Remote lumiphor solid state lighting devices with enhanced light extraction
View Patent ↗Solid state light emitting devices include lumiphor elements that are spatially segregated from electrically activated solid state emitters with an intermediately arranged optical element (including but not limited to a dichroic filter). Curved or faceted optical elements, and curved or faceted reflectors, may be employed. Multiple solid state emitters may be arranged in multiple reflector cups or recesses. Characteristics of optical elements and/or lumiphor elements of such devices may be varied with respect to angular position.
1. A lighting device comprising:
at least one electrically activated solid state emitter;
at least one lumiphoric material spatially segregated from the at least one electrically activated solid state emitter, and arranged to receive at least a portion of emissions from the at least one electrically activated solid state emitter and responsively generate lumiphor emissions;
at least one optical element, selected from the group consisting of optical filters and optical reflectors, arranged between the at least one electrically activated solid state emitter and the at least one lumiphoric material, wherein at least a portion of the at least one optical element is curved or faceted; and
at least one reflector element comprising at least one recess, trough, or cup, and arranged to reflect emissions from the at least one electrically activated solid state emitter toward the at least one optical element;
wherein the at least one optical element is configured to enable passage of a first wavelength range, at least a portion of emissions of the at least one electrically activated solid state emitter being within the first wavelength range;
wherein the at least one optical element is configured to filter or reflect at least a portion of a second wavelength range, at least a portion of the lumiphor emissions being within the second wavelength range, the at least one optical element thereby preventing the at least a portion of the lumiphor emissions from being transmitted toward the at least one electrically activated solid state emitter; and
wherein the first wavelength range differs from the second wavelength range.
2. A lighting device according to claim 1 , wherein the at least one optical element spans a solid angle of less than or equal to 2π steradians.
3. A lighting device according to claim 1 , wherein the at least one optical element comprises a dichroic filter.
4. A lighting device according to claim 1 , wherein at least a portion of the at least one optical element is faceted.
5. A lighting device according to claim 1 , wherein at least a portion of the at least one reflector element is faceted.
6. A lighting device according to claim 1 , wherein the at least one reflector element is specularly reflective.
7. A lighting device according to claim 1 , wherein the at least one lumiphoric material is arranged in a lumiphor element disposed in contact with the at least one optical element.
8. A lighting device according to claim 1 , wherein the at least one electrically activated solid state emitter comprises multiple electrically activated solid state emitters.
9. A lighting device according to claim 1 , wherein the at least one optical element comprises at least one of an interference filter or an interference reflector.
10. A lighting device comprising:
multiple electrically activated solid state emitters;
a lumiphor element spatially segregated from the multiple electrically activated solid state emitters, and arranged to receive at least a portion of emissions from the multiple electrically activated solid state emitters and responsively generate lumiphor emissions;
an optical element, selected from the group consisting of optical filters and optical reflectors, arranged between the multiple electrically activated solid state emitters and the lumiphor element; and
at least one reflector element arranged to reflect emissions from the multiple electrically activated solid state emitters toward the optical element;
wherein the lighting device comprises at least one of the following features (A) or (B):
(A) the optical element comprises a nonzero thickness that varies with respect to angular position along at least a portion of the optical element arranged to receive emissions generated by the multiple electrically activated solid state emitters; or
(B) the lumiphor element comprises at least one of the following characteristics (i) to (iv) that varies with respect to angular position along at least a portion of the lumiphor element arranged to receive emissions transmitted through the optical element: (i) nonzero thickness of the lumiphor element; (ii) nonzero concentration of lumiphoric material; (iii) nonzero amount of lumiphoric material; or (iv) composition of lumiphoric material.
11. A lighting device according to claim 10 , wherein the optical element comprises a nonzero thickness that varies with respect to angular position along at least a portion of the optical element arranged to receive emissions generated by the multiple electrically activated solid state emitters.
12. A lighting device according to claim 10 , wherein the lumiphor element comprises at least one of the following characteristics (i) to (iv) that varies with respect to angular position along at least a portion of the lumiphor element arranged to receive emissions transmitted through the optical element: (i) nonzero thickness of the lumiphor element; (ii) nonzero concentration of lumiphoric material; (iii) nonzero amount of lumiphoric material; or (iv) composition of lumiphoric material.
13. A lighting device according to claim 10 , comprising both features (A) and (B).
14. A lighting device according to claim 10 , wherein at least a portion of the optical element is curved or faceted.
15. A lighting device according to claim 10 , wherein the at least one reflector element comprises multiple recesses or cups arranged to reflect emissions from the multiple electrically activated solid state emitters toward the optical element.
16. A lighting device according to claim 10 , wherein at least a portion of the at least one reflector element is curved or faceted.
17. A lighting device according to claim 10 , wherein the at least one reflector element is specularly reflective.
18. A lighting device according to claim 10 , wherein the optical element comprises a dichroic filter.
19. A lighting device according to claim 10 , further comprising a diffuser arranged to diffuse emissions generated by the multiple electrically activated solid state emitters and the lumiphor element.
20. A lighting device according to claim 10 , wherein:
the optical element is configured to enable passage of a first wavelength range, at least a portion of emissions of the multiple electrically activated solid state emitters being within the first wavelength range;
the optical element is configured to filter or reflect at least a portion of a second wavelength range, at least a portion of the lumiphor emissions being within the second wavelength range, the optical element thereby preventing the at least a portion of the lumiphor emissions from being transmitted toward the multiple electrically activated solid state emitters; and
the first wavelength range differs from the second wavelength range.
21. A lighting device according to claim 10 , wherein the optical element comprises at least one of an interference filter or an interference reflector.
22. A lighting device according to claim 10 , wherein the at least one reflector element comprises at least one recess, trough, or cup.