WO2014185226A1

WO2014185226A1 - Multiple color light source device

Info

Publication number: WO2014185226A1
Application number: PCT/JP2014/061244
Authority: WO
Inventors: 杉本　晃三; 康嗣大庭
Original assignee: 矢崎総業株式会社
Priority date: 2013-05-16
Filing date: 2014-04-22
Publication date: 2014-11-20
Also published as: JP2014223844A; DE112014002422T5; CN105230127A

Abstract

Broadband light (Bs) emitted by broadband light emitting diodes (231a,- 231c) which use mass production products with extremely little variation in brightness between individual units for light emitting diode chips is converted to R (red), G (green), B (blue) light (Br, Bg, Bb) by color converters (232a - 232c). The brightness balance for the light (Br, Bg, Bb) is adjusted by a controller (30) by means of duty ratios for pulse signals applied to the broadband light emitting diodes (231a - 231c), and light (B) of a desired emission color is obtained. The brightness balance of the light (Br, Bg, Bb) is determined unambiguously by a combination pattern for the duty ratios of the pulse signals; therefore, the desired emission color (B) can be obtained without fine adjustment operations.

Description

Multi-color light source device

The present invention relates to a multi-color light source device using a light-emitting diode and having a variable emission color.

青色 With the development of blue light emitting diodes, the colors that can be expressed with light emitting diodes have expanded dramatically. Along with this, it has been proposed to use a color light source device using a light-emitting diode with low power consumption and long life in various fields. As an example, there is one proposed to use a full-color LED as a light source of an illumination device that irradiates light to a specific location in a vehicle (Patent Document 1).

JP 2009-90929 A (JP 2009-090929 A)

A full-color LED is configured by mounting RGB light emitting diode chips of RGB on a single substrate, and the light emission drive of each chip is individually duty controlled to adjust the brightness of light of each color. You can change the color.

By the way, the production of full-color LEDs is considerably smaller than broadband LEDs such as white diodes that are mass-produced. For this reason, it is practically difficult to control the quality of the light emitted from each color LED chip in each full-color LED, so that only the LED chips whose light brightness reaches an allowable level are used. Is common. Therefore, even if each color LED chip is driven to emit light with a pulse signal having the same duty ratio, the brightness of the light of each color is not always the same.

Therefore, in order to cause the full color LED to emit light in the correct color, the duty ratio of the pulse signal for matching the emission color in the drive control of the full color LED with the actual emission color, for example, white balance adjustment, is small. It is essential to make adjustments.

In particular, in a vehicle, lighting using a full-color LED may be performed by a pair of left and right sides of a driver seat side and a passenger seat side. In that case, even if the same pattern duty control is performed on the left and right full-color LEDs, if the light emission color differs between the left and right, the commercial value of the vehicle cannot be increased by color illumination.

The present invention has been made in view of the above circumstances, and an object of the present invention is to perform variable adjustment that matches the control color without performing fine adjustment work of the duty ratio of the pulse signal during light emission driving such as white balance adjustment. An object of the present invention is to provide a multi-color light source device using a plurality of light emitting diodes, which can obtain an emission color.

In order to achieve the above object, a multi-color light source device according to an aspect of the present invention controls a plurality of light-emitting diodes individually, thereby changing a light-emission color obtained by mixing the light of each light-emitting diode. A plurality of broadband light emitting diodes that emit broadband light using diode chips of the same standard, and broadband light that each broadband light emitting diode emits, respectively, are different colors from among the three primary colors of light that constitutes the emission color. Each color is a pulse signal with a duty ratio corresponding to the luminance ratio of light before and after color conversion by each color converter determined in advance for each color converted by each color converter A driving unit that drives each broadband light emitting diode corresponding to the converter.

That is, light of a plurality of colors among the three primary colors constituting the emission color is generated by color-converting broadband light such as white light of each broadband light-emitting diode corresponding to each color converter corresponding to each color. .

Here, each broadband light-emitting diode is not a full-color LED in which RGB three-color light-emitting diode chips are mounted on one substrate, but a mass-produced product that emits broadband light using light-emitting diode chips of the same standard is used. . That is, a light-emitting diode chip having extremely small luminance variation between individuals that emit light with the same luminance when driven by a pulse signal having the same duty ratio is used for a broadband light-emitting diode.

Then, each color converter cuts the frequency components of the colors other than the color after the conversion from the frequency components of the broadband light from the broadband light-emitting diode, and converts the broadband light into light of each color.

For this reason, the luminance of the light converted from the original color to each color by the color converter is smaller than the luminance of the broadband light. And the brightness | luminance reduced by color conversion is decided according to the frequency component of the other color cut from the frequency component of broadband light. Therefore, the luminance ratio of light before and after color conversion is individually determined by the color of the light after conversion, that is, the frequency component included in the light after conversion.

That is, the luminance of light of each color after conversion by each color converter is uniquely determined according to the color (frequency component) after conversion. Therefore, in order to obtain the desired emission color, the luminance of each broadband light-emitting diode is calculated in consideration of the luminance ratio before and after the color conversion in order to balance the light of each color after color conversion according to the emission color. Then, each broadband light emitting diode may be driven to emit light by the drive unit with a pulse signal having a duty ratio corresponding thereto.

As a result, the actual emission color composed of the light after color conversion by each color converter is photographed to check the coincidence with the emission color in the drive control, and if necessary, the pulse signal for white balance adjustment etc. There is no need to finely adjust the duty ratio, and a variable emission color that matches the control color can be obtained.

In addition, it is good also as a structure further equipped with the synthetic | combination optical system which guides the light after color conversion by each color converter on the same optical path, mixes it, and radiate | emits it as light of luminescent color. In this case, the multi-color light source device itself additively mixes the light after each color conversion and emits it as a luminescent color.

In addition, the multi-color light source device may emit light of light emission color composed of light after color conversion by each color converter to a plurality of locations of the vehicle.

When the multi-color light source devices at a plurality of locations in the vehicle emit light with the same emission color, in each multi-color light source device, a plurality of broadband light-emitting diodes are driven to emit light with pulse signals having the same combination pattern duty ratio.

In this case, in each multi-color light source device, when the broadband light of each broadband light-emitting diode is color-converted by the corresponding color converter, the luminance of the light decreases at a luminance ratio according to the converted color, The light has a luminance balance corresponding to the emission color, and light of a desired emission color is obtained. Therefore, by simply driving each broadband light emitting diode of each multi-color light source device with a pulse signal having a duty ratio corresponding to the light emission color, the actual light emission colors at each location are compared, and the duty ratio of the pulse signal is reduced. Even if adjustment work is not performed, the emission color of each part can be matched with the emission color in control.

According to the multi-color light source device according to the aspect of the present invention, a variable light emission color that matches the control color can be obtained without performing fine adjustment work of the duty ratio of the pulse signal during light emission driving such as white balance adjustment. Can do.

FIG. 1 is an explanatory diagram illustrating an arrangement of the interior lighting device according to the embodiment. FIG. 2 is a block diagram illustrating a schematic configuration of a multi-color light source device used for the lamp of the interior lighting device according to the embodiment.

Hereinafter, the interior lighting device according to the embodiment will be described with reference to FIGS.

As shown in FIG. 1, a lamp 11 for in-vehicle illumination is provided in the vicinity of the center pillar 7 on the driver's seat 3 side in the vehicle 1, and in the vicinity of the center pillar 9 on the front passenger seat 5 side. A lamp 13 is provided. Each of the

lamps

11 and 13 can change the emission color to an arbitrary color. A multi-color light source device is used as the light source of the

lamps

11 and 13.

The schematic configuration of the multi-color light source device used for the light sources of the

lamps

11 and 13 will be described with reference to the block diagram of FIG. The multi-color light source device 20 according to the embodiment is controlled by the controller 30. The controller 30 is constituted by an auxiliary machine control microcomputer such as an ECU (Electronic Control Unit) mounted on the vehicle 1.

The multi-color light source device 20 includes three driving units 21a-21c and three light emitting units 23a-23c corresponding to the three primary colors of light, R (red), G (green), and B (blue), And a prism 25 that mixes and emits light emitted from the light emitting units 23a to 23c.

Each light emitting unit 23a-23c emits light of each color of R (red), G (green), and B (blue), and includes broadband light emitting diodes 231a-231c and color converters 232a-232c. Each of the broadband light emitting diodes 231a to 231c emits broadband light Bs using a single diode chip. For example, a light emitting diode that emits light in a broadband such as white or milky white (incandescent light bulb color) is used. It suffices if each spectrum includes R (red), G (green), and B (blue).

The brightness of the broadband light Bs emitted from each broadband light emitting diode 231a-231c is determined by the duty ratio of the pulse signal applied as a drive signal by the corresponding driving unit 21a-21c to the broadband light emitting diode 231a-231c. The duty ratio of the pulse signal of each drive unit 21a-21c is determined by the controller 30.

Note that each of the broadband light emitting diodes 231a to 231c is a mass-produced light emitting diode chip that emits light with the same luminance when driven at the same duty ratio and has extremely small variation in luminance between individuals.

The color converters 232a to 232c convert the broadband light Bs of the broadband light emitting diodes 231a to 231c into R (red), G (green), and B (blue) light Br, Bg, and Bb, respectively.

Each of the color converters 232a to 232c has, for example, one that obtains a color after conversion by mixing with the excitation light of the phosphor, one that obtains a color after conversion by a bandpass filter, or after conversion by frequency shift keying (FSK). Various things can be used, such as the one that obtains the color.

The prism 25 is an optical element that guides light incident from the incident portion 25a and emits the light from the light emitting portion 25b. Three incident portions 25a may be provided corresponding to the light beams Br, Bg, Bb of the respective colors from the light emitting portions 23a-23c. The light beams Br, Bg, and Bb incident from the incident unit 25a are guided to the same optical path by refraction and reflection inside the prism 25. The light beams Br, Bg, and Bb of the respective colors are mixed on the same optical path, and the mixed color light B is emitted from the emission unit 25b to the outside of the prism 25.

Next, an operation (action) in each of the light emitting units 23a-23c of the multi-color light source device 20 according to the embodiment will be described.

The light-emitting diode chips used in the respective broadband light-emitting diodes 231a to 231c are mass-produced products of the same standard, emit light with the same luminance when driven at the same duty ratio, and have extremely small luminance variations among individuals. Therefore, the brightness of the broadband light Bs of each broadband light emitting diode 231a-231c driven to emit light by the pulse signal from each drive unit 21a-21c is a value corresponding to the duty ratio of the pulse signal.

Further, in the color converters 232a-232c, the frequency components of the color except R (red), the frequency components of the color excluding G (green), and the B (blue) from the frequency components of the broadband light Bs of the broadband light emitting diodes 231a-231c. The frequency components of colors other than) are cut off. As a result, the broadband light Bs is converted into the light beams Br, Bg, and Bb of R (red), G (green), and B (blue), respectively.

For this reason, the luminances of the light Br, Bg, and Bb that have been converted into the R (red), G (green), and B (blue) colors by the color converters 232a to 232c are lower than the luminance of the broadband light Bs. . The luminance decreased by color conversion depends on the frequency components of colors other than R (red), colors other than G (green), and colors other than B (blue) that are cut from the frequency components of the broadband light Bs. Each is determined.

Therefore, the luminance ratio of light before and after color conversion to R (red), G (green), and B (blue) by the color converters 232a to 232c is R (red), G (green), and B (blue). ) Individually determined by the frequency components included in each color light Br, Bg, Bb. In other words, the luminance ratio of the light before and after the color conversion is individually determined by the frequency components of colors other than the R (red), G (green), and B (blue) colors cut from the frequency components of the broadband light Bs at the time of color conversion. Determined.

As described above, the broadband light Bs of each of the broadband light emitting diodes 231a to 231c has a luminance corresponding to the duty ratio of the pulse signal from each of the drive units 21a to 21c, and the luminance of the light before and after color conversion depending on the color after conversion. The ratio is determined. For this reason, the brightness of each color light Br, Bg, Bb after the conversion by each color converter 232a-232c depends on the duty ratio of the pulse signal applied to each corresponding broadband light emitting diode 231a-231c and the color ( Frequency).

In order to obtain the light B having a desired emission color by mixing the light-converted R (red), G (green), and B (blue) light Br, Bg, Bb, the light Br, Bg, Bb needs to have a luminance balance corresponding to each emission color.

Therefore, in the multi-color light source device 20 of the present embodiment, the controller 30 causes the light Br, Bg, Bb of R (red), G (green), and B (blue) to have a luminance balance according to the emission color. The luminance of each broadband light emitting diode 231a-231c is calculated in consideration of the luminance ratio before and after color conversion by each color converter 232a-232c.

Then, the controller 30 outputs a pulse signal having a duty ratio corresponding to the calculated luminance from each driving unit 21a-21c to each corresponding broadband light emitting diode 231a-231c. Thereby, the light Br, Bg, Bb of each color of R (red), G (green), and B (blue) is emitted from each of the light emitting units 23a-23c with a luminance balance corresponding to the emission color.

Therefore, the controller 30 changes the luminance balance of the light Br, Bg, and Bb of R (red), G (green), and B (blue) through the duty ratio of the pulse signal output from each driving unit 21a-21c. Thus, the color of the light B emitted from the prism 25 can be arbitrarily changed.

Thus, in the multi-color light source device 20 according to the embodiment, the light Br, Bg, Bb of R (red), G (green), and B (blue) is generated by color conversion from the broadband light Bs, and the broadband light As the light emitting diode chips of the respective broadband light emitting diodes 231a to 231c that emit Bs, mass-produced products having extremely small luminance variations among individuals were used.

For this reason, R (red), G (green), and B (blue) light Br, Bg, and Bb are used as pulse signals to be applied from the driving units 21a to 21c to the corresponding broadband light emitting diodes 231a to 231c. By setting the duty ratio to a luminance balance according to the emission color, the color of the light B emitted from the prism 25 after mixing can be surely set to a desired emission color.

As a result, the light B emitted from the prism 25 is actually captured by the camera, and the emission color on the drive control corresponding to the duty ratio of the pulse signal of each of the drive units 21a-21c and the emitted light from the prism 25. Further, it is possible to eliminate the need to confirm the coincidence with the actual color of the light B. That is, the fine adjustment of the duty ratio of the pulse signal such as white balance adjustment is performed only by appropriately setting the duty ratio of the pulse signal applied to each broadband light emitting diode 231a-231c by each of the driving units 21a-21c. Even if it is not, the desired color light B can be actually obtained.

In the present embodiment, in each multi-color light source device 20 used for the

lamps

11 and 13 of the left and

right center pillars

7 and 9 of the vehicle 1, the controller 30 causes each broadband light emitting diode 231a- 231c is driven to emit light. Therefore, when each broadband light emitting diode 231a-231c of each multi-color light source device 20 is driven to emit light with a pulse signal having the same duty ratio pattern, light of the same emission color is emitted from each prism 25.

At this time, in each of the multi-color

light source devices

20 and 20, each broadband light-emitting diode 231a-231c uses a mass-produced light-emitting diode chip with extremely small luminance variation between individuals. Accordingly, in each of the multi-color

light source devices

20 and 20, when each of the broadband light emitting diodes 231a to 231c is driven to emit light with the same combination of duty ratio pattern pulse signals, the light emitted from each of the light emitting units 23a to 23c It becomes the same luminescent color with no color difference.

For this reason, in a plurality (two in the present embodiment) of multi-color light source devices 20, each broadband light emitting diode 231a-231c is driven to emit light with a pulse signal having the same combination pattern of duty ratios, so that the duty ratio of the pulse signal is set. Even without fine adjustment, the emission color mixed by the prism 25 can be matched with the desired emission color.

In this embodiment, a configuration in which R (red), G (green), and B (blue) light Br, Bg, and Bb are mixed by the prism 25 to obtain light B of an arbitrary color is taken as an example. explained. However, one of R (red), G (green), and B (blue) may be omitted, replaced with light of another color (for example, milky white (incandescent light bulb color)), R (red), G ( The color can be arbitrarily changed, for example, by adding other colors to green and B (blue) and mixing four or more lights to obtain a desired emission color.

In the present embodiment, the case where the multi-color light source device 20 is used as the light source of the

lamps

11 and 13 near the left and

right center pillars

7 and 9 of the vehicle 1 has been described. However, the present invention can also be applied to a multi-color light source device used alone or in combination of three or more.

Further, in the present embodiment, the case where the multi-color light source device 20 includes the prism 25 has been described. However, the multi-color light source device is configured by the drive units 21a-21c and the light-emitting units 23a-23c, and the prism 25 is separated. Alternatively, a multi-color light source device may be configured including the controller 30 regardless of the presence or absence of the prism 25.

The present invention is extremely useful for a multi-color light source device that arbitrarily changes the emission color by individually driving and controlling a plurality of broadband light emitting diodes.

Claims

A multi-color light source device that changes emission color by mixing light of each light emitting diode by individually controlling driving of a plurality of light emitting diodes,
A plurality of broadband light emitting diodes that emit broadband light using diode chips of the same standard;
A plurality of color converters for respectively converting the broadband light emitted by each of the broadband light emitting diodes into light of different colors in the three primary colors of the light constituting the emission color;
Each broadband light emitting diode corresponding to each color converter is a pulse signal having a duty ratio corresponding to a luminance ratio of light before and after color conversion by each color converter, which is predetermined for each color after conversion by each color converter. A drive unit for driving each;
A multi-color light source device comprising:
The multi-color light source device according to claim 1,
A multi-color light source device further comprising a combining optical system that guides light after color conversion by each of the color converters onto the same optical path, mixes the light, and emits it as light of the emission color.
The multi-color light source device according to claim 1 or 2,
A multi-color light source device that emits light of the emission color composed of light after color conversion by each color converter to a plurality of locations of a vehicle.