Control apparatus of vehicular light unit and vehicular light unit

Abstract

To suppress a light reduction in a light source.SOLUTION: A control apparatus of a vehicular light unit comprises: a switch that is electrically connected in parallel to each of a plurality of light sources that are electrically serially connected; and a switch control part that switches ON and OFF of the switch so that a pulse current is supplied to each light source. The switch control part performs control for supplying the pulse current where a duty period varies for the plurality of light sources, and controls the switch so as to supply a compensation pulse current for compensating for a first pulse current in addition to the first pulse current to a first light source in the case where a specific control for supplying a second pulse current where the duty period is smaller than that of the first pulse current for a second light source that is different from the first light source within a period when the first pulse current is supplied to the first light source is performed.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a control device for vehicle lamps and a vehicle lamp.

Background Art

[0002] A configuration in which lighting and extinguishing of a plurality of light sources are controlled by a single drive circuit is known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the vehicle lamp described in Patent Document 1, a plurality of light sources are electrically connected in series, and switches are electrically connected in parallel for each light source, and the lighting and extinguishing of the light sources are switched by switching on and off the switches. However, when trying to light the second light source while one light source is lit and switching the switch, a period occurs during which no current flows through both light sources or the current value decreases from the time the switch is switched until the light source boosts to a predetermined voltage. During this period, both light sources will go out. For example, when performing pulse width modulation control, if the extinguishing period occurs in each cycle, the light source will be dimmed accordingly.

[0005] The present invention has been made in view of the above, and an object thereof is to provide a control device for vehicle lamps and a vehicle lamp capable of suppressing dimming of a light source.

Means for Solving the Problems

[0006] The control device for a vehicle lamp according to the present invention includes a switch electrically connected in parallel to each of a plurality of light sources electrically connected in series, and a switch control unit that switches on and off the switch so that a pulsed current is supplied to each of the light sources. The switch control unit performs control to supply pulsed currents with different duty periods to the plurality of light sources. When performing specific control to supply a second pulsed current having a duty period smaller than that of the first pulsed current to a second light source different from the first light source within a period of supplying the first pulsed current to the first light source, the switch is controlled to supply, in addition to the first pulsed current, a complementary pulsed current that complements the first pulsed current to the first light source.

[0007] The vehicle lamp according to the present invention includes a plurality of light sources and the above-described control device for a vehicle lamp that controls the plurality of light sources.

Advantages of the Invention

[0008] According to the present invention, it is possible to provide a control device for a vehicle lamp and a vehicle lamp that can suppress dimming in a light source.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of a control device for a vehicle lamp and a vehicle lamp according to the present invention will be described with reference to the drawings. Note that the present invention is not limited to this embodiment. In addition, the components in the following embodiments include those that can be replaced by those skilled in the art and are easy to replace, or those that are substantially the same.

[0011] FIG. 1 is a diagram schematically showing an example of a vehicle lamp 100 according to the present embodiment. As shown in FIG. 1, the vehicle lamp 100 according to the present embodiment includes a light source unit 10 and a control device (control device for vehicle lamp) 20.

[0012] The light source unit 10 has a plurality of light sources 11. In the present embodiment, for example, it has two light sources 11. As the plurality of light sources 11, for example, light emitting elements such as LEDs can be used. The plurality of light sources 11 are electrically connected in series. Hereinafter, when distinguishing the plurality of light sources 11, they are denoted as the first light source 11a and the second light source 11b. The plurality of light sources 11 are the light sources of the functional lamp constituting the vehicle lamp 100. In the present embodiment, the first light source 11a can be, for example, the light source of the turn lamp. In this case, the second light source 11b can be the light source of a functional lamp different from the turn lamp, such as a clearance lamp, a daytime running lamp, etc. Hereinafter, it is assumed that the second light source 11b is the light source of the clearance lamp.

[0013] The control device 20 controls a plurality of light sources 11 of the light source unit 10. The control device 20 is a single control circuit. The control device 20 includes a plurality of switches 21, a switch control unit 22, and a power control unit 23.

[0014] The switches 21 are electrically connected in parallel to each of the light sources 11. One switch 21 is provided for one light source 11. Hereinafter, when distinguishing the switches 21, they are denoted as the first switch 21a and the second switch 21b. In the present embodiment, the first switch 21a is electrically connected in parallel to the first light source 11a, and the second switch 21b is electrically connected in parallel to the second light source 11b.

[0015] The switch 21 is capable of switching between on and off. When the switch 21 is in the off state, no current flows through the switch 21, and current flows through the light source 11 connected in parallel to the switch 21. On the other hand, when the switch 21 is in the on state, since the light source 11 connected in parallel to the switch 21 is short-circuited, no current flows through the light source 11, and current flows through the switch 21. Therefore, by turning off the switch 21, the light source 11 connected in parallel to the switch 21 lights up. Also, by turning on the switch 21, the light source 11 connected in parallel to the switch 21 goes out.

[0016] The switch control unit 22 controls the switch 21 based on, for example, a control signal from a lighting instruction unit 30 provided on the vehicle side. The control signal is a control signal for lighting or extinguishing the light source 11. When a predetermined operation for lighting a function lamp is performed by the driver, the lighting instruction unit 30 generates and outputs a control signal so as to light the function lamp corresponding to the predetermined operation.

[0017] The switch control unit 22 switches the on and off of the switch 21 so that a pulse current is supplied to each light source 11. The switch control unit 22 performs pulse width modulation control to supply pulse currents with different duty periods to the plurality of light sources 11.

[0018] In this pulse width modulation control, the switch control unit 22 may perform control (specific control) to supply a second pulse current having a duty period smaller than that of the first pulse current to a second light source 11b different from the first light source 11a during a period in which the first pulse current is supplied to the first light source 11a, which is one of the plurality of light sources 11. When performing the specific control, the switch control unit 22 controls the first switch 21a to supply a complementary pulse current that complements the first pulse current to the first light source 11a in addition to the first pulse current.

[0019] The switch control unit 22 includes a storage unit 24 and a processing unit 25. The storage unit 24 stores programs and data related to the control of the switch control unit 22. For example, the storage unit 24 stores reference data and complementary data. The reference data includes first drive data D1 and second drive data D2. The first drive data D1 is data for driving the first switch 21a to supply the first pulse current to the first light source 11a. The second drive data D2 is drive data for driving the second switch 21b to supply the second pulse current to the second light source 11b. The complementary data DS is drive data for driving the first switch 21a to supply the complementary pulse current to the first light source 11a. The processing unit 25 outputs a control signal regarding the switching of the switch 21 based on the data stored in the storage unit 24.

[0020] The power control unit 23 controls the power supplied to the light source unit 10, that is, the plurality of light sources 11. The power control unit 23, for example, converts the voltage of the vehicle-side power source unit 40 to a predetermined voltage corresponding to the light source unit 10 and applies it to the light source unit 10. As the power control unit 23, for example, a DC-DC converter or the like is used.

[0021] Next, the operation of the vehicle lamp 100 configured as described above will be explained. FIGS. 2 and 3 are timing charts showing an example of the control of the switch 21 and the lighting and extinguishing timings of the light source 11. In FIGS. 2 and 3, the vertical axis represents the magnitude of the current, and the horizontal axis represents time. When a predetermined operation for lighting the function lamp is performed by the driver in the vehicle, the lighting instruction unit 30 generates and outputs a control signal so as to light the function lamp corresponding to the driver's operation.

[0022] For example, when a predetermined operation for lighting the turn lamp is performed by the driver, the lighting instruction unit 30 generates and outputs a command signal for instructing to light the first light source 11a which is the light source of the turn lamp. When the switch control unit 22 receives the command signal from the lighting instruction unit 30, it performs control to light the first light source 11a according to the command signal.

[0023] In this case, in the switch control unit 22, the processing unit 25 extracts the first drive data D1 stored in the storage unit 24, generates a first control signal S1 for controlling the first switch 21a based on the first drive data D1, and outputs the generated first control signal S1. FIG. 2 is a timing chart showing the on and off timings of the first switch 21a and the current supplied to the first light source 11a in correspondence. As shown in FIG. 2, the first control signal S1 is a pulse signal in which a period for turning off the first switch 21a and a period for turning on the first switch 21a are alternately repeated. The first light source 11a lights during the period when the first switch 21a is off. The first light source 11a goes out during the period when the first switch 21a is on. Therefore, a first pulse current C1 based on the first control signal S1 flows through the first light source 11a. As shown in FIG. 2, when the first light source 11a is lit from the extinguished state, after the first switch 21a is switched from the on state to the off state, the current value flowing through the first light source 11a gradually increases until the first light source 11a is boosted to a predetermined voltage.

[0024] Further, for example, when a predetermined operation is performed by the driver to turn on the clearance lamp, the lighting instruction unit 30 generates and outputs a command signal for instructing to turn on the second light source 11b, which is the light source of the clearance lamp. When the switch control unit 22 receives the command signal from the lighting instruction unit 30, it performs control to turn on the second light source 11b according to the command signal.

[0025] In this case, in the switch control unit 22, the processing unit 25 extracts the second drive data D2 stored in the storage unit 24, generates a second control signal S2 for controlling the second switch 21b based on the second drive data D2, and outputs the generated second control signal S2. FIG. 3 is a timing chart showing the on and off timings of the second switch 21b and the current supplied to the second light source 11b in correspondence. As shown in FIG. 3, the second control signal S2 is a pulse signal in which the period for turning off the second switch 21b and the period for turning on the second switch 21b are alternately repeated. The second light source 11b lights up during the period when the second switch 21b is off. The second light source 11b goes out during the period when the second switch 21b is on. Note that the lighting period of the second light source 11b is shorter than that of the first light source 11a. That is, a pulse current with a smaller duty period of the lighting period is supplied to the second light source 11b than to the first light source 11a. Therefore, a second pulse current C2 based on the second control signal S2 flows through the second light source 11b. As shown in FIG. 3, when the second light source 11b is turned on from the off state, after the second switch 21b is switched from the on state to the off state, the current value flowing through the second light source 11b gradually increases until the second light source 11b is boosted to a predetermined voltage.

[0026] Further, for example, when a predetermined operation is performed by the driver to turn on the turn lamp and the clearance lamp simultaneously, the lighting instruction unit 30 generates and outputs command signals for turning on the first light source 11a and the second light source 11b respectively. When the switch control unit 22 receives the command signal from the lighting instruction unit 30, it performs control to turn on the first light source 11a and the second light source 11b according to the command signal.

[0027] In this case, in the switch control unit 22, the processing unit 25 extracts the first drive data D1 and the second drive data D2 stored in the storage unit 24. The processing unit 25 generates a first control signal S1 for controlling the first switch 21a based on the first drive data D1, and generates a second control signal S2 for controlling the second switch 21b based on the second drive data D2.

[0028] When controlling the first switch 21a and the second switch 21b in parallel, the processing unit 25 determines whether or not the control corresponds to specific control. That is, the processing unit 25 determines whether or not there is a timing at which the second pulse current C2 is supplied to the second light source 11b during the period in which the first pulse current C1 is supplied to the first light source 11a. When the processing unit 25 determines that it does not correspond to specific control, the processing unit 25 outputs the first control signal S1 to the first switch 21a and outputs the second control signal S2 to the second switch 21b.

[0029] When the processing unit 25 determines that it corresponds to specific control, for the first control signal S1, the processing unit 25 controls the first switch 21a so as to supply a complementary pulse current CS that complements the first pulse current C1 in addition to the first pulse current C1 to the first light source 11a. FIGS. 4 and 5 are timing charts showing the on and off timings of the first switch 21a and the second switch 21b in correspondence with the currents supplied to the first light source 11a and the second light source 11b. Note that FIG. 4 shows the state before complementation by the complementary pulse current. In FIGS. 4 and 5, the vertical axis represents the magnitude of the current, and the horizontal axis represents time.

[0030] When supplying two or more types of pulsed currents with different duty cycles to a plurality of light sources 11 electrically connected in series as in this embodiment, for example, within the period of supplying the first pulsed current C1 with a large duty cycle to the first light source 11a, when starting to supply the second pulsed current C2 with a small duty cycle to the second light source 11b, as shown in FIG. 4, from the start of supplying the second pulsed current C2 until a predetermined voltage is reached, during the boosting period, the current values flowing through the first light source 11a and the second light source 11b decrease, and the first light source 11a and the second light source 11b are in a state of being turned off or dimmed. When such a dimming period occurs, the brightness of the first light source 11a and the second light source 11b when lit decreases with respect to the expected brightness.

[0031] Therefore, as shown in FIG. 5, the switch control unit 22 generates the first control signal S1 so as to supply the complementary pulsed current CS for complementing the first pulsed current C1 to the first light source 11a. The processing unit 25 generates the first control signal S1 based on the complementary data DS stored in the storage unit 24. The complementary data DS is data for driving the first switch 21a so as to supply a pulsed current having the same current value as the first pulsed current C1 to the complementary pulsed current CS only for the period corresponding to the boosting period of the second light source 11b. The complementary data DS is preset based on the boosting period of the second light source 11b and the current value of the first pulsed current C1. In the example shown in FIG. 5, the switch control unit 22 controls so that the complementary pulsed current CS is supplied continuously at the timing of starting the supply of the first pulsed current C1. That is, the switch control unit 22 controls so that the complementary pulsed current CS is supplied immediately before the first pulsed current C1 is supplied.

[0032] Here, for a plurality of light sources 11 electrically connected in series as in the present embodiment, for example, when a first pulse current C1 is supplied to the first light source 11a and a second pulse current C2 is supplied to the second light source 11b, and only the supply of the second pulse current C2 is terminated, at the time when the supply of the second pulse current C2 ends, an excessive current flows through the first light source 11a, causing damage to the first light source 11a. Therefore, the switch control unit 22 generates the first control signal S1 and the second control signal S2 so as not to terminate the supply of the second pulse current C2 to the second light source 11b within the period during which the first pulse current C1 is supplied to the first light source 11a. In this case, as shown in FIG. 5, the switch control unit 22 generates the first control signal S1 and the second control signal S2 so that the timings at which the supply of the first pulse current C1 and the second pulse current C2 end are the same. When the timings at which the supply of the first pulse current C1 and the second pulse current C2 end are the same, the switch control unit 22 can generate the first control signal S1 so as to supply a complementary pulse current CS continuously following the timing at which the supply of the first pulse current C1 starts when performing the specific control. That is, the switch control unit 22 generates the first control signal S1 so that the complementary pulse current CS is supplied immediately before the supply of the first pulse current C1 starts.

[0033] As described above, the control device 20 according to the present embodiment includes switches 21 electrically connected in parallel to each of a plurality of light sources 11 electrically connected in series, and a switch control unit 22 that switches the on and off of the switches 21 so that a pulse current is supplied to each light source 11. The switch control unit 22 performs control to supply pulse currents having different duty periods to the plurality of light sources 11. When performing specific control to supply a second pulse current C2 having a duty period smaller than that of the first pulse current C1 to a second light source 11b different from the first light source 11a within the period during which the first pulse current C1 is supplied to the first light source 11a, the switch control unit 22 controls the switch 21 so as to supply a complementary pulse current CS that complements the first pulse current C1 in addition to the first pulse current C1 to the first light source 11a.

[0034] According to this configuration, when the supply of the second pulse current C2 to the second light source 11b is started during the period in which the first pulse current C1 is supplied to the first light source 11a, the extinguishing period of the first light source 11a until the second light source 11b boosts the voltage can be complemented by lighting the first light source 11a with the complementary pulse current CS. Thereby, a decrease in the brightness of the first light source 11a in pulse width modulation control can be suppressed.

[0035] In the control device 20 according to the present embodiment, the switch control unit 22 controls the switch 21 so as not to end the supply of the second pulse current C2 to the second light source 11b during the period in which the first pulse current C1 is supplied to the first light source 11a.

[0036] According to this configuration, since it is possible to avoid an excessive current from flowing through the first light source 11a at the time of the end of the supply of the second pulse current C2, it is possible to prevent damage to the first light source 11a.

[0037] In the control device 20 according to the present embodiment, the switch control unit 22 controls the switch 21 so that the timings of the end of the supply of the first pulse current C1 and the second pulse current C2 are the same.

[0038] According to this configuration, by making the timings of the end of the supply of the first pulse current C1 and the second pulse current C2 the same, it is possible to easily set the timing of the supply of the complementary pulse current CS.

[0039] In the control device 20 according to the present embodiment, when performing specific control, the switch control unit 22 controls so as to supply the complementary pulse current CS continuously following the timing of the start of the supply of the first pulse current C1.

[0040] According to this configuration, by controlling so as to supply the complementary pulse current CS continuously following the timing of the start of the supply of the first pulse current C1, it is possible to appropriately set the timing of the supply of the complementary pulse current CS while preventing damage to the first light source 11a.

[0041] In the control device 20 according to this embodiment, the complementary pulse current CS has the same current value as the first pulse current C1, and is a pulse current during a period corresponding to the boosting period from when a voltage is applied to the second light source 11b until current flows.

[0042] According to this configuration, by lighting the first light source 11a with the complementary pulse current CS, the extinguishing period of the first light source 11a can be appropriately complemented.

[0043] In the control device 20 according to this embodiment, the first light source 11a is a light source of a turn lamp and is connected to the position where the highest voltage is applied to the power supply unit 40 among the plurality of light sources 11.

[0044] According to this configuration, as long as the terminal on the high-potential side of the first light source 11a among the plurality of light sources 11 is not grounded, the lighting of the first light source 11a can be maintained. Thereby, the loss of function of the turn lamp can be suppressed.

[0045] The vehicle lamp 100 according to this embodiment includes a plurality of light sources 11 and the above-described control device 20 that controls the plurality of light sources 11.

[0046] According to this configuration, since the control device 20 capable of suppressing a decrease in the brightness of the first light source 11a among the plurality of light sources 11 is provided, the vehicle lamp 100 that can be lit with sufficient brightness can be provided.

[0047] FIG. 6 is a diagram schematically showing another example of a control device for a vehicle lamp. As shown in FIG. 6, the vehicle lamp 200 includes a light source unit 110 and a control device (control device for a vehicle lamp) 120.

[0048] In the example shown in FIG. 6, the light source unit 110 has three light sources 11 as a plurality of light sources. The configuration of each light source 11 is the same as that in the above embodiment. When distinguishing the plurality of light sources 11, they are denoted as the first light source 11a, the second light source 11b, and the third light source 11c. The first light source 11a can be, for example, a light source of a turn lamp. In this case, the second light source 11b and the third light source 11c can be light sources of functional lamps different from the turn lamp, such as a clearance lamp. Hereinafter, it is assumed that the second light source 11b is a light source of the first clearance lamp. Also, it is assumed that the third light source 11c is a light source of the second clearance lamp. The first clearance lamp and the second clearance lamp are different clearance lamps mounted on one vehicle lamp 100. Also, it is assumed that the turn lamp, the first clearance lamp, and the second clearance lamp are arranged so that they can be lit simultaneously.

[0049] The control device 120 controls the plurality of light sources 11 of the light source unit 110. The control device 120 is one control circuit. The control device 120 includes a plurality of switches 21, a switch control unit 22, and a power control unit 23.

[0050] The switches 21 are electrically connected in parallel to each of the light sources 11. When distinguishing the switches 21, they are denoted as the first switch 21a, the second switch 21b, and the third switch 21c. In the present embodiment, the first switch 21a is electrically connected in parallel to the first light source 11a, the second switch 21b is electrically connected in parallel to the second light source 11b, and the third switch 21c is electrically connected in parallel to the third light source 11c.

[0051] Next, the operation of the vehicle lamp 200 configured as described above will be described. For example, when a predetermined operation is performed by the driver to simultaneously turn on the turn lamp, the first clearance lamp, and the second clearance lamp, the lighting instruction unit 30 generates and outputs command signals for turning on the first light source 11a, the second light source 11b, and the third light source 11c, respectively. When the switch control unit 22 receives the command signal from the lighting instruction unit 30, it performs control to turn on the first light source 11a, the second light source 11b, and the third light source 11c according to the command signal.

[0052] In the switch control unit 22, the processing unit 25 extracts the first drive data D1, the second drive data D2, and the third drive data D3 stored in the storage unit 24. The processing unit 25 generates a first control signal S1 for controlling the first switch 21a based on the first drive data D1, generates a second control signal S2 for controlling the second switch 21b based on the second drive data D2, and generates a third control signal S3 for controlling the third switch 21c based on the third drive data D3.

[0053] When controlling the first switch 21a, the second switch 21b, and the third switch 21c in parallel, the processing unit 25 determines whether the control corresponds to specific control. That is, the processing unit 25 determines that it corresponds to the first specific control when there is a timing for supplying the second pulse current C2 to the second light source 11b or a timing for supplying the third pulse current C3 to the third light source 11c during the period of supplying the first pulse current C1 to the first light source 11a. Further, the processing unit 25 determines that it corresponds to the second specific control when there is a timing for supplying the third pulse current C3 to the third light source 11c during the period of supplying the second pulse current C2 to the second light source 11b.

[0054] When the processing unit 25 determines that it does not correspond to specific control, it outputs the first control signal S1 to the first switch 21a, outputs the second control signal S2 to the second switch 21b, and outputs the third control signal S3 to the third switch 21c.

[0055] When the processing unit 25 determines that it corresponds to the first specific control, for the first control signal S1, the first switch 21a is controlled to supply a complementary pulse current CS that complements the first pulse current C1 in addition to the first pulse current C1 to the first light source 11a. Further, when the processing unit 25 determines that it corresponds to the second specific control, for the second control signal S2, the second switch 21b is controlled to supply a complementary pulse current CS that complements the second pulse current C2 in addition to the second pulse current C2 to the second light source 11b.

[0056] Hereinafter, the case where it corresponds to the first specific control and the second specific control will be described. FIGS. 7 and 8 are timing charts showing the on and off timings of the first switch 21a, the second switch 21b, and the third switch 21c in correspondence with the currents supplied to the first light source 11a, the second light source 11b, and the third light source 11c. Note that FIG. 7 shows the state before complementation by the complementary pulse current. In FIGS. 7 and 8, the vertical axis represents the magnitude of the current, and the horizontal axis represents time.

[0057] As shown in FIG. 7, during the boosting period from the start of supply of the second pulse current C2 until a predetermined voltage is reached, the current values flowing through the first light source 11a and the second light source 11b decrease, and the first light source 11a and the second light source 11b are in a state of being turned off or dimmed. Note that during this boosting period, since no current is flowing through the third light source 11c, there is no influence on the third light source 11c. Also, during the boosting period from the start of supply of the third pulse current C3 until a predetermined voltage is reached, the current values flowing through the first light source 11a, the second light source 11b, and the third light source 11c decrease, and the first light source 11a and the second light source 11b are in a state of being turned off or dimmed. Note that the lighting period of the second light source 11b is shorter than that of the first light source 11a. That is, a pulse current with a smaller duty period of the lighting period is supplied to the second light source 11b than to the first light source 11a. Note that the lighting period of the third light source 11c is shorter than that of the second light source 11b. That is, a pulse current with a smaller duty period of the lighting period is supplied to the third light source 11c than to the first light source 11a and the second light source 11b.

[0058] Therefore, as shown in FIG. 8, the switch control unit 22 generates a first control signal S1 to supply a complementary pulse current CS1 for complementing the first pulse current C1 to the first light source 11a. By this process, the first switch 21a is controlled so that a pulse current having the same current value as the first pulse current C1 is supplied as the complementary pulse current CS1 only for a period corresponding to the boosting period of the second light source 11b.

[0059] Also, the switch control unit 22 generates a second control signal S2 to supply a complementary pulse current CS2 for complementing the second pulse current C2 to the second light source 11b. By this process, the second switch 21b is controlled so that a pulse current having the same current value as the second pulse current C2 is supplied as the complementary pulse current CS2 only for a period corresponding to the boosting period of the third light source 11c.

[0060] As shown in FIG. 8, within the supply period of the first pulse current C1, the extinguishing periods due to the start of lighting of the second light source 11b and the third light source 11c occur twice. Also, within the supply period of the second pulse current C2, the extinguishing period due to the start of lighting of the third light source 11c occurs once.

[0061] Thus, within the supply period of a pulse current having a relatively long duty period, the more the supply frequency of a pulse current having a relatively short duty period, the more current loss occurs and the extinguishing period becomes longer. Therefore, the switch control unit 22 can control so that the supply period of the complementary pulse current becomes longer as the supply frequency of the pulse current having a relatively short duty period increases within the supply period of the pulse current having a relatively long duty period. Thereby, the complementary pulse current can be appropriately supplied according to the current loss period of the pulse current having a relatively long duty period.

Explanation of Reference Numerals

[0062] 10,110… Light source unit, 11… Light source, 11a… First light source, 11b… Second light source, 11c… Third light source, 20,120… Control device, 21… Switch, 21a… First switch, 21b… Second switch, 21c… Third switch, 22… Switch control unit, 23… Power control unit, 24… Memory unit, 25… Processing unit, 30… Lighting instruction unit, 40… Power supply unit, 100,200… Vehicle lamp

Claims

1. A switch electrically connected in parallel to each of a plurality of light sources electrically connected in series, and a switch control unit that switches on and off the switch so that a pulsed current is supplied to each of the light sources comprising: The switch control unit performs control to supply pulsed currents having different duty periods to the plurality of light sources, and when performing specific control to supply a second pulsed current having a duty period smaller than that of the first pulsed current to a second light source different from the first light source during a period in which the first pulsed current is supplied to the first light source, the switch is controlled to supply, in addition to the first pulsed current, a complementary pulsed current that complements the first pulsed current to the first light source A control device for a vehicle lamp.

2. The switch control unit controls the switch so as not to end the supply of the second pulsed current to the second light source during a period in which the first pulsed current is supplied to the first light source The control device for a vehicle lamp according to claim 1.

3. The switch control unit controls the switch so that the timings at which the supply of the first pulsed current and the second pulsed current end are the same The control device for a vehicle lamp according to claim 2.

4. When performing the specific control, the switch control unit controls to supply the complementary pulsed current continuously following the timing at which the supply of the first pulsed current starts The control device for a vehicle lamp according to claim 1.

5. The complementary pulsed current has the same current value as the first pulsed current, and is a pulsed current for a period corresponding to a voltage boost period from when a voltage is applied to the second light source until current flows The control device for a vehicle lamp according to claim 1.

6. The switch control unit controls the switch so that the supply period of the complementary pulsed current becomes longer as the number of times the second pulsed current is supplied during the supply period of the first pulsed current increases for each first pulsed current The control device for a vehicle lamp according to claim 1.

7. The first light source is a light source of a turn lamp and is connected to a position having the highest voltage with respect to a power supply unit among the plurality of light sources The control device for a vehicle lamp according to claim 1.

8. A plurality of light sources, and a control device for a vehicle lamp according to any one of claims 1 to 7, which controls the plurality of light sources A vehicle lamp comprising:

Images