LIGHT-EMITTING DEVICE, LIGHTING DEVICE, AND OPTICAL MEMBER

• US 20200132259A1
• Filed: 10/30/2019
• Published: 04/30/2020
• Est. Priority Date: 10/31/2018
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: SHIMA, Kohei, KAWANO, Yohei, ASANO, Akira
• Granted Patent: US 11,047,549 B2
• Time in Patent Office: Days
• CPC Class Codes: F21K 9/237 Details of housings or cases, i.e. the parts between the light-generating element and the bases; Arrangement of components within housings or cases F21K9/238 takes precedence
• CPC Class Codes: F21K 9/278 Arrangement or mounting of circuit elements integrated in the light source
• CPC Class Codes: F21K 9/61 using light guides
• CPC Class Codes: F21S 8/04 intended only for mounting on a ceiling or the like overhead structures F21S8/02 takes precedence; details of ceiling bases F21V21/03
• CPC Class Codes: F21V 23/04 the elements being switches safety devices F21V25/00
• CPC Class Codes: F21V 5/045 the lens having discontinuous faces, e.g. Fresnel lenses
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21V 7/04 Optical design
• CPC Class Codes: F21Y 2105/18 annular; polygonal other than square or rectangular, e.g. for spotlights or for generating an axially symmetrical light beam
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0066 in the form of an LED array
• CPC Class Codes: G02B 27/425 in illumination systems mask illumination systems in photolithographic systems G03F7/70158
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/40 Details of LED load circuits

Abstract

A light-emitting device includes an optical member including first and second light emitting elements, first and second light condenser portions, and a light guide portion.

The first light condenser portion is disposed at a position corresponding to the first light-emitting element, and condenses a portion of light emitted from the first light-emitting element.

The second light condenser portion surrounds the first light condenser portion, and condenses a portion of the light that is not incident to the first light condenser portion among the light emitted from the first light-emitting element.

The light guide portion is disposed at a periphery of the second light condenser portion and at a position corresponding to the second light-emitting element, and guides light emitted from the second light-emitting element by causing total reflection in an interior of the light guide portion.

A full width at half maximum of light exiting from the light guide portion is larger than a full width at half maximum of light exiting from the first light condenser portion.

Claims

1. A light-emitting device, comprising:

one or more first light-emitting elements;

one or more second light-emitting elements; and

an optical member comprising;

a first light condenser portion disposed at a position corresponding to the one or more first light-emitting elements, the first light condenser portion condensing a portion of light emitted from the one or more first light-emitting elements;

a second light condenser portion surrounding the first light condenser portion, the second light condenser portion condensing a portion of the light that is not incident to the first light condenser portion among the light emitted from the one or more first light-emitting elements; and

a first light guide portion disposed at a periphery of the second light condenser portion and at a position corresponding to the one or more second light-emitting elements, the first light guide portion guiding light emitted from the one or more second light-emitting elements by causing total reflection in an interior of the first light guide portion,

wherein a full width at half maximum of light exiting from the first light guide portion is larger than a full width at half maximum of light exiting from the first light condenser portion.

2. The light-emitting device according to claim 1, wherein the first light guide portion is a transparent member, and diffuses and outputs the light emitted from the one or more second light-emitting elements.

3. The light-emitting device according to claim 1, wherein the second light condenser portion is a transparent member having an inner surface and an outer surface, the inner surface being a surface on which light is incident, the outer surface causing total reflection of at least a portion of the light entering from the inner surface.

4. The light-emitting device according to claim 1, further comprising:

one or more third light-emitting elements; and

a second light guide portion surrounding the first light guide portion and disposed at a position corresponding to the one or more third light-emitting elements, the second light guide portion guiding a portion of light incident on a third light incident region,

wherein a full width at half maximum of light exiting from the second light guide portion is larger than the full width at half maximum of the light exiting from the first light guide portion.

5. The light-emitting device according to claim 1, wherein

the first light condenser portion is a convex lens, and

the first light guide portion is a transparent member arranged in an annual configuration so as to surround the convex lens.

6. The light-emitting device according to claim 5, wherein a minimum curvature radius of the convex lens is not less than 0.3 mm and not more than 13 mm.

7. The light-emitting device according to claim 1, wherein a color temperature of the light emitted from the one or more second light-emitting elements is different from a color temperature of the light emitted from the one or more first light-emitting elements.

8. The light-emitting device according to claim 1, wherein

the one or more first-light emitting elements are plural first light-emitting elements that are disposed in a first region,

the one or more second light-emitting elements are plural second light-emitting elements that are disposed in a second region so as to surround the first region,

a color temperature of the light emitted from the plural second light-emitting elements is different from a color temperature of the light emitted from the plural first light-emitting elements,

a first circuit including the plural first light-emitting elements and a second circuit including the plural second light-emitting elements are connected in parallel to each other, and

a number of stages of the plural first light-emitting elements connected in series in the first circuit is less than a number of stages of the plural second light-emitting elements connected in series in the second circuit.

9. The light-emitting device according to claim 8, further comprising:

two or more of the first light-emitting elements, and

the two or more first light-emitting elements are disposed in the second region.

10. The light-emitting device according to claim 8, further comprising a first resistance element connected to the one or more first light-emitting elements in the first circuit in series connection.

11. The light-emitting device according to claim 8, further comprising:

one or more third light-emitting elements disposed in the second region; and

one or more fourth light-emitting elements disposed in the second region,

a color temperature of the light emitted from the plural first light-emitting elements, a color temperature of the light emitted from the plural second light-emitting elements, a color temperature of light emitted from the one or more third light-emitting elements, and a color temperature of light emitted from the one or more fourth light-emitting elements being different from each other.

12. The light-emitting device according to claim 11, wherein

a third circuit including plural third light-emitting elements and a fourth circuit including plural fourth light-emitting elements are connected in parallel to each other, and

a number of stages of the plural third light-emitting elements connected in series in the third circuit is less than a number of stages of the plural fourth light-emitting elements connected in series in the fourth circuit.

13. The light-emitting device according to claim 12, further comprising a second resistance element connected to the plural third light-emitting elements in the third circuit in series connection.

14. The light-emitting device according to claim 11, further comprising a second light guide portion surrounding the second region to guide light entering from a third region, wherein,

a full width at half maximum of light emitted from the second light guide portion is larger than the full width at half maximum of the light emitted from the first light guide portion,

two or more of the third light-emitting elements and two or more of the fourth light-emitting elements are provided,

wherein the light-emitting device further comprises plural third light-emitting element and the plural fourth light-emitting element disposed also in the third region.

15. The light-emitting device according to claim 1, wherein a color of light emitted from the light-emitting device can be changed to follow blackbody radiation.

21. A lighting device, comprising:

the light-emitting device according to claim 1;

a diffuser plate disposed at a position where light emitted from the light-emitting device is incident; and

a cover member covering lateral surfaces of the light-emitting device and the diffuser plate.

16. A light-emitting device, comprising:

an optical member comprising;

a first light condenser portion having a convex lens;

a second light condenser portion having an inner surface and an outer surface being curved outward as approaching a light exiting surface, while surrounding the first light condenser portion;

a first light guide portion having a tubular configuration surrounding a periphery of the second light condenser portion in an annular configuration;

one or more first light-emitting elements disposed at a position corresponding to the first light condenser portion; and

one or more second light-emitting elements disposed at a position corresponding to the first light guide portion.

17. The light-emitting device according to claim 16, wherein a minimum curvature radius of the outer surface is not less than 0.6 mm and not more than 28 mm.

18. The light-emitting device according to claim 16, further comprising:

a second light guide portion having a tubular configuration surrounding a periphery of the first light guide portion in an annular configuration; and

one or more third light-emitting elements disposed at a position corresponding to the second light guide portion,

wherein the first light guide portion and the second light guide portion are each a transparent member, and are each a trapezoidal configuration in a plane perpendicular to a light exiting surface as seen from a cross-sectional view, and

a taper angle of the second light guide portion being smaller than a taper angle of the first light guide portion.

19. The light-emitting device according to claim 18, wherein a taper ratio of the first light guide portion is greater than 0 and not more than 0.54.

20. The light-emitting device according to claim 18, wherein a taper ratio of the second light guide portion is not less than 0 and not more than 0.1.

22. An optical member, comprising:

a first light condenser portion condensing light incident on a first light incident region;

a second light condenser portion surrounding the first light condenser portion, the second light condenser portion condensing a portion of the light that is not incident to the first light condenser portion and outputting from a position facing the first light incident region; and

a first light guide portion surrounding the second light condenser portion, and guiding light emitted from the one or more second light-emitting elements by causing total reflection in an interior of the first light guide portion,

wherein a full width at half maximum of light exiting from the first light guide portion is larger than a full width at half maximum of light exiting from the first light condenser portion.

23. The optical member according to claim 22, wherein the first light condenser portion, the second light condenser portion, and the first light guide portion are formed as one transparent body.

24. An optical member, comprising:

a first light condenser portion;

a second light condenser portion having an inner surface and an outer surface being curved outward as approaching a light exiting surface, the second light condenser portion surrounding the first light condenser portion; and

a first light guide portion having a tubular configuration surrounding a periphery of the second light condenser portion in an annular configuration.

25. The optical member according to claim 24, wherein the first light condenser portion, the second light condenser portion, and the first light guide portion are formed as one transparent body.

26. A light-emitting circuit, comprising:

a plurality of first light-emitting elements disposed in a first region; and

a plurality of second light-emitting elements surrounding the first region,

a color temperature of light emitted from the plurality of second light-emitting elements being different from a color temperature of light emitted from the plurality of first light-emitting elements,

a first circuit including the plurality of first light-emitting elements and a second circuit including the plurality of second light-emitting elements are connected in parallel to each other,

a number of stages of the plurality of first light-emitting elements connected in series in the first circuit being less than a number of stages of the plurality of second light-emitting elements connected in series in the second circuit.

27. The light-emitting circuit according to claim 26, further comprising a first resistance element connected to the plurality of first light-emitting elements in series connection in the first circuit.

28. The light-emitting circuit according to claim 26, further comprising:

one or more third light-emitting elements; and

one or more fourth light-emitting elements,

wherein the color temperature of the light emitted from the plurality of first light-emitting elements, the color temperature of the light emitted from the plurality of second light-emitting elements, a color temperature of light emitted from the plurality of third light-emitting elements, and a color temperature of light emitted from the plurality of fourth light-emitting elements being different from each other,

a third circuit including the one or more third light-emitting elements and a fourth circuit including the one or more fourth light-emitting elements are connected in parallel to each other,

a number of stages of the plurality of third light-emitting elements connected in series in the third circuit being less than a number of stages of the plurality of fourth light-emitting elements connected in series in the fourth circuit.