Vehicle lighting device and vehicle lighting fixture

Abstract

To provide a vehicle lighting device capable of changing a ratio in reduction of a total luminous flux in a region where a circumference temperature of a light emitting element is high, and provide a vehicle lighting fixture.SOLUTION: A vehicle lighting device contains: a socket; a substrate provided to one end part side of the socket; a light emitting element; a control element having a current driver and a current setting circuit; a first circuit of which a resistance value is changed by a circumference temperature of the light emitting element; and a second circuit of which the resistance value is changed by the circumference temperature of the light emitting element. In the current setting circuit, in a temperature region where the circumference temperature of the light emitting element exceeds a first temperature, and is higher than the first temperature and is a second temperature or lower, reduces an output currents flowing in the light emitting element in accordance with an increase of the circumference temperature of the light emitting element on the basis of the change of the resistance value of the first circuit. In a temperature region where the circumference temperature of the light emitting element exceeds the second temperature, increased is a ratio that the output current flowing in the light emitting element is reduced in accordance with an increase of the circumference temperature of the light emitting element on the basis of the change of the resistance value of the second circuit.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] From the viewpoint of energy saving and long life, vehicle lighting devices equipped with light emitting elements such as light emitting diodes are becoming more and more popular instead of vehicle lighting devices equipped with lamps having filaments. A vehicle lighting device equipped with a light emitting element has, for example, a substrate on which a light emitting element and a circuit element are mounted.

[0003] When a current flows through the light-emitting element, light is emitted from the light-emitting element, and heat is generated between the light-emitting element and the circuit element. In the case of a vehicle lighting device, the temperature of the atmosphere in which the vehicle lighting device is installed may be about 85°C. Therefore, the temperature of the light-emitting element may become too high and exceed the maximum junction temperature. If the temperature of the light-emitting element exceeds the maximum junction temperature, the light-emitting element may break down or its function may deteriorate.

[0004] For this reason, a vehicle lighting device has been proposed that includes a control element that controls the current flowing through the light-emitting element according to the ambient temperature of the light-emitting element. That is, a vehicle lighting device has been proposed that includes a control element that performs temperature derating. In an area where the ambient temperature of the light-emitting element is high, such a control element reduces the total luminous flux of the light irradiated from the light-emitting element based on the ambient temperature of the light-emitting element.

[0005] However, depending on the type and application of the vehicle lighting device, the total luminous flux for a given temperature may differ from the total luminous flux defined by temperature derating. Therefore, there has been a demand for the development of a technique that can change the rate at which the total luminous flux is reduced in a region where the ambient temperature of the light emitting element is high. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 7018124 Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved by the present invention is to provide a vehicle lighting device and a vehicle lamp that can change the rate at which the total luminous flux is reduced in an area where the ambient temperature of the light-emitting element is high. [Means for solving the problem]

[0008] A vehicle lighting device according to an embodiment includes a socket, a substrate provided on one end of the socket, a light-emitting element provided on the substrate, a control element provided on the substrate, the control element having a current driver and a current setting circuit, the control element being provided on the substrate and having an output side electrically connected to the light-emitting element and an output side electrically connected to the current driver, a first circuit provided on the substrate and electrically connected to a first input side of the current setting circuit, the resistance value of which varies with the ambient temperature of the light-emitting element, and a second circuit provided on the substrate and electrically connected to a second input side of the current setting circuit, the resistance value of which varies with the ambient temperature of the light-emitting element. In a temperature range in which the ambient temperature of the light-emitting element is higher than a first temperature and is equal to or lower than a second temperature higher than the first temperature, the current setting circuit reduces an output current flowing to the light-emitting element as the ambient temperature of the light-emitting element increases, based on a change in the resistance value of the first circuit. In a temperature region where the ambient temperature of the light-emitting element exceeds the second temperature, the current setting circuit increases the rate at which the output current flowing to the light-emitting element is reduced as the ambient temperature of the light-emitting element rises based on a change in the resistance value of the second circuit. Effect of the Invention

[0009] According to the embodiments of the present invention, it is possible to provide a vehicle lighting device and a vehicle lamp that are capable of changing the rate at which the total luminous flux is reduced in an area where the ambient temperature of the light-emitting element is high. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic perspective view illustrating a vehicle lighting device according to an embodiment of the present invention; [Diagram 2] 2 is a cross-sectional view of the vehicle lighting device taken along line AA in FIG. 1. [Diagram 3] FIG. 11 is a circuit diagram illustrating a light emission circuit. [Figure 4] 11 is a circuit diagram illustrating a light emitting circuit according to a comparative example. FIG. [Diagram 5] 11 is a graph illustrating the effects of the light-emitting circuit according to the comparative example. [Figure 6] 11 is a graph illustrating the effects of the light-emitting circuit according to the comparative example. [Figure 7] 6 is a graph illustrating the effects of the light emission circuit according to the present embodiment. [Figure 8] 10 is a graph illustrating another effect of the light emitting circuit according to the comparative example. [Figure 9] 13 is a circuit diagram illustrating a light emitting circuit according to another embodiment. FIG. [Figure 10] 11 is a graph illustrating the effect of the light emitting circuit. [Figure 11] 13 is a circuit diagram illustrating a light emitting circuit according to another embodiment. FIG. [Figure 12] 13 is a circuit diagram illustrating a light emitting circuit according to another embodiment. FIG. [Figure 13] 13 is a circuit diagram illustrating a light emitting circuit according to another embodiment. FIG. [Figure 14] 13 is a circuit diagram illustrating a light emitting circuit according to another embodiment. FIG. [Figure 15] 1 is a schematic partial cross-sectional view illustrating a vehicle lamp. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted as appropriate.

[0012] (Vehicle lighting device) The vehicle lighting device 1 according to the present embodiment can be installed in, for example, an automobile or a railcar. Examples of the vehicle lighting device 1 installed in an automobile include a front combination light (for example, a combination of a daytime running lamp (DRL), a position lamp, a turn signal lamp, etc.) and a rear combination light (for example, a combination of a stop lamp, a tail lamp, a turn signal lamp, a back lamp, a fog lamp, etc.). However, the uses of the vehicle lighting device 1 are not limited to these.

[0013] FIG. 1 is a schematic perspective view illustrating a vehicle lighting device 1 according to the present embodiment. FIG. 2 is a cross-sectional view of the vehicle lighting device 1 taken along line AA in FIG. As shown in FIGS. 1 and 2, a vehicle lighting device 1 includes a socket 10, a light emitting module 20, a power supply unit 30, and a heat transfer unit 40, for example.

[0014] The socket 10 has, for example, a mounting portion 11, a bayonet 12, a flange 13, heat dissipation fins 14, and a connector holder 15. The mounting portion 11 is provided on the surface of the flange 13 opposite to the side on which the heat dissipation fins 14 are provided. The outer shape of the mounting portion 11 may be columnar. 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 the end opposite to the flange 13 side.

[0015] 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 may be provided. The bayonet 12 is used when mounting the vehicle lighting device 1, for example, to a housing 101 of a vehicle lamp 100 described later. The bayonet 12 may be used for a twist lock.

[0016] The flange 13 has a plate shape. The flange 13 has, for example, a substantially circular plate shape. A side surface of the flange 13 is located outward of the vehicle lighting device 1 from a side surface of the bayonet 12.

[0017] The heat dissipating fin 14 is provided on the side of the flange 13 opposite to the mounting portion 11. At least one heat dissipating fin 14 can be provided. For example, as shown in FIG. 1, the socket 10 can be provided with a plurality of heat dissipating fins 14. The plurality of heat dissipating fins 14 can be arranged side by side in a predetermined direction. The heat dissipating fin 14 has, for example, a plate or cylinder shape.

[0018] The connector holder 15 is provided on the opposite side of the flange 13 to the mounting portion 11. The connector holder 15 can be provided alongside the heat dissipation fins 14. The connector holder 15 has a cylindrical shape, and a connector 105 having a seal member 105a therein is inserted into the connector holder 15.

[0019] The socket 10 has a function of holding the light-emitting module 20 and the power supply unit 30, and a function of transferring heat generated in the light-emitting module 20 to the outside. Therefore, the socket 10 is preferably made of a material with high thermal conductivity. The socket 10 can be made of a metal such as an aluminum alloy, for example.

[0020] The socket 10 can also be made of, for example, a highly thermally conductive resin. The highly thermally conductive resin is, for example, a resin such as PET (Polyethylene terephthalate) or Nylon mixed with a filler using 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 efficiently dissipated. Also, the weight of the socket 10 can be reduced.

[0021] The power supply unit 30 includes, for example, a plurality of power supply terminals 31 and a holding unit 32 . The power supply terminals 31 may be rod-shaped. One end of each of the power supply terminals 31 protrudes from the bottom surface 11a1 of the recess 11a. One end of each of the power supply terminals 31 is soldered to the wiring pattern 21a provided on the substrate 21. The other end of each of the power supply terminals 31 is exposed inside the hole of the connector holder 15. The connector 105 is fitted to the power supply terminals 31 exposed inside the hole of the connector holder 15. The power supply terminals 31 are formed of a metal such as a copper alloy. The shape, arrangement, material, and the like of the power supply terminals 31 are not limited to those exemplified, and may be changed as appropriate.

[0022] When the socket 10 is formed using, for example, a highly thermally conductive resin containing a filler using carbon, or a metal, the socket 10 becomes conductive. Therefore, the holding portion 32 is provided to insulate the multiple power supply terminals 31 from the conductive socket 10. Note that when the socket 10 is formed using an insulating highly thermally conductive resin (for example, a highly thermally conductive resin containing a filler using aluminum oxide), the holding portion 32 can be omitted. For example, the holding portion 32 can be pressed into a hole provided in the socket 10 or adhered to the inner wall of the hole.

[0023] The heat transfer unit 40 is provided between the socket 10 and the light emitting module 20 (substrate 21). As shown in FIG. 1 and FIG. 2, the heat transfer unit 40 is provided, for example, inside the recess 11b that opens to the bottom surface 11a1 of the recess 11a. For example, the heat transfer unit 40 can be adhered to the inner wall of the recess 11b, attached inside the recess 11b via heat conductive grease (heat dissipation grease), or embedded inside the recess 11b by insert molding. The heat transfer unit 40 is formed from a material with high thermal conductivity. For example, the heat transfer unit 40 can be formed from a metal such as aluminum, an aluminum alloy, copper, or a copper alloy. Note that when the socket 10 is formed from a metal or when the heat generated in the light emitting module 20 is small, the heat transfer unit 40 can be omitted.

[0024] 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.

[0025] The substrate 21 is provided on one end side of the socket 10. The substrate 21 can be adhered, for example, onto the heat transfer section 40. In this case, the adhesive 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.

[0026] The substrate 21 has a plate shape. The planar shape of the substrate 21 (the shape when viewed from a direction along the central axis 1a of the vehicle lighting device 1) is, for example, substantially rectangular. The substrate 21 can be formed from, for example, an inorganic material such as ceramics (for example, aluminum oxide or aluminum nitride), or an organic material 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 covered with an insulating material. The substrate 21 may also have a single-layer structure or a multi-layer structure.

[0027] Moreover, a wiring pattern 21a is provided on the surface of the substrate 21. The wiring pattern 21a is formed from, for example, a material containing silver as a main component or a material containing copper as a main component.

[0028] The light-emitting element 22 is provided on the substrate 21 (the surface 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 vehicle lighting device 1 (light-emitting module 20) illustrated in Figs. 1 and 2 is provided with a plurality of light-emitting elements 22. When a plurality of light-emitting elements 22 are provided, the plurality of light-emitting elements 22 can be connected in series.

[0029] The light emitting elements 22 may be, for example, light emitting diodes, organic light emitting diodes, laser diodes, or the like. The light emitting element 22 may be a chip-shaped light emitting element, a surface mount type light emitting element such as a PLCC (Plastic Leaded Chip Carrier) type, or a light emitting element having a lead wire such as a bullet type. The light emitting element 22 illustrated in FIG. 2 is a chip-shaped light emitting element. In this case, in consideration of miniaturization of the light emitting module 20 and thus miniaturization of the vehicle lighting device 1, it is preferable to use a chip-shaped light emitting element. In the following, as an example, a case where the light emitting element 22 is a chip-shaped light emitting element will be described.

[0030] The chip-shaped light-emitting element 22 can be mounted on the wiring pattern 21a by COB (Chip On Board). The chip-shaped light-emitting element 22 may be any of an upper electrode type light-emitting element, a top and bottom electrode type light-emitting element, and a flip chip type light-emitting element.

[0031] 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 is formed, for example, from a thermoplastic resin. The frame portion 23 can have a function of defining the formation range of the sealing portion 24 and a function of a reflector. The frame portion 23 can be omitted. In the case where the frame portion 23 is omitted, for example, a dome-shaped sealing portion 24 is provided on the substrate 21.

[0032] The sealing portion 24 is provided inside the frame portion 23. The sealing portion 24 is provided so as to cover the area surrounded 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 resin having light-transmitting properties. The resin is, for example, a silicone resin. The sealing portion 24 may also contain a phosphor.

[0033] In addition, optical elements and the like can be provided as necessary. Examples of the optical elements include a convex lens, a concave lens, a light guide, etc. The optical elements can be provided on the sealing portion 24, for example.

[0034] The circuit element 25 can be a passive element or an active element used to configure the light-emitting circuit 20a having the light-emitting element 22. The circuit element 25 is provided on the substrate 21. The circuit element 25 is provided, for example, on the periphery of the frame portion 23 and is electrically connected to the wiring pattern 21a. The circuit element 25 is electrically connected to the light-emitting element 22 via the wiring pattern 21a.

[0035] FIG. 3 is a circuit diagram illustrating the light emission circuit 20a. As shown in Fig. 3, the light-emitting circuit 20a has, for example, a light-emitting element 22 and a circuit element 25. The circuit element 25 can be, for example, a resistor 25a, a protective element 25b, a control element 25c, a negative characteristic thermistor 25d (corresponding to an example of a first negative characteristic thermistor), a resistor 25e, and a positive characteristic thermistor 25f (corresponding to an example of a second positive characteristic thermistor). However, the circuit element 25 provided in the light-emitting circuit 20a is not limited to the exemplified ones. For example, the light-emitting circuit 20a can further have a capacitor, a negative characteristic thermistor, an inductor, a surge absorber, a varistor, an integrated circuit, a computing element, and the like, in addition to the above-mentioned ones.

[0036] 1 and 2, the resistor 25a may be, for example, a surface mount resistor, a resistor having leads (metal oxide film resistor), a film resistor formed by using a screen printing method, etc. The resistor 25a illustrated in FIG. 1 is a surface mount resistor.

[0037] Here, since there is variation in the forward voltage characteristics of the light-emitting element 22, 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 irradiated from the light-emitting element 22. Therefore, in order to keep the brightness of the light irradiated from the light-emitting element 22 within a predetermined range, the value of the current flowing through the light-emitting element 22 is controlled to be within a predetermined range by the resistor 25a connected in series to the light-emitting element 22. In this case, the resistance value of the resistor 25a is changed to keep the value of the current flowing through the light-emitting element 22 within the predetermined range.

[0038] When the resistor 25a is a surface mount resistor or a resistor with leads, the resistor 25a is selected to have an appropriate resistance value according to the forward voltage characteristics of the light emitting element 22. When the resistor 25a is a film resistor, the resistance value can be increased by removing a part of the resistor 25a. For example, a part of the film resistor can be easily removed by irradiating the film resistor with laser light. The number, arrangement, size, etc. of the resistors 25a are not limited to those exemplified, and can be appropriately changed according to the number and specifications of the light emitting elements 22.

[0039] The protective element 25b is provided, for example, to prevent a reverse voltage from being applied to the light-emitting element 22 and to prevent pulse noise from the reverse direction from being applied to the light-emitting element 22. The protective element 25b is, for example, a diode. The protective element 25b illustrated in FIG. 1 is a surface-mounted diode.

[0040] The control element 25c controls the current (output current Ia) flowing through the light-emitting element 22 in accordance with the ambient temperature of the light-emitting element 22. For example, the control element 25c can be an integrated circuit capable of performing temperature derating.

[0041] As shown in FIG. 3, the control element 25c has a VIN terminal, an OUT terminal, an RTH terminal (corresponding to an example of the first input side), an ISET terminal (corresponding to an example of the second input side), and a GND terminal. The VIN terminal is electrically connected to a battery mounted on the vehicle, for example, via a protection element 25b. The OUT terminal is electrically connected to the light emitting element 22, for example, via a resistor 25a. In this case, the anode of the light emitting element 22 is electrically connected to the OUT terminal. The cathode of the light emitting element 22 is electrically connected to the ground of the vehicle, such as the chassis of the vehicle body. The ISET terminal is electrically connected to, for example, a resistor 25e and a positive characteristic thermistor 25f connected in series (corresponding to an example of the second circuit). The RTH terminal is electrically connected to a negative characteristic thermistor 25d (corresponding to an example of the first circuit). The GND terminal is electrically connected to, for example, the ground of the vehicle.

[0042] Furthermore, the control element 25c includes, for example, a current driver 25c1, a current setting circuit 25c2, and a constant current circuit 25c3. The input side of the current driver 25c1 is electrically connected to the VIN terminal. The output side of the current driver 25c1 is electrically connected to the light-emitting element 22 via the OUT terminal. The current driver 25c1 generates a current (output current Ia) to be passed through the light-emitting element 22. The current driver 25c1 performs constant current control on the output current Ia so that the output current Ia becomes a predetermined value. The current driver 25c1 has a constant current circuit including, for example, an output transistor, a sense resistor, and an error amplifier. The target value of the output current Ia is set based on the set current Ib from the current setting circuit 25c2.

[0043] One input side of the current setting circuit 25c2 is electrically connected to the negative characteristic thermistor 25d via the RTH terminal. The other input side of the current setting circuit 25c2 is electrically connected to the resistor 25e and the positive characteristic thermistor 25f via the ISET terminal. The output side of the current setting circuit 25c2 is electrically connected to the current driver 25c1. The current setting circuit 25c2 generates a set current Ib for setting a target value of the output current Ia. The set current Ib is generated based on a change in the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal. When the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases, the current setting circuit 25c2 adjusts to decrease the output current Ia. Moreover, the current setting circuit 25c2 adjusts the set current Ib based on the terminal voltage generated at the ISET terminal. When the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the PTC thermistor 25f increases, the current setting circuit 25c2 performs adjustment to increase the rate at which the output current Ia is reduced.

[0044] The constant current circuit 25c3 is electrically connected between the input side of the current setting circuit 25c2 and the RTH terminal. The constant current circuit 25c3 passes a predetermined current through the negative characteristic thermistor 25d via the RTH terminal. Therefore, a terminal voltage based on the change in the resistance value of the negative characteristic thermistor 25d is generated in the RTH terminal.

[0045] The resistance value of the negative temperature coefficient thermistor 25d decreases when a predetermined temperature (Curie temperature) is exceeded. Furthermore, the resistance value of the positive characteristic thermistor 25f increases when the temperature exceeds a predetermined temperature (Curie temperature). In this case, for example, the Curie temperature of the positive characteristic thermistor 25f is higher than the Curie temperature of the negative characteristic thermistor 25d. The negative characteristic thermistor 25d and the positive characteristic thermistor 25f may be, for example, surface-mount type thermistors. The resistor 25e may be, for example, any of a surface mount resistor, a resistor having leads (metal oxide film resistor), and a film resistor formed by using a screen printing method, etc. The resistor 25e illustrated in FIG. 1 is a surface mount resistor.

[0046] As described later, the current setting circuit 25c2 generates a set current Ib based on the resistance value of a negative characteristic thermistor 25d electrically connected to the RTH terminal, for setting the output current Ia that the current driver 25c1 passes through the light emitting element 22. The current setting circuit 25c2 also adjusts the set current Ib based on the resistance value of a positive characteristic thermistor 25f electrically connected to the ISET terminal.

[0047] Here, a light emission circuit 120a according to a comparative example will be described. FIG. 4 is a circuit diagram illustrating a light-emitting circuit 120a according to a comparative example. 4, the light-emitting circuit 120a includes a light-emitting element 22, a resistor 25a, a protective element 25b, a control element 25c, a negative temperature coefficient thermistor 25d, and a resistor 25e. That is, the light-emitting circuit 120a does not include the positive temperature coefficient thermistor 25f that is provided in the light-emitting circuit 20a.

[0048] 5 and 6 are graphs illustrating the effects of the light-emitting circuit 120a according to the comparative example. 5 and 6, "La" is the total luminous flux (e.g., 350 lumens) required when the ambient temperature of the light-emitting element 22 is 20° C. "Lb" is the total luminous flux (e.g., 280 lumens) required when the ambient temperature of the light-emitting element 22 is 60° C.

[0049] 5, the light-emitting circuit 120a is also provided with a control element 25c, so that the current flowing through the light-emitting element 22 can be controlled in accordance with the ambient temperature of the light-emitting element 22. That is, temperature derating is also performed in the light-emitting circuit 120a.

[0050] In this case, the current setting circuit 25c2 generates the set current Ib based on the change in the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal. The current setting circuit 25c2 also adjusts the set current Ib based on the terminal voltage generated at the ISET terminal. Since only the resistor 25e is connected to the ISET terminal, a terminal voltage according to the resistance value of the resistor 25e is generated. Moreover, the current driver 25c1 sets a target value of the output current Ia based on the set current Ib from the current setting circuit 25c2.

[0051] When the temperature of the negative characteristic thermistor 25d is equal to or lower than the Curie temperature of the negative characteristic thermistor 25d (for example, the ambient temperature of the light emitting element 22 is equal to or lower than 40°C), there is almost no change in the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal. Therefore, there is almost no change in the set current Ib generated by the current setting circuit 25c2 based on the resistance value of the negative characteristic thermistor 25d. In this case, for example, the resistance value of the resistor 25e electrically connected to the ISET terminal is set so that the output current Ia that satisfies the total luminous flux La required when the temperature is 20°C is output from the current driver 25c1. In this case, for example, when the resistance value of the resistor 25e electrically connected to the ISET terminal is decreased, the output current Ia increases. Also, when the resistance value of the resistor 25e electrically connected to the ISET terminal is increased, the output current Ia decreases.

[0052] When the temperature of the negative characteristic thermistor 25d exceeds the Curie temperature of the negative characteristic thermistor 25d (for example, when the ambient temperature of the light emitting element 22 exceeds 40°C), the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases. Therefore, the current setting circuit 25c2 generates the set current Ib based on the change in the resistance value of the negative characteristic thermistor 25d. In this case, when the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases, the output current Ia decreases.

[0053] In this case, as shown in FIG. 5, there may be cases where the required total luminous flux Lb cannot be satisfied when the ambient temperature of the light emitting element 22 reaches a predetermined temperature (for example, 60° C.).

[0054] In this case, the set current Ib, and therefore the output current Ia, can be adjusted by the resistance value of the resistor 25e electrically connected to the ISET terminal. Therefore, by selecting a resistor 25e having an appropriate resistance value electrically connected to the ISET terminal or by changing the resistance value of the resistor 25e, it is possible to satisfy the total luminous flux Lb required at a predetermined temperature (e.g., 60°C) as shown in Fig. 6. For example, by decreasing the resistance value of the resistor 25e electrically connected to the ISET terminal, an adjustment can be made to increase the output current Ia.

[0055] However, if this is done, when the ambient temperature of the light-emitting element 22 becomes higher (for example, at 80° C.), the decrease in the total luminous flux (decrease in the output current Ia flowing through the light-emitting element 22) becomes too small. Therefore, the temperature of the light-emitting element 22 becomes too high, and there is a risk that the temperature of the light-emitting element 22 will exceed the maximum junction temperature.

[0056] Therefore, in the light emission circuit 20a according to the present embodiment, a PTC thermistor 25f connected in series with a resistor 25e is further electrically connected to the ISET terminal of the control element 25c.

[0057] If the positive characteristic thermistor 25f is provided, a terminal voltage is generated at the RTH terminal based on a change in the ambient temperature of the light-emitting element 22. Therefore, based on a change in the ambient temperature of the light-emitting element 22, the set current Ib, and therefore the output current Ia, can be changed.

[0058] In this case, when the temperature of PTC thermistor 25f is equal to or lower than the Curie temperature of PTC thermistor 25f (for example, when the ambient temperature of light-emitting element 22 is equal to or lower than 60° C.), the resistance value of PTC thermistor 25f hardly changes. When the ambient temperature of light-emitting element 22 is close to the Curie temperature of PTC thermistor 25f, the amount of change in the resistance value is small. As the temperature of the PTC thermistor 25f rises above the Curie temperature of the PTC thermistor 25f (for example, as the ambient temperature of the light emitting element 22 rises above 60° C.), the resistance value of the PTC thermistor 25f increases rapidly.

[0059] FIG. 7 is a graph illustrating the effects of the light-emitting circuit 20a according to the present embodiment. In a region where the temperature of the NTC thermistor 25d is equal to or lower than the Curie temperature of the NTC thermistor 25d and the temperature of the PTC thermistor 25f is equal to or lower than the Curie temperature of the PTC thermistor 25f (for example, a temperature region where the ambient temperature of the light-emitting element 22 is equal to or lower than 40° C.), the set current Ib is set based on the resistance value of the resistor 25e electrically connected to the ISET terminal. Therefore, as shown in FIG. 7, the total luminous flux of the light irradiated from the light-emitting element 22 hardly changes.

[0060] In a region where the temperature of the negative characteristic thermistor 25d exceeds the Curie temperature of the negative characteristic thermistor 25d and the temperature of the positive characteristic thermistor 25f is equal to or lower than the Curie temperature of the positive characteristic thermistor 25f (for example, a temperature region where the ambient temperature of the light-emitting element 22 exceeds 40°C (corresponding to an example of the first temperature) and is equal to or lower than 60°C (corresponding to an example of the second temperature)), the set current Ib is set based on a decrease in the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal. When the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases, the output current Ia decreases. Therefore, as shown in FIG. 7, the total luminous flux of the light irradiated from the light-emitting element 22 decreases in response to an increase in temperature. That is, the output current Ia decreases due to temperature derating, and therefore the total luminous flux of the light irradiated from the light-emitting element 22 decreases.

[0061] Furthermore, in a region where the temperature of the NTC thermistor 25d exceeds the Curie temperature of the NTC thermistor 25d and the temperature of the PTC thermistor 25f exceeds the Curie temperature of the PTC thermistor 25f (for example, a temperature region where the ambient temperature of the light-emitting element 22 exceeds 60°C), the set current Ib is adjusted according to an increase in the resistance value of the PTC thermistor 25f electrically connected to the ISET terminal, and the rate at which the output current Ia decreases increases. When the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the PTC thermistor 25f increases with an increase in the resistance value of the PTC thermistor 25f, the output current Ia further decreases. As a result, as shown in FIG. 7, the rate at which the total luminous flux decreases can be increased. That is, in an area where the ambient temperature of the light emitting element 22 is high, the rate at which the total luminous flux is reduced can be changed.

[0062] In this case, for example, if the total luminous flux Lb required when the ambient temperature of the light-emitting element 22 is 60° C. is specified, it is preferable to measure the temperature (e.g., 120° C.±10° C.) of the PTC thermistor 25f when the ambient temperature of the light-emitting element 22 is 60° C., and select the PTC thermistor 25f whose Curie temperature is the measured temperature (e.g., 120° C.±10° C.). In this way, in an area where the ambient temperature of the light-emitting element 22 is high, the required total luminous flux can be obtained, and the temperature rise of the light-emitting element 22 can be suppressed.

[0063] As described above, the current setting circuit 25c2 generates the set current Ib that reduces the output current Ia when the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases. When the resistance value of the positive characteristic thermistor 25f electrically connected to the ISET terminal increases, the current setting circuit 25c2 adjusts the set current Ib to increase the rate at which the output current Ia decreases.

[0064] Here, the total luminous flux of the light emitted from the light emitting element 22 may decrease when the temperature of the light emitting element 22 increases. FIG. 8 is a graph illustrating another action and effect of the light-emitting circuit 120a according to the comparative example. When the ambient temperature of the light emitting element 22 is low (for example, below 40° C.), there is almost no change in the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal.

[0065] Therefore, as shown in FIG. 8, in a region where the ambient temperature of the light emitting element 22 is low (for example, a region below 40° C.), the total luminous flux may decrease with an increase in the ambient temperature of the light emitting element 22.

[0066] FIG. 9 is a circuit diagram illustrating a light emission circuit 20b according to another embodiment. FIG. 10 is a graph illustrating the effects of the light-emitting circuit 20b. 9, the light-emitting circuit 20b includes, for example, a light-emitting element 22, a resistor 25a, a protective element 25b, a control element 25c, a negative characteristic thermistor 25d, a resistor 25e, a positive characteristic thermistor 25f, and a negative characteristic thermistor 25g (corresponding to an example of a second negative characteristic thermistor). In other words, the light-emitting circuit 20b can be configured by further adding a negative characteristic thermistor 25g to the light-emitting circuit 20a described above.

[0067] The negative characteristic thermistor 25g can be connected in series with the positive characteristic thermistor 25f and resistor 25e, which are also connected in series. The series-connected positive characteristic thermistor 25f, resistor 25e, and negative characteristic thermistor 25g are electrically connected to the ISET terminal (corresponding to an example of a second circuit). The negative characteristic thermistor 25d is electrically connected to the RTH terminal (corresponding to an example of a first circuit).

[0068] In a region where the ambient temperature of the light-emitting element 22 is low (for example, a region below 40° C.), the temperature of the positive characteristic thermistor 25f is below the Curie temperature of the positive characteristic thermistor 25f, and the resistance value of the positive characteristic thermistor 25f is approximately constant. Therefore, in a region where the ambient temperature of the light-emitting element 22 is low, the set current Ib, and therefore the output current Ia, change based on the change in the resistance value of the negative characteristic thermistor 25g electrically connected to the ISET terminal.

[0069] The resistance value of the negative characteristic thermistor 25g electrically connected to the ISET terminal decreases as the temperature increases, so that in areas where the ambient temperature of the light-emitting element 22 is low, when the ambient temperature of the light-emitting element 22 increases, the resistance value of the negative characteristic thermistor 25g decreases.

[0070] When the combined resistance value of the resistor 25e electrically connected to the ISET terminal, the positive characteristic thermistor 25f, and the negative characteristic thermistor 25g decreases with the decrease in the resistance value of the negative characteristic thermistor 25g, the output current Ia increases. Therefore, as shown in FIG. 10, in a region where the ambient temperature of the light-emitting element 22 is low, the set current Ib and therefore the output current Ia can be increased with the increase in the ambient temperature of the light-emitting element 22. That is, in a region where the ambient temperature of the light-emitting element 22 is low, the decrease in the total luminous flux associated with the increase in the ambient temperature of the light-emitting element 22 can be offset by the increase in the total luminous flux due to the increase in the output current Ia. As a result, for example, as shown in FIG. 7, in a region where the ambient temperature of the light-emitting element 22 is low, the fluctuation of the total luminous flux can be suppressed. As described above, in the temperature region below the Curie temperature of the positive characteristic thermistor 25f, the current setting circuit 25c2 generates a setting current Ib that increases the output current Ia based on a decrease in the resistance value of the negative characteristic thermistor 25g electrically connected to the ISET terminal.

[0071] FIG. 11 is a circuit diagram illustrating a light emission circuit 20c according to another embodiment. 11, the light-emitting circuit 20c includes, for example, a light-emitting element 22, a resistor 25a, a protective element 25b, a control element 25c, a negative characteristic thermistor 25d, a resistor 25e, and a positive characteristic thermistor 25f. That is, the light-emitting circuit 20c is obtained by switching the connection positions of the negative characteristic thermistor 25d and the positive characteristic thermistor 25f in the light-emitting circuit 20a described above. In this case, for example, a resistor 25e and a negative characteristic thermistor 25d connected in series are electrically connected to the ISET terminal (corresponding to an example of a second circuit), and a positive characteristic thermistor 25f is electrically connected to the RTH terminal (corresponding to an example of a first circuit).

[0072] In this case, the current setting circuit 25c2 generates a set current Ib based on the resistance value of the positive characteristic thermistor 25f electrically connected to the RTH terminal to set the output current Ia that the current driver 25c1 passes through the light emitting element 22. The current setting circuit 25c2 also adjusts the set current Ib based on the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the negative characteristic thermistor 25d.

[0073] Here, the current setting circuit 25c2 of the light-emitting circuit 20c has settings different from the operation of the current setting circuit 25c2 of the light-emitting circuit 20a described above. The current setting circuit 25c2 performs an adjustment to decrease the output current Ia when the resistance value of the positive temperature coefficient thermistor 25f electrically connected to the RTH terminal increases. When the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the negative characteristic thermistor 25d decreases, the current setting circuit 25c2 performs an adjustment to increase the rate at which the output current Ia is reduced.

[0074] If the positive characteristic thermistor 25f is provided, a terminal voltage is generated at the RTH terminal based on a change in the ambient temperature of the light-emitting element 22. Therefore, based on a change in the ambient temperature of the light-emitting element 22, the set current Ib, and therefore the output current Ia, can be changed.

[0075] In this case, when the temperature of PTC thermistor 25f is equal to or lower than the Curie temperature of PTC thermistor 25f (for example, when the ambient temperature of light-emitting element 22 is equal to or lower than 40° C.), the resistance value of PTC thermistor 25f hardly changes. When the ambient temperature of light-emitting element 22 is close to the Curie temperature of PTC thermistor 25f, the amount of change in the resistance value is small. As the temperature of the PTC thermistor 25f rises above the Curie temperature of the PTC thermistor 25f (for example, as the ambient temperature of the light emitting element 22 rises above 40° C.), the resistance value of the PTC thermistor 25f increases rapidly. Therefore, the current setting circuit 25c2 generates a set current Ib for reducing the output current Ia based on an increase in the resistance value of the PTC thermistor 25f.

[0076] Furthermore, if the ambient temperature of the light-emitting element 22 becomes higher (for example, if the ambient temperature of the light-emitting element 22 becomes higher than 60°C), the resistance value of the negative characteristic thermistor 25d electrically connected to the ISET terminal decreases, and the current setting circuit 25c2 increases the rate at which the output current Ia is reduced based on the amount of decrease in the resistance value of the negative characteristic thermistor 25d. As described above, the configuration of the light-emitting circuit 20c can also provide the same effects as those of the light-emitting circuit 20a described above.

[0077] FIG. 12 is a circuit diagram illustrating a light emitting circuit 20d according to another embodiment. 12, the light-emitting circuit 20d includes, for example, a light-emitting element 22, a resistor 25a, a protective element 25b, a control element 25c, a negative characteristic thermistor 25d, and a resistor 25e. That is, the light-emitting circuit 20d is configured such that the positive characteristic thermistor 25f in the light-emitting circuit 20a described above is replaced with a negative characteristic thermistor 25d. In this case, for example, a resistor 25e and a negative characteristic thermistor 25d connected in series are electrically connected to the ISET terminal (corresponding to an example of a second circuit). A negative characteristic thermistor 25d is electrically connected to the RTH terminal (corresponding to an example of a first circuit).

[0078] In this case, the current setting circuit 25c2 generates a set current Ib based on the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal to set the output current Ia that the current driver 25c1 passes through the light emitting element 22. The current setting circuit 25c2 also adjusts the set current Ib based on the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the negative characteristic thermistor 25d.

[0079] Here, the current setting circuit 25c2 of the light-emitting circuit 20d has settings different from the operation of the current setting circuit 25c2 of the light-emitting circuit 20a described above. When the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases, the current setting circuit 25c2 performs an adjustment to decrease the output current Ia. When the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the negative characteristic thermistor 25d decreases, the current setting circuit 25c2 performs an adjustment to increase the rate at which the output current Ia is reduced.

[0080] Therefore, similarly to the case of the light-emitting circuit 20a described above, the current setting circuit 25c2 can change the set current Ib, and therefore the output current Ia, based on the change in the ambient temperature of the light-emitting element 22. Also, similarly to the case of the light-emitting circuit 20c described above, the set current Ib can be adjusted. As described above, the configuration of the light-emitting circuit 20d can also provide the same effects as those of the light-emitting circuit 20a described above.

[0081] FIG. 13 is a circuit diagram illustrating a light emission circuit 20e according to another embodiment. 13, the light-emitting circuit 20e includes, for example, a light-emitting element 22, a resistor 25a, a protective element 25b, a control element 25c, a positive characteristic thermistor 25f, and a resistor 25e. That is, the light-emitting circuit 20d is configured such that the negative characteristic thermistor 25d in the light-emitting circuit 20a described above is replaced with a positive characteristic thermistor 25f. In this case, for example, a resistor 25e and a positive temperature coefficient thermistor 25f connected in series are electrically connected to the ISET terminal (corresponding to an example of a second circuit). A positive temperature coefficient thermistor 25f is electrically connected to the RTH terminal (corresponding to an example of a first circuit).

[0082] In this case, the current setting circuit 25c2 generates a set current Ib based on the resistance value of the positive characteristic thermistor 25f electrically connected to the RTH terminal to set the output current Ia that the current driver 25c1 passes through the light emitting element 22. The current setting circuit 25c2 also adjusts the set current Ib based on the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the positive characteristic thermistor 25f.

[0083] Here, the current setting circuit 25c2 of the light emission circuit 20e has a different setting from the operation of the current setting circuit 25c2 of the light emission circuit 20a described above. The current setting circuit 25c2 performs an adjustment to decrease the output current Ia when the resistance value of the positive temperature coefficient thermistor 25f electrically connected to the RTH terminal increases. The current setting circuit 25c2 performs an adjustment such that, when a combined resistance value of the resistor 25e electrically connected to the ISET terminal and the PTC thermistor 25f increases, the rate at which the output current Ia is reduced increases.

[0084] Therefore, similarly to the case of the light-emitting circuit 20c described above, the current setting circuit 25c2 can change the set current Ib, and therefore the output current Ia, based on the change in the ambient temperature of the light-emitting element 22. Also, similarly to the case of the light-emitting circuit 20a described above, the set current Ib can be adjusted. As described above, the configuration of the light-emitting circuit 20e can also provide the same effects as those of the light-emitting circuit 20a described above.

[0085] FIG. 14 is a circuit diagram illustrating a light emission circuit 20f according to another embodiment. 14, the light-emitting circuit 20f includes, for example, a light-emitting element 22, a resistor 25a, a protective element 25b, a control element 25c, a negative characteristic thermistor 25d, a resistor 25e, a positive characteristic thermistor 25f, and a positive characteristic thermistor 25h (corresponding to an example of a first positive characteristic thermistor). That is, the light-emitting circuit 20f is obtained by switching the connection positions of the positive characteristic thermistor 25f and the negative characteristic thermistor 25d in the light-emitting circuit 20c described above, and further by connecting the positive characteristic thermistor 25h in series with the negative characteristic thermistor 25d.

[0086] In this case, the series-connected PTC thermistor 25h and NTC thermistor 25d are electrically connected to the RTH terminal (corresponding to an example of a first circuit). The series-connected resistor 25e and PTC thermistor 25f are electrically connected to the ISET terminal (corresponding to an example of a second circuit).

[0087] Here, the current setting circuit 25c2 of the light-emitting circuit 20f is set in the same manner as the current setting circuit 25c2 of the light-emitting circuit 20a and the current setting circuit 25c2 of the light-emitting circuit 20c described above. The current setting circuit 25c2 performs an adjustment to decrease the output current Ia when the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases. The current setting circuit 25c2 performs an adjustment such that, when a combined resistance value of the resistor 25e electrically connected to the ISET terminal and the PTC thermistor 25f increases, the rate at which the output current Ia is reduced increases.

[0088] In the region where the ambient temperature of the light-emitting element 22 is low (for example, a region below 40°C), the temperature of the positive characteristic thermistor 25f electrically connected to the ISET terminal is below the Curie temperature of the positive characteristic thermistor 25f, and therefore the combined resistance value of resistor 25e and the positive characteristic thermistor 25f is approximately constant. Therefore, in a region where the ambient temperature of the light-emitting element 22 is low, the set current Ib and therefore the output current Ia change based on the change in the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d electrically connected to the RTH terminal.

[0089] The Curie temperature of the positive characteristic thermistor 25h electrically connected to the RTH terminal and the Curie temperature of the negative characteristic thermistor 25d are adjusted so that in a region where the ambient temperature of the light-emitting element 22 is low (e.g., a region below 40°C), the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d increases as the temperature rises, and when the temperature rises further (e.g., in a region exceeding 40°C), the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d begins to decrease.

[0090] In a region where the ambient temperature of the light-emitting element 22 is low (for example, a region below 40° C.), when the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d electrically connected to the RTH terminal increases with an increase in the resistance value of the positive characteristic thermistor 25h, the output current Ia increases. Therefore, as shown in FIG. 10, in a region where the ambient temperature of the light-emitting element 22 is low, the set current Ib and therefore the output current Ia can be increased with an increase in the ambient temperature of the light-emitting element 22. That is, in a region where the ambient temperature of the light-emitting element 22 is low, the decrease in the total luminous flux associated with an increase in the ambient temperature of the light-emitting element 22 can be offset by the increase in the total luminous flux due to the increase in the output current Ia. As a result, for example, as shown in FIG. 7, in a region where the ambient temperature of the light-emitting element 22 is low, the fluctuation of the total luminous flux can be suppressed.

[0091] Furthermore, when the ambient temperature of the light-emitting element 22 rises and the rate of decrease in the resistance value of the negative characteristic thermistor 25d becomes greater than the rate of increase in the resistance value of the positive characteristic thermistor 25h (for example, when it exceeds 40°C), the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d electrically connected to the RTH terminal changes from increasing to decreasing, so that the set current Ib and ultimately the output current Ia decrease.

[0092] Furthermore, in a region where the temperature of the PTC thermistor 25f electrically connected to the ISET terminal exceeds the Curie temperature of the PTC thermistor 25f (for example, a temperature region where the ambient temperature of the light-emitting element 22 exceeds 60°C), the set current Ib is adjusted in accordance with an increase in the resistance value of the PTC thermistor 25f electrically connected to the ISET terminal, and the rate at which the output current Ia decreases increases. If the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the PTC thermistor 25f increases with an increase in the resistance value of the PTC thermistor 25f, the output current Ia further decreases. As a result, as shown in FIG. 10, the rate at which the output current Ia decreases can be increased. That is, in an area where the ambient temperature of the light emitting element 22 is high, the rate at which the total luminous flux is reduced can be changed.

[0093] As described above, the configuration of the light-emitting circuit 20f can also provide the same effects as those of the light-emitting circuit 20c described above.

[0094] (Vehicle lighting fixtures) In one embodiment of the present invention, a vehicle lamp 100 can be provided that includes the vehicle lighting device 1. The above-mentioned description of the vehicle lighting device 1 and modified examples of the vehicle lighting device 1 (for example, the light-emitting circuit 20b, or a device in which a person skilled in the art appropriately adds, deletes, or modifies components and has the features of the present invention) can all be applied to the vehicle lamp 100.

[0095] In the following, as an example, a case where the vehicular lamp 100 is a front combination light installed in an automobile will be described. However, the vehicular lamp 100 is not limited to a front combination light installed in an automobile. The vehicular lamp 100 may be any vehicular lamp that is installed in an automobile, a railroad car, or the like.

[0096] FIG. 15 is a schematic partial cross-sectional view illustrating the vehicle lamp 100. As shown in FIG. As shown in FIG. 15, a vehicle lamp 100 includes, for example, a vehicle lighting device 1, a housing 101, a cover 102, an optical element 103, a seal member 104, and a connector 105.

[0097] The vehicle lighting device 1 is attached to the housing 101. The housing 101 holds the mounting portion 11. The housing 101 is box-shaped with one end side open. The housing 101 is formed of, for example, a resin that does not transmit light. The bottom surface of the housing 101 is provided with a mounting hole 101a into which the portion of the mounting portion 11 provided with the bayonet 12 is inserted. A recess is provided around the mounting hole 101a into which the bayonet 12 provided on the mounting portion 11 is inserted. Note that, although the case where the mounting hole 101a is directly provided in the housing 101 has been exemplified, a mounting member having the mounting hole 101a may be provided on the housing 101.

[0098] When mounting the vehicle lighting device 1 to the vehicle lamp 100, the portion of the mounting portion 11 on which the bayonet 12 is provided is inserted into the mounting hole 101a, and the vehicle lighting device 1 is rotated. Then, for example, the bayonet 12 is held in a fitting portion provided on the periphery of the mounting hole 101a. This type of mounting method is called a twist lock.

[0099] The cover 102 is provided so as to cover 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 a function such as a lens.

[0100] Light emitted from the vehicle lighting device 1 is incident on the optical element 103. The optical element 103 reflects, diffuses, guides, and collects the light emitted from the vehicle lighting device 1, and forms a predetermined light distribution pattern. For example, the optical element 103 illustrated in Fig. 15 is a reflector. In this case, the optical element 103 reflects the light emitted from the vehicle lighting device 1 to form a predetermined light distribution pattern.

[0101] The seal member 104 is provided between the flange 13 and the housing 101. The seal member 104 has an annular shape and is made of an elastic material such as rubber or silicone resin.

[0102] When the vehicle lighting device 1 is attached to the vehicle lamp 100, the seal member 104 is sandwiched between the flange 13 and the housing 101. Therefore, the seal member 104 can seal the internal space of the housing 101. In addition, the bayonet 12 is pressed against the housing 101 by the elastic force of the seal member 104. Therefore, it is possible to prevent the vehicle lighting device 1 from coming off the housing 101.

[0103] The connector 105 is fitted to ends of the multiple power supply terminals 31 exposed inside the connector holder 15. A lighting circuit and the like are electrically connected to the connector 105. Therefore, by fitting the connector 105 to ends of the multiple power supply terminals 31, the lighting circuit and the like can be electrically connected to the light-emitting element 22.

[0104] Furthermore, a seal member 105a is provided on the connector 105. When the connector 105 having the seal member 105a is inserted into the inside of the connector holder 15, the inside of the connector holder 15 is sealed so as to be watertight.

[0105] Although some embodiments of the present invention have been illustrated above, these embodiments are presented as examples 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, modifications, etc. can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims. In addition, the above-mentioned embodiments can be implemented in combination with each other.

[0106] Below, additional notes regarding the above-described embodiment are given.

[0107] (Appendix 1) Socket and; A substrate provided on one end side of the socket; A light emitting element provided on the substrate; a control element provided on the substrate, the control element having a current driver having an output side electrically connected to the light emitting element, and a current setting circuit having an output side electrically connected to the current driver; a first circuit provided on the substrate, electrically connected to a first input side of the current setting circuit, and having a resistance value that changes depending on an ambient temperature of the light emitting element; a second circuit provided on the substrate, electrically connected to a second input side of the current setting circuit, and having a resistance value that changes depending on the ambient temperature of the light emitting element; Equipped with The current setting circuit includes: In a temperature range in which the ambient temperature of the light-emitting element exceeds a first temperature and is equal to or lower than a second temperature higher than the first temperature, an output current flowing through the light-emitting element is reduced in accordance with an increase in the ambient temperature of the light-emitting element based on a change in the resistance value of the first circuit; A vehicle lighting device that, in a temperature region where the ambient temperature of the light-emitting element exceeds the second temperature, increases the rate at which the output current flowing to the light-emitting element is reduced as the ambient temperature of the light-emitting element rises, based on a change in the resistance value of the second circuit.

[0108] (Appendix 2) The vehicle lighting device described in Appendix 1, wherein the current setting circuit increases the output current flowing to the light-emitting element as the ambient temperature of the light-emitting element rises based on a change in the resistance value of the second circuit in a temperature region where the ambient temperature of the light-emitting element is lower than the first temperature.

[0109] (Appendix 3) The vehicle lighting device described in Appendix 1 or 2, wherein the current setting circuit increases the output current flowing to the light-emitting element as the ambient temperature of the light-emitting element rises based on a change in the resistance value of the first circuit in a temperature region where the ambient temperature of the light-emitting element is lower than the first temperature.

[0110] (Appendix 4) the first circuit has a first NTC thermistor or a first PTC thermistor, or the first NTC thermistor and the first PTC thermistor connected in series; The vehicle lighting device according to any one of Appendices 1 to 3, wherein the second circuit has a second negative characteristic thermistor, or a second positive characteristic thermistor, or the second negative characteristic thermistor and the second positive characteristic thermistor connected in series.

[0111] (Appendix 5) The vehicle lighting device described in Appendix 4, wherein the current setting circuit generates a set current for setting the output current that the current driver passes through the light-emitting element based on the resistance value of the first negative characteristic thermistor, and adjusts the set current based on the resistance value of the second positive characteristic thermistor.

[0112] (Appendix 6) A vehicle lighting device as described in Appendix 5, wherein the current setting circuit generates the set current such that the output current decreases when the resistance value of the first negative characteristic thermistor decreases, and adjusts the set current to increase the rate at which the output current decreases when the resistance value of the second positive characteristic thermistor increases.

[0113] (Appendix 7) In a temperature region equal to or lower than the Curie temperature of the second positive temperature coefficient thermistor, 7. The vehicle lighting device according to claim 4, wherein the current setting circuit generates the set current that increases the output current based on a decrease in a resistance value of the second negative characteristic thermistor.

[0114] (Appendix 8) A vehicle lighting device according to any one of appendixes 1 to 7; A housing in which the vehicle lighting device is mounted; A vehicle lamp equipped with: [Explanation of symbols]

[0115] REFERENCE SIGNS LIST 1 vehicle lighting device, 10 socket, 11 mounting portion, 20 light emitting module, 21 board, 20a to 20f light emitting circuit, 22 light emitting element, 25 circuit element, 25a resistor, 25b protection element, 25c control element, 25c1 current driver, 25c2 current setting circuit, 25c3 constant current section, 25d negative characteristic thermistor, 25e resistor, 25f positive characteristic thermistor, 25g negative characteristic thermistor, 25h positive characteristic thermistor, 100 vehicle lighting fixture, 101 housing, Ia output current

Claims

1. A socket; A substrate provided on one end side of the socket; A light emitting element provided on the substrate; a control element provided on the substrate, the control element having a current driver having an output side electrically connected to the light emitting element, and a current setting circuit having an output side electrically connected to the current driver; a first circuit provided on the substrate, electrically connected to a first input side of the current setting circuit, and having a resistance value that changes depending on the ambient temperature of the light emitting element; a second circuit provided on the substrate, electrically connected to a second input side of the current setting circuit, and having a resistance value that changes depending on the ambient temperature of the light emitting element; Equipped with The current setting circuit includes: In a temperature region where the ambient temperature of the light-emitting element exceeds a first temperature and is equal to or lower than a second temperature higher than the first temperature, an output current flowing through the light-emitting element is reduced in accordance with an increase in the ambient temperature of the light-emitting element based on a change in the resistance value of the first circuit; A vehicle lighting device that, in a temperature region where the ambient temperature of the light-emitting element exceeds the second temperature, increases the rate at which the output current flowing to the light-emitting element is reduced as the ambient temperature of the light-emitting element rises, based on a change in the resistance value of the second circuit.

2. 2. The vehicle lighting device according to claim 1, wherein, in a temperature region where the ambient temperature of the light-emitting element is lower than the first temperature, the current setting circuit increases the output current flowing to the light-emitting element as the ambient temperature of the light-emitting element increases based on a change in the resistance value of the second circuit.

3. 2. The vehicle lighting device according to claim 1, wherein, in a temperature region where the ambient temperature of the light-emitting element is lower than the first temperature, the current setting circuit increases the output current flowing to the light-emitting element as the ambient temperature of the light-emitting element increases based on a change in the resistance value of the first circuit.

4. the first circuit has a first NTC thermistor or a first PTC thermistor, or the first NTC thermistor and the first PTC thermistor connected in series, 2. The vehicle lighting device according to claim 1, wherein the second circuit has a second negative characteristic thermistor, or a second positive characteristic thermistor, or the second negative characteristic thermistor and the second positive characteristic thermistor connected in series.

5. 5. The vehicle lighting device according to claim 4, wherein the current setting circuit generates a set current for setting the output current to be passed by the current driver to the light-emitting element based on a resistance value of the first negative characteristic thermistor, and adjusts the set current based on a resistance value of the second positive characteristic thermistor.

6. 6. The vehicle lighting device according to claim 5, wherein the current setting circuit generates the set current such that the output current decreases when the resistance value of the first negative characteristic thermistor decreases, and adjusts the set current to increase the rate at which the output current decreases when the resistance value of the second positive characteristic thermistor increases.

7. In a temperature region equal to or lower than the Curie temperature of the second positive temperature coefficient thermistor, 7. The vehicle lighting device according to claim 4, wherein the current setting circuit generates the set current that increases the output current based on a decrease in the resistance value of the second negative characteristic thermistor.

8. The vehicle lighting device according to claim 1; A housing in which the vehicle lighting device is mounted; A vehicle lamp equipped with:

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