General lighting with photobiomodulation
A lighting arrangement for general lighting, comprising a first light source 10 adapted to emit a first light substantially only in a first predetermined spectrum in a range from 615 nm to 690 nm, one or more driver circuits adapted to provide a first pulsed driving current to the first light source for producing the first light pulsing with a first peak radiant power in the first predetermined spectrum sufficient to induce a photo-biomodulation response in a human body, and a second light source adapted to emit a second light, the second light source being capable of emitting at least 250 lumens. The pulse characteristics of the first light are such that no visible flicker or stroboscopic effects can be observed by the human eye in the combined light from the first and second light sources during steady-state operation of the lighting arrangement, and the combined light from the first and second light sources has a combined colour point at a distance less than 8 Standard Deviation Color Matching to a black body line in a CIE x,y chromaticity space, and a first radiant power of the first light in the first predetermined spectrum is at least twice a second radiant power of the second light in the second predetermined spectrum during the pulses of the first driving current.
1 . A lighting arrangement for general lighting, comprising:
a first red light source operable to emit a first light that is substantially red light, having a peak emission wavelength in a range from 615 nm to 690 nm;
one or more driver circuits operable to provide a first pulsed driving current to the first light source for producing the first light pulsing with a first peak radiant power;
a second light source operable to emit a second light, the second light source being operable to emit at least 250 lumens;
wherein the lighting arrangement is operable to form a combined light that is substantially white light, from the first light and second light;
wherein the first peak radiant power enables a received power density in a range 0.4-50 mW/cm 2 , measured at a common average distance of between 0.2 m and 5 m from the lighting arrangement or at a distance from the lighting arrangement where the combined light has an illuminance of approximately 500 Lux; and
wherein a first radiant power of the first light is at least twice a second radiant power of the second light during the pulses of the first driving current.
2 . The lighting arrangement of claim 1 , wherein the one or more driver circuits is operable to provide a second driving current to the second light source but not to the first light source, wherein the second driving current is a DC current, an AC current, a rectified AC current, or a pulsed current having a pulse frequency of 2 kHz or more.
3 . The lighting arrangement of claim 1 , wherein an average first radiant power of the first light over a time interval is 40% or less of a sum of the average first radiant power of the first light and an average second radiant power of the second light over the time interval.
4 . The lighting arrangement of claim 1 , wherein the first light source has a peak radiant power in a range from 645 nm to 675 nm.
5 . The lighting arrangement of claim 1 , wherein the second light source comprises a multi-phosphor system having a plurality of phosphors of different emission wavelengths.
6 . The lighting arrangement of claim 1 , wherein a peak emission power of the first light source enables a received power density in a range 1-15 mW/cm 2 , wherein the peak emission power is measured at a common average distance of between 0.2 m and 5 m from the lighting arrangement, or is measured at a distance from the lighting arrangement where the illuminance of the combined light from the first and second light sources is approximately 500 Lux.
7 . The lighting arrangement of claim 1 , wherein the first light source emits at least 3,000 J within 8 hours.
8 . The lighting arrangement of claim 1 , wherein the first light source is operable to deliver a daily dosage (energy per unit area) that is sufficient to induce PBM response in a human body, wherein the dosage is measured at a common average distance of between 0.2 m and 5 m from the lighting arrangement, or is measured at a distance from the lighting arrangement where the illuminance of the combined light from the first and second light sources is approximately 500 Lux.
9 . The lighting arrangement of claim 1 , wherein the first light source is operable to deliver a daily dosage of 0.01-10 J/cm 2 , wherein the daily dosage is measured at a common average distance of between 0.2 m and 5 m from the lighting arrangement; or is measured 30 at a distance where the illuminance of the combined light from the first and second lights sources is approximately 500 Lux.
10 . The lighting arrangement of claim 1 , wherein pulse characteristics of the first light are such that the combined light generated by the first and second light sources together has a luminous flux having a Percent Flicker of not more than 40%, during steady-state operation of the lighting arrangement.
11 . The lighting arrangement of claim 1 , wherein pulse characteristics of the first light are such that the combined light generated by the first and second light sources together has a short term flicker indicator (P st LM) of not more than 1, during steady-state operation of the lighting arrangement.
12 . The lighting arrangement of claim 1 , wherein pulse characteristics of the first light are such that the combined light generated by the first and second light sources together has a Stroboscopic Visibility Measure of not more than 0.4, during steady-state operation of the lighting arrangement.
13 . The lighting arrangement of claim 1 , wherein pulse characteristics of the first light are such that no stroboscopic effects can be observed by the human eye in the combined light from the first and second light sources during steady-state operation of the lighting arrangement.
14 . The lighting arrangement of claim 1 , wherein the combined light from the first and second light sources has a correlated color temperature in the range 1700-6500K.
15 . The lighting arrangement of claim 1 , wherein the combined light from the first and second light sources has a color rendering index in the range 80-100 at a correlated color temperature of about 2700K.
16 . The lighting arrangement of claim 1 , wherein the lighting arrangement is suitable for task lighting.