JP4222192B2 - Lighting device - Google Patents

Description

  The present invention relates to a lighting device for a vehicle interior. Specifically, the present invention relates to a lighting device installed on a roof portion in a vehicle compartment.

An illuminating device (room lamp) for illuminating the interior of the vehicle is installed on the roof of the interior of the vehicle for the purpose of improving safety when getting on or off at night. In such an illumination device, a bulb is generally used as a light source. In recent years, lighting devices using light emitting diodes (hereinafter referred to as LEDs) as light sources have started to be used from the viewpoints of long life and power saving (for example, see Patent Document 1).
5-1598

In a conventional illumination device using an LED as a light source, an LED that emits white light is used so that it can be used for illumination. White light obtained by mixing LEDs of the three primary colors of red, blue, and green has high color reproducibility and fine color adjustment is possible, but it requires an advanced control device to control the color balance and is mounted. To be very expensive.
In addition, the LED that emits white light by mixing the emitted light of the blue LED and the yellow phosphor excited by the emitted light is likely to vary in color, and the color reproducibility of the red object is poor. there were.
Further, conventionally, a lighting device is generally used that switches between a state in which an LED is lit (illumination state) and a state in which the LED is unlit (non-illumination state) in conjunction with opening or closing of a switch or a door. Was monotonous.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicular illumination device capable of configuring a desired illumination color at a low cost.

The present invention has the following configuration in order to solve the above object.
A plurality of two types of white LEDs having different emission colors are provided, and illumination by the emitted light of each of the two types of white LEDs and illumination by a color obtained by mixing the emitted light of each of the two types of white LEDs are performed. It is an illuminating device installed in a roof part.

According to such a configuration, since the two types of white LED light sources that satisfy the illumination application alone are provided, two types of illumination colors can be obtained by lighting each white LED alone and using it. Of course, it is possible to obtain illumination with an intermediate color between the two light sources by mixing the two light sources. Therefore, it is possible to freely adjust the illumination color with a color between two types of illumination colors.
In addition, by adopting an LED light source with a small calorific value, continuous lighting for a long time is possible, and the range of usage is expanded.
Furthermore, since the illumination color can be easily adjusted simply by controlling the illuminance balance of each LED light source, the control device becomes a simple and low-cost illumination device.

  In said structure, since several LED light sources combine the LED light source from which a lighting aspect differs, the illuminating device with which the variation of an illumination aspect is abundant can be comprised. Then, an appropriate illumination mode can be selected according to the situation, and various illumination effects can be obtained. Further, in addition to the original purpose of improving the visibility of the light irradiation area, it can also be used for the purpose of improving the decoration of the vehicle interior.

  For example, a plurality of LED light sources that emit light emission illuminance of two types of LEDs at a predetermined ratio in the first illumination state, and a light emission illuminance of the two types of LEDs in the second illumination state are predetermined. A plurality of LED light sources can be configured by combining a plurality of LED light sources that emit light at a ratio. If comprised in this way, the illuminating device which can select three aspects, for example, an ON state (1st lighting state), an OFF state, or the ON state (2nd lighting state) interlock | cooperated with opening / closing of a door is comprised. . In this case, a plurality of LEDs that are turned on in the first illumination state and a plurality of LEDs that are turned on in the second illumination state can be used in combination. In addition to the first illumination state and the second illumination state, the color mixing ratio of the two types of LEDs can be changed as appropriate, so that the illumination can be adapted to the user's preference.

Note that the present invention is not limited to the above two types of LEDs, and three or more LED light sources having different light emission modes may be combined to form a plurality of LED light sources of the present invention.
A light transmissive lens can be provided on the light emission side of the LED light source. In this case, the light emitted from the LED light source is irradiated into the vehicle interior via the lens. This lens can be subjected to a desired cutting process to change the appearance of light emitted from the outside. Such a process can be performed on a partial region of the lens, and such a change can be applied only to the light emitted through the region. In addition, it is possible to perform a cutting process in a different mode for each region so that light emitted from each region has a unique light emission mode.
A diffusion film is provided between the lens and the light source, and the light from the LED light source is diffused by the diffusion film to reach the lens in a state where the light emission colors of the two types of LEDs are almost mixed and irradiate the vehicle interior. Will be.

In the present invention, an LED light source is used as the light source. The LED light source is a light source suitable for continuous lighting for a long time since it has low power consumption and heat generation and has a long life. Moreover, since it is small, the whole lighting device can be reduced in size and thickness. Therefore, the installation space can be reduced, and the passenger compartment space is not occupied. In addition, the small size increases the degree of freedom of the mounting position, and the interior is excellent.
The type of LED used for the LED light source is not particularly limited, and various types such as a shell type and a chip type can be adopted.

  The plurality of two types of LED light sources are arranged so that the LED light sources are arranged in a matrix when viewed from the design surface side, for example. By arranging in a matrix shape, the emission colors of the two types of LEDs are likely to be mixed, as well as point light, line light, surface light, light of a specific shape (for example, T-shape), etc. Various modes of light can be emitted externally. Therefore, it is possible to select an appropriate light emission mode as required, for example, lighting of only the passenger seat, simultaneous lighting of the passenger seat and the rear seat, lighting of only the console box, or lighting of the central passage in a wagon car, etc. For example, the illumination device can perform illumination on a desired irradiation area.

  The light emission color of the LED light source is preferably a single color that can be used, and white to amber LEDs are used. The selection of the two types of LED light sources is preferably a combination with different color temperatures as much as possible in order to give a wide range of color changes. For example, it is preferable to combine blue white and amber LEDs.

  The lighting device of the present invention is used by being installed on a roof portion in a vehicle compartment. For example, it can be used by being installed in a roof portion between the driver seat and the passenger seat, a roof portion that is substantially equidistant from the driver seat, the passenger seat, and the rear seat.

Hereinafter, a specific configuration of the present invention will be described with reference to the drawings.
FIG. 1 is a side view of a vehicle interior lighting device 10 (hereinafter referred to as “lighting device 10”) according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG. It is a thing. FIG. 3 shows a front view. FIG. 4 shows an example of lighting control of two types of LEDs.

The illuminating device 10 has a substantially rectangular parallelepiped shape, and includes a case 11 having a rectangular opening for light emission on one side, a lens 12, a diffusion film 13, a reflecting surface 14, a plurality of daylight color LEDs 20, a plurality of light bulb color LEDs 21, and a substrate 22. Is provided. The daylight color LED 20 is a surface mount type (SMD type) LED, and the color temperature of the emitted light is 6000K, and the light looks visually white. On the other hand, the light bulb color LED 21 is also a surface mount type (SMD type) LED, but the color temperature of the emitted light is 2800K, and it is a light that looks like a yellowish white like a light bulb visually. Therefore, the daylight color LED 20 has a higher color temperature than the light bulb color LED 21.
The daylight color LED 20 and the light bulb color LED 21 arranged in the central portion of the illumination device 10 are both fixed on the substrate 22 so that the optical axis thereof is substantially perpendicular to the lens 12. As shown in FIG. 3, the daylight color LEDs 20 and the light bulb color LEDs 21 are alternately arranged in a matrix.

The lens 12 is made of a light transmissive resin (for example, polycarbonate resin or acrylic resin), and a light diffusion cutting process is applied to the inside of the portion irradiated with light from the daylight color LED 20 and the light bulb color LED 21.
The diffusion film 13 reduces irradiation unevenness of the emitted light of the daylight color LED 20 and the light bulb color LED 21 arranged in a matrix, and improves the color mixing property of the daylight color LED 20 and the light bulb color LED 21.
The control circuit (not shown) is provided with a control circuit that controls lighting states of the daylight color and the light bulb color based on signal input.

Next, the illumination aspect of the illuminating device 10 is demonstrated, referring FIG.
When an electric signal, that is, an electric current is supplied to the daylight color LED 20 and the light bulb color LED 21 provided on the substrate, each LED emits light. Since the daylight color LED 20 and the light bulb color LED 21 are alternately arranged, the color mixing is moderately performed, but the color mixing is promoted by the diffusion effect of the diffusion film 13. The mixed illumination light passes through the lens 12 and is condensed or diffused to irradiate a desired illumination area. In addition, the reflection surface 14 facing the design surface side of the case 11 is subjected to reflection treatment, and the emitted light from the daylight color LED 20 and the light bulb color LED 21 is reflected to the design surface side, so that the emitted light is effectively used for illumination. can do.

Next, an aspect of color mixing control of the illumination device 10 will be described with reference to FIG.
The two curves shown in FIG. 4 indicate the change over time in the illuminance of A: bulb color LED 21 and B: daylight color LED 20, respectively. This change with time indicates a change in lighting state from lighting to bulb color → daylight color → bulb color → light off.

Although the daylight color LED 20 and the light bulb color LED 21 are both turned ON by the signal input from the control circuit, the illuminance of the light bulb color LED 21 rapidly increases, and the illuminance of the light bulb color LED 21 becomes maximum at the time point (1) in FIG. At this time, the color temperature observed outside the illumination device 10 is about 3000K. LEDs are characterized by a very fast response speed to current compared to bulb-type bulbs, but for lighting applications, it is desirable to control the illuminance to gradually increase as shown in the figure rather than to turn on for a moment. .
From the time point (1) in FIG. 4 to the time point (2), control is performed in which the illuminance of the daylight color LED 20 increases in inverse proportion to the illuminance of the light bulb color LED 21 decreasing. As described above, the color temperature can be changed while the illuminance emitted from the illumination device 10 to the outside is kept substantially constant. In addition, the color temperature observed outside the illuminating device 10 at the time of (2) in FIG. 4 is about 4400K.
Control is performed so that the illuminance of the daylight color LED 20 increases in inverse proportion to the decrease in the illuminance of the light bulb color LED 21 from the time point (2) to the time point (3) in FIG. In (3), the illuminance of the daylight color LED 20 is maximum, the light bulb color LED 21 is OFF, and the color temperature observed outside the illumination device 10 is about 5800K. In this control, the color temperature is changed while the illuminance is kept substantially constant.
From (3) to (4) in FIG. 4, control is performed in which the illuminance of the light bulb color LED 21 increases in inverse proportion to the decrease in illuminance of the daylight color LED 20. At this time, the color temperature is changed while the illuminance observed outside is kept almost constant.
From (4) in FIG. 4 to turning off, the daylight color LED 20 and the light bulb color LED 21 are controlled so that the illuminance decreases. It is controlled so that the illuminance is decreased over time so that the light is not extinguished instantaneously as in the case of lighting.

 As described above, when performing control to change the color temperature after the lighting device 10 is turned on, the color temperature is changed almost without changing the illuminance by controlling the increase and decrease of the illuminance to be inversely proportional to each other. Can do.

  The present invention is not limited to the description of the embodiment of the invention. Various modifications may be included in the present invention as long as those skilled in the art can easily conceive without departing from the description of the scope of claims.

FIG. 1 is a side view of a vehicle interior lighting device 10 according to an embodiment of the present invention. 2 is a cross-sectional view taken along the line AA in FIG. FIG. 3 is a front view of the design surface of the vehicle interior lighting device 10. FIG. 4 is a diagram for explaining a change in illumination mode according to a control signal in the vehicular illumination device 10.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Vehicle interior lighting device 11 Case 12 Lens 13 Diffusion film 14 Reflecting surface 20 Daylight color LED
21 Light bulb color LED
22 Substrate

Claims (3)

Equipped with two types of white LED whose emission color is light bulb color and daylight color ,
The difference in color temperature between the two types of white LEDs is 2500K-3500K,
Wherein the illumination by two white LED each emitting light, it has rows and illumination by the two kinds of white LED each color by mixing the emitted light,
In the two types of white LEDs, after the light bulb color white LED is lit, the illuminance peak value is constant regardless of whether it emits a single color or a mixed color, and the illuminance of each white LED increases or decreases. A lighting device installed on a roof portion in a vehicle compartment that is controlled to be in inverse proportion to each other . With the signal input from the control circuit, both the daylight color white LED and the light bulb color white LED are turned on and the illuminance is increased.
The illuminance of the light bulb color white LED is maximum at the first time point, and the color temperature observed outside the illumination device is about 3000K,
From the first time point to the second time point, the illuminance of the daylight color white LED is increased in inverse proportion to the decrease in illuminance of the light bulb color white LED, and the peak value of the illuminance is kept constant. Changing the color temperature to about 4400K;
From the second time point to the third time point, the illuminance of the daylight color white LED is increased in inverse proportion to the decrease in illuminance of the light bulb color white LED, and the peak value of the illuminance is kept constant. While changing the color temperature,
At the third time point, the daylight color white LED has the maximum illuminance and the light bulb color white LED is turned off, and the color temperature is about 5800K.
The lighting device according to claim 1 controlled as described above. 3. The lighting device according to claim 1, wherein a diffusion film that promotes color mixing of light emitted from the two types of LEDs is provided on a light emission side of the two types of white LEDs. 4.