LIGHTING APPARATUS

• US 20120008318A1
• Filed: 04/27/2010
• Published: 01/12/2012
• Est. Priority Date: 04/27/2009
• Status: Abandoned Application

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Lighting & Technology Corporation (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Lighting & Technology Corporation (Toshiba Corporation)
• Inventors: Ishiwata, Tomoko, Mita, Kazutoshi, Kawano, Hitoshi, Yashiro, Kazunori, Uchino, Katsusuke, Yamazaki, Isao
• Application Number:
  US13/256,649
• Publication Number:
  US 20120008318A1
• Time in Patent Office: Days
• US Class Current: 362/231
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/22 using optical feedback

Abstract

A lighting apparatus includes a red LED; a green LED; a blue LED; and a white LED made up of a blue light-emitting element and a yellow phosphor, wherein the red LED, the green LED, the blue LED, and the white LED generate 26 to 38%, 35 to 50%, 0 to 2%, and 12 to 33% of light, respectively, and white light obtained by additive color mixing of light from the red, green, blue, and white LEDs has a correlated color temperature of 2800 K or more to less than 3500 K, a deviation of 0.02 or below in absolute value, and a color gamut area ratio of 120% or more to 140% or less. Consequently, the lighting apparatus can radiate an illuminating light which makes colors look vivid.

Claims

1. A lighting apparatus comprising:

a red LED which has a peak wavelength of emission spectrum in a range of 610 to 630 nm and a full width at half maximum in a range of 10 to 20 nm;

a green LED which has a peak wavelength of emission spectrum in a range of 500 to 520 nm and a full width at half maximum in a range of 20 to 30 nm;

a blue LED which has a peak wavelength of emission spectrum in a range of 450 to 470 nm and a full width at half maximum in a range of 10 to 20 nm; and

a white LED made up of a blue light-emitting element and a yellow phosphor,

wherein the red LED generates light at a flux ratio of between 26 and 38%;

the green LED generates light at a flux ratio of between 35 and 50%;

the blue LED generates light at a flux ratio of between 0 and 2%;

the white LED generates light at a flux ratio of between 12 and 33%;

white light is obtained by additive color mixing of light from the red, green, blue, and white LEDs; and

the white light has a correlated color temperature of 2800 K or more to less than 3500 K, a deviation of 0.02 or below in absolute value, and a color gamut area ratio of 120% or more to 140% or less when the white light is used as a test light, where the color gamut area ratio is a ratio between a color gamut area formed by connecting eight points in chromaticity coordinates when JIS color rendering test colors No. 1 to No. 8 are lighted by the test light and a color gamut area formed by connecting eight points in the chromaticity coordinates when the JIS color rendering test colors No. 1 to No. 8 are lighted by a reference light.

2. The lighting apparatus according to claim 1, wherein:

the red LED generates light at a flux ratio of between 18 and 31%;

the green LED generates light at a flux ratio of between 28 and 46%;

the blue LED generates light at a flux ratio of between 0 and 2%;

the white LED generates light at a flux ratio of between 23 and 52%;

white light is obtained by additive color mixing of light from the red, green, blue, and white LEDs; and

the white light has a correlated color temperature of 3500 K or more to less than 5000 K, a deviation of 0.02 or below in absolute value, and a color gamut area ratio of 120% or more to 140% or less when the white light is used as the test light.

3. The lighting apparatus according to claim 1, wherein:

the red LED generates light at a flux ratio of between 18 and 30%;

the green LED generates light at a flux ratio of between 28 and 57%;

the blue LED generates light at a flux ratio of between 0 and 3%;

the white LED generates light at a flux ratio of between 15 and 52%;

white light is obtained by additive color mixing of light from the red, green, blue, and white LEDs; and

the white light has a correlated color temperature of 5000 K or more to 10000 K or less, a deviation of 0.02 or below in absolute value, and a color gamut area ratio of 110% or more to 140% or less when the white light is used as the test light.

4. The lighting apparatus according to claim 1, wherein:

a plurality of the red, green, blue, and white LEDs are provided; and

out of the red, green, blue, and white LEDs, LEDs complementary to each other are placed adjacent to each other and LEDs of a same type are arranged point-symmetrically.

5. The lighting apparatus according to claim 1, further comprising:

an RGB sensor configured to detect a red component, a green component, and a blue component of incident light;

a diffuser plate configured to transmit and reflect light from the red, green, blue, and white LEDs;

a light shielding member configured to block direct light from the red, green, blue, and white LEDs and give mixed light from the diffuser plate to the RGB sensor; and

a control unit configured to keep flux ratios of the light from the red, green, blue, and white LEDs constant based on detection results produced by the ROB sensor.

13. The lighting apparatus according to claim 1, wherein:

white light is obtained by additive color mixing of light from the red, green, blue, and white LEDs; and

the white light has a color gamut area ratio of 105% or more to 140% or less when the white light is used as the test light and has a chroma difference of 4 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 9 lighted by the illuminating light radiated from the light source or by the reference light.

14. The lighting apparatus according to claim 2, wherein:

white light is obtained by additive color mixing of light from the red, green, blue, and white LEDs; and

the white light has a color gamut area ratio of 105% or more to 140% or less when the white light is used as the test light and has a chroma difference of 4 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 9 lighted by the illuminating light radiated from the light source or by the reference light.

15. The lighting apparatus according to claim 3, wherein:

white light is obtained by additive color mixing of light from the red, green, blue, and white LEDs; and

the white light has a color gamut area ratio of 105% or more to 140% or less when the white light is used as the test light and has a chroma difference of 4 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 9 lighted by the illuminating light radiated from the light source or by the reference light.

16. The lighting apparatus according to claim 1, wherein:

white light is obtained by additive color mixing of light from the red, green, blue, and white LEDs; and

the white light has a color gamut area ratio of 105% or more to 140% or less when the white light is used as the test light and has a chroma difference of 3 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 11 lighted by the illuminating light radiated from the light source or by the reference light.

17. The lighting apparatus according to claim 2, wherein:

white light is obtained by additive color mixing of light from the red, green, blue, and white LEDs; and

the white light has a color gamut area ratio of 105% or more to 140% or less when the white light is used as the test light and has a chroma difference of 3 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 11 lighted by the illuminating light radiated from the light source or by the reference light.

18. The lighting apparatus according to claim 3, wherein:

white light is obtained by additive color mixing of light from the red, green, blue, and white LEDs;

the white light has a color gamut area ratio of 105% or more to 140% or less when the white light is used as the test light and has a chroma difference of 2 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 11 lighted by the illuminating light radiated from the light source or by the reference light.

19. The lighting apparatus according to claim 1, further comprising:

an apparatus body in which the red LED, the green LED, the blue LED, and the white LED are disposed; and

a lighting control device configured to control an ON state or an OFF state of the red LED, the green LED, the blue LED, and the white LED.

6. A lighting apparatus, comprising:

a light source configured to radiate an illuminating light by additively mixing color lights from a red LED, a green LED, a blue LED, and a white LED, wherein

the light source has a color gamut area ratio of 105% or more to 140% or less when the illuminating light radiated from the light source is used as a test light, has a chroma difference of 4 or above between the illuminating light and a reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 9 lighted by the illuminating light radiated from the light source or by the reference light, has a correlated color temperature of 2800 K or more to less than 5000 K, and has a deviation duv of 0.02 or below in absolute value, where the color gamut area ratio is a ratio between a color gamut area formed by connecting four points in chromaticity coordinates when JIS color rendering test colors No. 9 to No. 12 are lighted by the test light and a color gamut area formed by connecting four points in the chromaticity coordinates when the JIS color rendering test colors No. 9 to No. 12 are lighted by the reference light.

7. The lighting apparatus according to claim 6, wherein the light source has a color gamut area ratio of 105% or more to 140% or less when the illuminating light radiated from the light source is used as the test light, has a chroma difference of 3 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 11 lighted by the illuminating light radiated from the light source or by the reference light, has a correlated color temperature of 2800 K or more to less than 3500 K, and has a deviation duv of 0.02 or below in absolute value.

8. The lighting apparatus according to claim 6, wherein the light source has a color gamut area ratio of 105% or more to 140% or less when the illuminating light radiated from the light source is used as the test light, has a chroma difference of 2 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 11 lighted by the illuminating light radiated from the light source or by the reference light, has a correlated color temperature of 5000 K or above, and has a deviation duv of 0.02 or below in absolute value.

9. The lighting apparatus according to claim 6, wherein the light source has a color gamut area ratio of 105% or more to 140% or less when the illuminating light radiated from the light source is used as the test light, has an area of 0°

to 45°

or an area of 315°

to 360°

in terms of an ab hue angle (hab) (No.

     9) of first chromaticity on an a*b* chromaticity coordinate diagram when the first chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 9 lighted by the illuminating light radiated from the light source, has an area of 135°

to 225°

in terms of an ab hue angle (hab) (No.

     11) of second chromaticity on the a*b* chromaticity coordinate diagram when the second chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 11 lighted by the illuminating light, has a correlated color temperature of 2800 K or more to less than 5000 K, and has a deviation duv of 0.02 or below in absolute value.

10. The lighting apparatus according to claim 6, wherein the light source has a color gamut area ratio of 105% or more to 140% or less when the illuminating light radiated from the light source is used as the test light, has a chroma difference of 4 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 9 lighted by the illuminating light radiated from the light source or by the reference light, has a correlated color temperature of 2800 K or more to less than 5000 K, has a deviation duv of 0.02 or below in absolute value, and has an area of 0°

to 45°

or an area of 315°

to 360°

in terms of an ab hue angle (hab) (No.

     9) of first chromaticity on the a*b* chromaticity coordinate diagram when the first chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 9 lighted by the illuminating light.

11. The lighting apparatus according to claim 6, wherein the light source has a color gamut area ratio of 105% or more to 140% or less when the illuminating light radiated from the light source is used as the test light, has a chroma difference of 3 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 11 lighted by the illuminating light radiated from the light source or by the reference light, has a correlated color temperature of 2800 K or more to less than 3500 K, has a deviation duv of 0.02 or below in absolute value, and has an area of 135°

to 225°

in terms of an ab hue angle (hab) (No.

     11) of second chromaticity on the a*b* chromaticity coordinate diagram when the second chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 11 lighted by the illuminating light.

12. The lighting apparatus according to claim 6, wherein the light source has a color gamut area ratio of 105% or more to 140% or less when the illuminating light radiated from the light source is used as the test light, has a chroma difference of 2 or above between the illuminating light and the reference light on an a*b* chromaticity coordinate diagram when chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 11 lighted by the illuminating light radiated from the light source or by the reference light, has a correlated color temperature of 5000 K, has a deviation duv of 0.02 or below in absolute value, and has an area of 135°

to 225°

in terms of an ab hue angle (hab) (No.

     11) of second chromaticity on the a*b* chromaticity coordinate diagram when the second chromaticity is plotted on the a*b* chromaticity coordinate diagram with a color chip of JIS color rendering test color No. 11 lighted by the illuminating light.