Lighting circuit

Abstract

To improve visibility of an illumination portion to be illuminated in the daytime and at night.SOLUTION: A lighting circuit includes a first light source 21 and a second light source 22 that are turned on to illuminate the same illumination portion, and being configured to turn on both first light source 21 and second light source 22 in a preset first lighting state, and turn on the first light source 21 and turn off the second light source 22 in a preset second lighting state.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a lighting circuit. [Background technology]

[0002] Vehicles are equipped with various indicator lights that indicate the vehicle status and the usage status of devices. In this case, the display state of the indicator lights, particularly the luminance (brightness), is controlled to change between daytime and nighttime. For example, during the daytime when the surroundings are bright, the indicator lights are controlled to be lit at a higher luminance than at nighttime so that their illumination can be easily recognized. For example, Patent Document 1 describes a method of providing a dimming circuit for a single light source such as an LED (light-emitting diode) to control the current flowing therethrough during the daytime and at night, thereby controlling the luminance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 2807847 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the technology described in the above-mentioned Patent Document 1, the brightness is controlled by the amount of current flowing through one light source, and since there is a limit to the controllable range, it is difficult to produce an extreme difference in brightness between daytime and nighttime. Therefore, it is not possible to improve the visibility of the illuminated area that is illuminated both in daytime and nighttime.

[0005] An object of the present disclosure is to solve the problem that it is not possible to improve the visibility of an illuminated portion that is illuminated during the day and at night. [Means for solving the problem]

[0006] A lighting circuit according to an embodiment of the present disclosure includes: A first light source and a second light source are provided which are turned on to illuminate the same illumination portion, The lamp is configured so that, in a first lighting state that is preset, both the first light source and the second light source are turned on, and, in a second lighting state that is preset, the first light source is turned on and the second light source is turned off.

[0007] Moreover, a lighting device according to an embodiment of the present disclosure includes: A lighting circuit including a first light source and a second light source that are turned on to illuminate the same illumination portion; The illumination portion; Equipped with The lighting circuit is configured to turn on both the first light source and the second light source in a preset first lighting condition, and to turn on the first light source and turn off the second light source in a preset second lighting condition.

[0008] Further, a lighting method according to an embodiment of the present disclosure includes: A lighting method using a lighting circuit including a first light source and a second light source that are turned on to illuminate a same illumination portion, In a first lighting state that is preset, both the first light source and the second light source are turned on, and in a second lighting state that is preset, the first light source is turned on and the second light source is turned off. The structure is as follows. Effect of the Invention

[0009] By being configured as described above, the present disclosure can improve the visibility of the illuminated portion that is illuminated during the day and at night. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing an outline of the configuration of an illumination device according to the present disclosure; [Diagram 2] FIG. 2 is a diagram showing a configuration of an illumination circuit according to the present disclosure. [Diagram 3] FIG. 2 is a diagram illustrating the operation of a lighting circuit according to the present disclosure. [Figure 4]FIG. 2 is a diagram illustrating the operation of a lighting circuit according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] <Embodiment 1> The present disclosure will be described with reference to the drawings.

[0012] The illumination device in this embodiment illuminates an indicator light T (illumination portion) mounted in a vehicle. The indicator light T indicates, for example, the state of the vehicle or the state of use of the device, and is provided in equipment in the vehicle, such as an instrument panel. The illumination device is configured so that the luminance (brightness) of the indicator light T changes between daytime and nighttime. Note that daytime (first lighting condition) refers to a condition in which the brightness inside the vehicle is determined to be bright based on a preset criterion, as described below, and nighttime (second lighting condition) refers to a condition in which the brightness inside the vehicle is determined to be dark based on a preset criterion.

[0013] Specifically, as shown in Fig. 1, the lighting device includes an indicator light T, a lighting circuit 1 that illuminates the indicator light, and a control device 3 that controls the illumination state by the lighting circuit 1. The lighting circuit 1 is provided with an LED chip 2 that is a light source that is turned on to illuminate the indicator light T.

[0014] FIG. 2 shows an example of a specific circuit configuration of the lighting circuit 1. The LED chip 2 provided in the lighting circuit 1 includes two LEDs 21 and 22, both of which are light-emitting diodes that emit light when a current flows through them. That is, the two LEDs 21 and 22 are integrated in one LED chip 2 and arranged close to each other. Since one LED chip 2 is provided corresponding to one indicator light T, the two LEDs 21 and 22 are configured to illuminate the same indicator light T. In this case, when two LEDs are used to illuminate one indicator light, the illumination range may shift by the distance between the two LEDs, causing uneven brightness, and the device itself may become larger due to the distance between the two LEDs. However, by integrating the two LEDs 21 and 22 into one LED chip 2 as in this embodiment, the above-mentioned problems can be solved. That is, in this embodiment, the distance between the two LEDs is reduced, suppressing uneven brightness and making the device itself smaller. However, the two LEDs 21 and 22 are not necessarily limited to being integrated in one LED chip 2, and each LED may be provided in the lighting circuit 1. Also, each of the LEDs 21 and 22 is not limited to being composed of one LED, and each may be composed of an LED group consisting of a plurality of LEDs. For example, each of the LEDs 21 and 22 may be composed of an LED group consisting of a plurality of LEDs that are connected in series and light up simultaneously, and as an example, an LED group circuit that constitutes one LED 21 and an LED group circuit that constitutes the other LED 22 may be connected in parallel. Also, the two LEDs 21 and 22 are not limited to being composed of light-emitting diodes, and may be light sources that light up with any structure.

[0015] Here, one LED 21 is a day / night LED 21 (first light source) that is turned on both during the day and at night as described below, and the other LED 22 is a dimming LED 22 (second light source) that is turned on during the day and turned off at night. In other words, as described below, both the day / night LED 21 and the dimming LED 22 are turned on during the day, and only the day / night LED 21 is turned on at night.

[0016] The day / night LED 21 (one LED) and the dimming LED 22 (the other LED) are configured to have different luminances when turned on. In particular, the dimming LED 22 is configured to have a higher luminance when turned on than the day / night LED 21. As an example, the dimming LED 22 is configured to have a luminance that is about five times higher than the day / night LED 21. In this case, the ratio of luminance during daytime when both the day / night LED 21 and the dimming LED 22 are turned on and during nighttime when only the day / night LED 21 is turned on is approximately 6:1. However, the difference in luminance during lighting between the day / night LED 21 and the dimming LED 22 described above is an example, and any difference in luminance may be used. The day / night LED 21 and the dimming LED 22 may be configured to have the same luminance when turned on, or, conversely, the dimming LED 22 may be configured to have a lower luminance during lighting than the day / night LED 21. In this embodiment, the intensity of the light emitted by the LEDs 21 and 22 themselves is referred to as luminous intensity, and the brightness of the indicator lamp T illuminated by the LEDs 21 and 22 is referred to as luminance.

[0017] 2, the day / night LED 21 and the dimming LED 22 are connected to parallel circuits 11 and 12 that are branched and connected to the current source 10 in the lighting circuit. That is, of the parallel circuits 11 and 12 connected to the current source 10, the day / night LED 21 is connected to one circuit 11, and the dimming LED 22 is connected to the other circuit 12.

[0018] In addition, the dimming circuit 13 is connected to the other circuit 12, to which the dimming LED 22 is connected, downstream of the current source 10 from the dimming LED 22. Specifically, the other circuit 12 has electronic components connected downstream of the current source 10 in the order of the dimming LED 22, a diode, and a resistor, and the dimming circuit 13 is connected between the diode and the resistor. The dimming circuit 13 has a diode and a switch 14 connected upstream from the connection point with the other circuit 12, and is configured so that when the switch 14 is turned on, a current flows from the upstream side. Therefore, when the switch 14 is turned on and a current flows from the upstream side, the dimming circuit 13 passes through the connection point with the other circuit 12 and the resistor connected downstream of the other circuit 12. As a result, when a current flows through the dimming circuit 13, no current flows from the current source 10 to the dimming LED 22 of the other circuit 12.

[0019] The switch 14 of the dimming circuit 13 is controlled to be turned on / off by the control device 3. At this time, the control device 3 determines whether it is daytime or nighttime based on information that can be obtained by the vehicle, for example, and controls the switch 14 to be turned off when it is determined to be daytime, and to be turned on when it is determined to be nighttime. As an example, the control device 3 determines that it is daytime when the illuminance detected by an illuminance sensor mounted on the vehicle is equal to or greater than a preset reference value for determining that it is bright, and determines that it is nighttime when it is less than the reference value. As another example, the control device 3 may determine whether it is daytime or nighttime based on the lighting state of the headlights of the vehicle, and may determine that it is daytime when the headlights are off and that it is nighttime when the headlights are on. Furthermore, the control device 3 may determine whether it is daytime or nighttime based on the current time, for example, or may determine from any information.

[0020] Here, the operation of the lighting circuit will be described with reference to Fig. 3 and Fig. 4. Fig. 3 shows the state of the lighting circuit when the control device 3 determines that it is daytime. Since the switch 14 is turned off during the daytime, as shown by the arrows in Fig. 3, a current flows through each of the parallel circuits 11 and 12 connected to the current source 10 of the lighting circuit. In other words, during the daytime, a current flows through both the day / night LED 21 and the dimming LED 22, and they are turned on simultaneously. As a result, the indicator light T is illuminated by both the day / night LED 21 and the dimming LED 22, and therefore is turned on at a luminance higher than that during nighttime, which will be described later, so that the lighting of the indicator light T can be easily recognized even during the daytime when the surroundings are bright.

[0021] FIG. 4 shows the state of the lighting circuit when the control device 3 determines that it is nighttime. At night, the switch 14 is turned on, so that a current flows through the dimming circuit 13, as shown by the arrow in FIG. 4. That is, a current flows from the upstream of the dimming circuit 13 to the downstream side of the other circuit 12 of the parallel circuit 12. Then, of the parallel circuits 11 and 12 connected to the current source 10 of the lighting circuit, no current flows from the current source 10 to the other circuit 12 connected to the dimming circuit 13, and a current from the current source 10 flows only to one circuit 11. That is, at night, a current flows only to the day / night LED 21, so that the day / night LED 21 is turned on and the dimming LED 22 is turned off. As a result, the indicator lamp T is illuminated only by the day / night LED 21, so that it is turned on at a lower brightness than during the day.

[0022] As described above, in this embodiment, two LEDs 21 and 22 are provided to illuminate the same illumination portion such as the indicator light T, and the two LEDs 21 and 22 are turned on during the daytime, and only one LED 21 is turned on during the nighttime. This allows a difference in brightness of the indicator light T between daytime and nighttime, and improves the visibility of the indicator light T by the user both during daytime and nighttime. At this time, by configuring the luminance of the dimming LED 22, which is turned off at nighttime and turned on during the daytime, to be higher than the daytime and nighttime LED 21, a difference in brightness of the more illuminated indicator light T between daytime and nighttime can be achieved, and visibility can be further improved. Furthermore, as described above, the configuration can be achieved with a simple circuit such as the dimming circuit 13, and can be realized at low cost.

[0023] <Additional Notes> A part or all of the above-described embodiments can be described as follows: Below, an outline of the configurations of the lighting circuit, the lighting device, and the lighting method according to the present disclosure will be described. However, the present disclosure is not limited to the following configurations. (Appendix 1) A first light source and a second light source are provided which are turned on to illuminate the same illumination portion, The light source is configured to turn on both the first light source and the second light source in a preset first lighting state, and to turn on the first light source and turn off the second light source in a preset second lighting state. Lighting circuit. (Appendix 2) 2. The lighting circuit according to claim 1, The first light source and the second light source are integrated into one chip. Lighting circuit. (Appendix 3) 3. The lighting circuit according to claim 2, The first light source and the second light source are configured to have different luminous intensities when turned on. Lighting circuit. (Appendix 4) 4. The lighting circuit according to claim 3, The second light source is configured to have a higher luminous intensity when turned on than the first light source. Lighting circuit. (Appendix 5) 2. The lighting circuit according to claim 1, In the first lighting state, a current flows through the first light source and the second light source, In the second lighting state, a current flows through the first light source, and a current is caused to flow through a specific circuit connected to the second light source, so that no current flows through the second light source. Lighting circuit. (Appendix 6) 2. The lighting circuit according to claim 1, The first lighting situation is a situation determined to be a preset daytime time, and the second lighting situation is a situation determined to be a preset nighttime time. Lighting circuit. (Appendix 7) A lighting circuit including a first light source and a second light source that are turned on to illuminate the same illumination portion; The illumination portion; A lighting device comprising: The lighting circuit is configured to light both the first light source and the second light source in a preset first lighting state, and to light the first light source and turn off the second light source in a preset second lighting state. Lighting device. (Appendix 8) A lighting method using a lighting circuit including a first light source and a second light source that are turned on to illuminate a same illumination portion, In a first lighting state that is preset, both the first light source and the second light source are turned on, and in a second lighting state that is preset, the first light source is turned on and the second light source is turned off. How to light it. [Explanation of symbols]

[0024] 1 Lighting circuit 11,12 parallel circuit 13 Dimming circuit 14 Switch 2 LED chips 21 Day / night LED (one LED) 22 Dimming LED (other LED) 3. Control device

Claims

1. A first light source and a second light source are provided which are turned on to illuminate the same illumination portion, The light source is configured to turn on both the first light source and the second light source in a preset first lighting state, and to turn on the first light source and turn off the second light source in a preset second lighting state. Lighting circuit.

2. 2. The lighting circuit according to claim 1, The first light source and the second light source are integrated into one chip. Lighting circuit.

3. 3. The lighting circuit according to claim 2, The first light source and the second light source are configured to have different luminous intensities when turned on. Lighting circuit.

4. 4. The lighting circuit according to claim 3, The second light source is configured to have a higher luminous intensity when turned on than the first light source. Lighting circuit.

5. 2. The lighting circuit according to claim 1, In the first lighting state, a current flows through the first light source and the second light source, In the second lighting state, a current flows through the first light source, and a current does not flow through the second light source by causing a current to flow through a specific circuit connected to the second light source. Lighting circuit.

6. 2. The lighting circuit according to claim 1, The first lighting situation is a situation determined to be a preset daytime time, and the second lighting situation is a situation determined to be a preset nighttime time. Lighting circuit.

7. A lighting circuit including a first light source and a second light source that are turned on to illuminate the same illumination portion; The illumination portion; A lighting device comprising: The lighting circuit is configured to light both the first light source and the second light source in a preset first lighting state, and to light the first light source and turn off the second light source in a preset second lighting state. Lighting device.

8. A lighting method using a lighting circuit including a first light source and a second light source that are turned on to illuminate a same illumination portion, In a first lighting state that is preset, both the first light source and the second light source are turned on, and in a second lighting state that is preset, the first light source is turned on and the second light source is turned off. How to light it.

Images