[0030] When the vehicle lighting device 1 (substrate 21) is attached to the socket 101 of the vehicle lamp 100, the portion of the substrate 21 where the terminal 21a1 is provided is sandwiched between socket terminals 101a and 101b provided on the socket 101. The vehicle lighting device 1 is held by the socket terminals 101a and 101b due to the elastic force of the socket terminals 101a and 101b. The vehicle lighting device 1 is also electrically connected to an external power source or the like via the socket terminals 101a and 101b.

[0031] In this case, the elastic force of the socket terminals 101a, 101b increases or decreases depending on the amount of deformation of the socket terminals 101a, 101b. For example, the elastic force of the socket terminals 101a, 101b varies depending on the thickness of the portion of the vehicle lighting device 1 that is sandwiched between the socket terminals 101a, 101b (the thickness of the substrate 21 and the thickness of the terminals 21a1). Therefore, the force holding the vehicle lighting device 1 may be weakened due to manufacturing errors in the dimensions of the socket terminals 101a, 101b, the thickness of the substrate 21, the thickness of the terminals 21a1, and the like.

[0032] Since the vehicle lighting device 1 is subjected to vibrations caused by driving and vibrations from the engine, etc., if the force holding the vehicle lighting device 1 weakens, the position of the vehicle lighting device 1 may shift, changing the light distribution characteristics, reducing the reliability of the electrical connection with an external power source, etc., or the vehicle lighting device 1 may fall off from the socket 101.

[0033] Therefore, the vehicle lighting device 1 is provided with a holding portion 21a2. FIG. 4 is a schematic perspective view illustrating the holding portion 21a2. 1 to 4, the holding portion 21a2 is provided between the terminal 21a1 and the end of the surface 21a (21b) of the substrate 21 on the side opposite to the light-emitting portion 10. Although a gap is provided between the holding portion 21a2 and the terminal 21a1 in the example shown, the holding portion 21a2 and the terminal 21a1 may be in contact with each other. For example, the holding portion 21a2 may be formed on the terminal 21a1, or may be formed alongside the terminal 21a1 and integral with the terminal 21a1.

[0034] When the holding portion 21a2 is formed apart from the terminal 21a1 or formed on the terminal 21a1, the holding portion 21a2 can be formed from, for example, a metal with a low melting point such as solder, a resin, etc. For example, the holding portion 21a2 containing solder or resin can be formed using screen printing, a dispenser, a hot melt device, etc.

[0035] When the holding portion 21a2 is formed integrally with the terminal 21a1, the holding portion 21a2 can be formed integrally with, for example, the terminal 21a1 and the wiring pattern by, for example, screen printing, plating, or the like.

[0036] When the vehicle lighting device 1 (substrate 21) is attached to the socket 101 of the vehicle lamp 100, the curved portions near the tips of the socket terminals 101a and 101b come into contact with the terminal 21a1 (see FIG. 9). In this case, the holding portion 21a2 is located between the curved portions of the socket terminals 101a and 101b and the end of the substrate 21 opposite to the light-emitting portion 10 side.

[0037] As described above, when vibration is applied to the vehicle lighting device 1, the position of the vehicle lighting device 1 may change. In this case, the vehicle lighting device 1 generally tends to move in a direction in which it is removed from the socket 101. Therefore, as shown in FIG. 4, the thickness of the holding portion 21a2 is made thicker than the thickness of the terminal 21a1. Therefore, a step is provided between the holding portion 21a2 and the terminal 21a1.

[0038] If a step is provided between the holding portion 21a2 and the terminal 21a1, when the vehicle lighting device 1 moves in the direction (Z direction) to be removed from the socket 101, curved portions near the tips of the socket terminals 101a and 101b are caught on the step. Therefore, the vehicle lighting device 1 can be prevented from moving in the direction to be removed from the socket 101.

[0039] FIG. 5 is a schematic perspective view illustrating the electrical connection between the light-emitting unit 10 and the connection unit 20. As shown in FIG. As shown in FIG. 5, the wiring pattern provided on the substrate 11 and the wiring pattern provided on the substrate 21 are electrically connected by a pair of joints 23 near the connection portion between the substrates 11 and 21. The pair of joints 23 are formed, for example, by soldering. That is, the wiring pattern provided on the substrate 21 is electrically connected to the wiring pattern provided on the substrate 11 via the pair of joints 23. Note that, as shown in FIGS. 2 and 3, in the vehicle lighting device 1, the pair of joints 23 are provided on the surface 21b of the substrate 21, but it is sufficient that the joints 23 are provided on at least one of the surfaces 21a and 21b of the substrate 21. Furthermore, for example, one of the joints 23 may be provided on the surface 21a of the substrate 21, and the other joint 23 may be provided on the surface 21b of the substrate 21.

[0040] The circuit component 22 may be, for example, a diode 22a, a resistor 22b, a capacitor 22c, or the like. Because a wedge base bulb is an incandescent bulb, one of the pair of leads can be electrically connected to the positive side of a power source, and the other lead can be electrically connected to the negative side of the power source. In other words, a wedge base bulb has no polarity. In contrast, a light-emitting element 12, such as a light-emitting diode, has a polarity. Therefore, a diode can be provided to prevent reverse voltage from being applied to the light-emitting element 12.

[0041] Furthermore, in consideration of replacing a wedge base bulb, it is preferable to provide a non-polar circuit in the vehicle lighting device 1. If the vehicle lighting device 1 is provided with a non-polar circuit, like a wedge base bulb, there will be no directionality when it is installed in the socket 101. This makes the installation of the vehicle lighting device 1 easier.

[0042] For example, if a bridge circuit (bridge diode) is configured using four diodes, a non-polar circuit can be provided in the vehicle lighting device 1. The diode 22a illustrated in FIG. 3 is a so-called two-element diode. If the diode 22a is a two-element diode, a bridge circuit can be configured using two diodes 22a, thereby reducing the mounting area. This makes it easy to match the width dimension W of the board 21 to the width dimension of the portion where the leads of the wedge base bulb are provided.

[0043] Resistor 22b can be, for example, a surface-mount resistor, a resistor with leads (metal oxide film resistor), or a film resistor formed using a screen printing method. The resistor 22b illustrated in Figures 1 and 2 is a surface-mount resistor. A surface-mount resistor reduces the mounting area, making it easier to match the width W of substrate 21 to the width of the lead-mounted portion of the wedge-base bulb.

[0044] Here, since there is variation in the forward voltage characteristics of the light-emitting element 12, if the voltage applied between the anode terminal and the ground terminal is constant, variation occurs in the brightness (luminous flux, luminance, luminous intensity, illuminance) of the light emitted from the light-emitting element 12. Therefore, to keep the brightness of the light emitted from the light-emitting element 12 within a predetermined range, the value of the current flowing through the light-emitting element 12 is controlled to be within a predetermined range by using the resistor 22b connected in series with the light-emitting element 12. In this case, by changing the resistance value of the resistor 22b, the value of the current flowing through the light-emitting element 12 can be controlled to be within the predetermined range.

[0045] For example, if the resistor 22b is a surface-mount resistor or a resistor with leads, the resistor 22b is selected to have an appropriate resistance value according to the forward voltage characteristics of the light-emitting element 12. For example, if the resistor 22b is a film resistor, the resistance value can be increased by removing a portion of the resistor 22b.

[0046] The resistor 22b can also serve to prevent an excessive current from flowing through the light emitting element 12. The number, size, arrangement, etc. of the resistors 22b are not limited to those exemplified, and can be changed as appropriate depending on the number and specifications of the light emitting elements 12, etc.

[0047] Capacitor 22c can be provided, for example, to counter noise or smooth voltage. Capacitor 22c can be, for example, a surface-mounted capacitor 22c. If surface-mounted capacitor 22c is used, the mounting area can be reduced, making it easy to install capacitor 22c at any position.

[0048] 1 to 3, as an example, diode 22a provided on surface 21b of substrate 21, resistor 22b provided on surface 21a of substrate 21, and capacitor 22c provided on surface 11a of substrate 11 are shown, but the arrangement of diode 22a, resistor 22b, and capacitor 22c is not limited to the illustrated example. For example, diode 22a, resistor 22b, and capacitor 22c may be provided on any of surfaces 11a, 11b of substrate 11 and surfaces 21a, 21b of substrate 21.

[0049] Furthermore, the circuit components 22 are not limited to those exemplified above. For example, the circuit components 22 can be passive or active elements used to configure a light-emitting circuit having the light-emitting element 12. In addition to the above, the circuit components 22 can also be, for example, positive temperature coefficient thermistors, negative temperature coefficient thermistors, inductors, surge absorbers, varistors, transistors such as FETs and bipolar transistors, Zener diodes, integrated circuits, and arithmetic elements. The integrated circuit can include, for example, at least one of a flashing circuit, a constant current circuit, and a lighting circuit (drive circuit).

[0050] At least a portion of the circuit component 22 can also be provided in the housing 102 of the vehicle lamp 100 to which the vehicle lighting device 1 is attached. In this way, the configuration of the vehicle lighting device 1 can be simplified, thereby reducing the cost of the vehicle lighting device 1. However, if the circuit component 22 is provided in the vehicle lighting device 1, the vehicle lighting device 1 can be protected and multi-functionalized even if the socket in which the wedge base bulb was attached is used as is.

[0051] Here, the wedge base bulb is an incandescent bulb and has a large light distribution angle. In contrast, light emitting element 12 mainly emits light in a direction perpendicular to surface 11a of substrate 11. Therefore, the light distribution characteristics of light emitting element 12 are significantly different from those of the wedge base bulb.

[0052] When a wedge base bulb is replaced with a vehicle lighting device equipped with a light-emitting element 12, if the light distribution characteristics change significantly, the driver may feel uncomfortable or the device may be unable to be used properly.

[0053] Therefore, in order to make the light distribution characteristics of the vehicle lighting device 1 closer to those of a wedge base bulb, a light distribution section 30 is provided. As shown in Figures 1 to 3, the light distribution section 30 is provided on the light emission side of the light-emitting section 10. For example, the light distribution section 30 can be provided so as to cover the surface 11a of the substrate 11.

[0054] The light distribution unit 30 allows a portion of the light emitted from the light-emitting element 12 to exit as is, and also reflects a portion of the light emitted from the light-emitting element 12 to emit reflected light. In other words, the light distribution unit 30 diffuses the light emitted from the light-emitting element 12 to increase the light distribution angle.

[0055] FIG. 6 is a schematic side view illustrating the light distribution section 30. As shown in FIG. As shown in FIGS. 2, 3, and 6, the light distribution section 30 has an incident section 31 and an exit section 32. The incident portion 31 has a cylindrical shape and is provided on the light emitting side of the light emitting element 12 . A recess 31a (corresponding to an example of a first recess) is provided at the end of the incident portion 31 opposite the light emitting element 12 side. The recess 31a opens at the end of the incident portion 31 opposite the light emitting element 12 side. A central region 31a1 of the bottom surface of the recess 31a is flat. The central region 31a1 is approximately parallel to the surface 11a of the substrate 11. The portion of the incident portion 31 where the central region 31a1 is provided is flat and is located directly above the light emitting element 12.

[0056] The peripheral region 31a2 of the bottom surface of the recess 31a is a convex inclined surface formed by curves. The portion of the incident portion 31 where the peripheral region 31a2 is provided can function as a convex lens. For example, the peripheral region 31a2 of the incident portion 31 collects light with a polar angle θ of 30° to 60°, causing uniform light to enter the exit portion 32. The polar angle θ is the angle between the normal (the central axis 1a of the vehicle lighting device 1) passing through the center of the light exit surface of the light-emitting element 12 and the direction in which the light is emitted (see FIG. 7).

[0057] The distance between the end of the incident portion 31 opposite to the light emitting element 12 side and the light emission surface of the light emitting element 12 is preferably 2.5 mm or more. In this way, the amount of light incident on the incident portion 31 can be made appropriate.

[0058] The diameter of the incident portion 31 may be, for example, approximately 7.6 mm. The inclination angle at the center position of the peripheral region 31a2 of the incident portion 31 may be approximately 63.4°. The connection position between the central region 31a1 and the peripheral region 31a2 may be a position where the polar angle θ is 60°.

[0059] The light exit portion 32 has a cylindrical shape and covers the light entrance portion 31. In this case, the central axis 31c of the light entrance portion 31 and the central axis 32c of the light exit portion 32 can be made to overlap with a normal (the central axis 1a of the vehicle lighting device 1) passing through the center of the light exit surface of the light emitting element 12.

[0060] A recess 32a (corresponding to an example of a second recess) is provided at the end of the emission section 32 opposite to the light-emitting element 12 side. The recess 32a faces the recess 31a of the incidence section 31. The recess 32a is provided concentrically with the recess 31a of the incidence section 31. The recess 32a opens at the end of the emission section 32 opposite to the light-emitting element 12 side. A central region 32a1 of the bottom surface of the recess 32a is flat. The central region 32a1 of the emission section 32 is approximately parallel to the central region 31a1 of the incidence section 31. The portion of the emission section 32 where the central region 32a1 is provided is flat and is located directly above the central region 31a1 of the incidence section 31.

[0061] As shown in Figure 6, the angle θ2 between the tangent at the center position of the peripheral region 32a1 of the exit portion 32 and the central axis 30c of the light distribution portion 30 is smaller than the angle θ1 between the tangent at the center position of the peripheral region 31a2 of the entrance portion 31 and the central axis 30c of the light distribution portion 30.

[0062] The peripheral region 32a2 of the bottom surface of the recess 32a is a convex inclined surface formed by curves. The portion of the exit portion 32 where the peripheral region 32a2 is provided can function as a concave lens. For example, the peripheral region 32a2 of the exit portion 32 reflects incident light and emits light with a polar angle θ of approximately 90° to 100°.

[0063] The distance between the end of the emission section 32 opposite to the light emitting element 12 side and the end of the incidence section 31 opposite to the light emitting element 12 side is preferably 3.3 mm or more and 5.3 mm or less. The diameter of the light exit portion 32 may be, for example, about 10 mm. The diameter of the central region 32a1 of the light exit portion 32 may be about 1.1 mm. The tilt angle at the center position of the peripheral region 32a2 of the light exit portion 32 may be about 39.2°.

[0064] Incident section 31 and exit section 32 can be made of a light-transmitting organic material such as polycarbonate resin or acrylic resin, or an inorganic material such as glass. Incident section 31 and exit section 32 may be formed separately and then assembled, or may be formed integrally.

[0065] Furthermore, at least one of the incident portion 31 and the exit portion 32 can be provided with an attachment portion 33. As shown in FIGS. 1 to 3, a pair of attachment portions 33 can be provided. The pair of attachment portions 33 extend along the side surfaces of the substrate 21. As shown in FIG. 1, the attachment portion 33 has a hole 33a. When the light distribution unit 30 is attached to the light-emitting unit 10, a protrusion 21c provided on the side surface of the substrate 21 is inserted into the hole 33a. Therefore, the light distribution unit 30 can be provided detachably to the light-emitting unit 10.

[0066] FIG. 7 is a schematic diagram illustrating the function of the light distribution unit 30. As shown in FIG. In FIG. 7, to avoid complication, the optical paths on only one side of the central axis 30c of the light distribution section 30 are depicted. In the simulation of the optical path, the light emitting element 12 is a light emitting diode with an emission surface of 3 mm×3 mm and a divergence angle of 120°. The diameter of the incident part 31 is 7.5 mm.

[0067] As described above, the portion of incident portion 31 where central region 31a1 is provided has a flat plate shape and is located directly above light emitting element 12. Therefore, as shown in FIG. 7 , light emitted from light emitting element 12 and incident on central region 31a1 passes through central region 31a1 and enters central region 32a1 of exit portion 32.

[0068] As described above, the portion of incident portion 31 where peripheral region 31a2 is provided functions as a convex lens. Therefore, as shown in Fig. 7, light emitted from light-emitting element 12 and incident on peripheral region 31a2 is bent in a direction approaching central axis 31c of incident portion 31. The light emitted from peripheral region 31a2 is incident on peripheral region 32a2 of exit portion 32.

[0069] As described above, the portion of exit portion 32 where central region 32a1 is provided is flat and located directly above central region 31a1 of entrance portion 31. Therefore, as shown in Fig. 7, light that has exited central region 31a1 of entrance portion 31 and entered central region 32a1 of exit portion 32 passes through central region 32a1 and is irradiated in the direction of central axis 32c of exit portion 32.

[0070] As described above, the portion of the exit portion 32 where the peripheral region 32a2 is provided functions as a concave lens, so that the light emitted from the peripheral region 31a2 of the entrance portion 31 and the light emitted from the central region 31a1 of the entrance portion 31 can be reflected and emitted to the side of the exit portion 32, as shown in FIG.

[0071] 7, at the interface between the side surface of the exit portion 32 and the outside air, reflected light or refracted light occurs depending on the angle of incidence. Therefore, light can be irradiated to the side of the exit portion 32 and in a direction approaching the central axis 32c of the exit portion 32.

[0072] As described above, if the light distribution section 30 is provided, it is possible to diffuse the light emitted from the light emitting element 12. Therefore, as shown in Fig. 7, it is possible to increase the polar angle θ. As a result, it is possible to increase the light distribution angle.

[0073] FIG. 8 is a table illustrating the effect of the light distribution unit 30. 8 compares the light distribution characteristics of a wedge base bulb, a vehicle lighting device equipped with a hemispherical cover and light emitting element 12, and a vehicle lighting device 1 equipped with a light distribution unit 30 and light emitting element 12. The light distribution characteristics were evaluated in terms of cd / lm (candela per lumen) at a specified extreme.

[0074] As can be seen from Figure 8, in the case of a wedge base bulb, a uniform light intensity can be obtained at angles between -100° and 100°. In other words, the light distribution angle of a wedge base bulb is large. A vehicle lighting device equipped with a hemispherical cover and light emitting element 12 will have a higher light intensity than a wedge base bulb when the angle is between -50° and 50°, but will have a lower light intensity than a wedge base bulb when the angle is between -100° and 100°. Therefore, a vehicle lighting device equipped with a hemispherical cover and light emitting element 12 will have a smaller light distribution angle and greater unevenness in light intensity than a wedge base bulb.

[0075] In contrast, the vehicle lighting device 1 including the light distribution section 30 and the light emitting element 12 can provide a substantially uniform light intensity at angles between -100° and 100°. This allows for a light distribution angle substantially equivalent to that of a wedge base bulb, and therefore a light distribution characteristic substantially equivalent to that of a wedge base bulb.

[0076] (vehicle lighting fixture 100) FIG. 9 is a schematic diagram illustrating a vehicle lamp 100 according to this embodiment. In the following, an example will be given in which one vehicle lighting device 1 is provided, but it is sufficient that at least one vehicle lighting device 1 is provided.

[0077] As shown in FIG. 9, a vehicle lamp 100 may include a vehicle lighting device 1, a socket 101, a housing 102, and a cover 103.

[0078] The socket 101 can be provided in a housing 102. The vehicle lighting device 1 (substrate 21) can be attached to the socket 101. The socket 101 is made of an insulating material such as resin. Furthermore, although FIG. 9 shows an example in which the socket 101 and the housing 102 are provided separately, the socket 101 and the housing 102 may be formed integrally.

[0079] The socket 101 may be provided with a recess that opens at one end. The vehicle lighting device 1 (substrate 21) is inserted into the recess. The recess may also be provided with a socket terminal 101a corresponding to one voltage polarity (e.g., positive) and a socket terminal 101b corresponding to the other voltage polarity (e.g., negative). As described above, as long as the vehicle lighting device 1 is provided with a non-polarity circuit, the mounting direction of the vehicle lighting device 1 (substrate 21) is not limited.

[0080] The socket terminals 101a and 101b are elastically deformable. When the substrate 21 is inserted into the recess, the socket terminals 101a and 101b are electrically connected to the terminals 21a1, respectively. Furthermore, curved portions near the tips of the socket terminals 101a and 101b come into contact with the terminals 21a1. Therefore, for example, when the vehicle lighting device 1 is subjected to vibration or the like, it is possible to prevent the position of the vehicle lighting device 1 from shifting, changing the light distribution characteristics, reducing the reliability of the electrical connection with an external power source, or causing the vehicle lighting device 1 to fall off the socket 101.

[0081] The socket terminals 101a and 101b can be electrically connected to a power source or the like provided outside the vehicle lamp 100. Note that a circuit board may be provided on at least one of the inside and outside of the housing 102, and the socket terminals 101a and 101b and the power source or the like may be electrically connected via the circuit board.

[0082] The housing 102 may be shaped like a box with one end open, for example, and may be made of a material such as a resin that does not transmit light. The cover 103 can be provided so as to cover the opening of the housing 102. The cover 103 can be formed from a light-transmitting resin or the like. The cover 103 can have a function such as a lens, or can suppress glare. The cover 103 can be provided on the housing 102 so as to be openable and closable, or so as to be detachable.

[0083] Additionally, optical elements such as reflectors and lenses may be provided inside the housing 102 .

[0084] Although several embodiments of the present invention have been described above, these embodiments are presented by way of example only and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, modifications, etc. can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as set forth in the claims. Furthermore, the above-described embodiments can be implemented in combination with each other. [Explanation of symbols]

[0085] 1 Vehicle lighting device, 10 Light-emitting portion, 11a surface, 11b surface, 12 Light-emitting element, 11 substrate, 20 Connection portion, 21 substrate, 30 Light distribution portion, 31 Incident portion, 31a Recess, 31a1 Central region, 31a2 Peripheral region, 32 Outgoing portion, 32a1 Central region, 32a2 Peripheral region, 100 Vehicle lamp, 101 Socket

Claims

1. a first substrate having a first surface and a second surface opposite the first surface; a light-emitting element provided on the first surface of the first substrate; a second substrate provided on the second surface of the first substrate and extending in a direction substantially perpendicular to the second surface; a light distribution unit having an incident portion provided on the light emission side of the light emitting element and an exit portion covering the incident portion; Equipped with the incident portion has a first recess that opens at an end opposite to the light emitting element side, a central region of a bottom surface of the first recess is approximately parallel to the first surface of the first substrate; a peripheral region of a bottom surface of the first recessed portion is a convex inclined surface formed of curves, the light emitting section has an opening at an end opposite to the light emitting element side, and a second recess aligned with the first recess in a direction along a central axis of the light distribution section; a central region of a bottom surface of the second recess is substantially parallel to the central region of the bottom surface of the first recess; a peripheral region of a bottom surface of the second recessed portion is a convex inclined surface formed of curves, A vehicle lighting device, wherein the angle between a tangent to the bottom surface of the second recess at the center position of the peripheral region and the central axis of the light distribution section is smaller than the angle between a tangent to the bottom surface of the first recess at the center position of the peripheral region and the central axis of the light distribution section.

2. The vehicle lighting device according to claim 1 , wherein the second recess is provided concentrically with the first recess.

3. The vehicle lighting device according to claim 1 , wherein the central region of the bottom surface of the second recess is smaller than the central region of the bottom surface of the first recess.

4. The vehicle lighting device according to any one of claims 1 to 3; a socket provided in the vehicle lighting device into which a second substrate is inserted; A vehicle lighting fixture equipped with:

Images