Solid-state grow-lights for plant cultivation
There is provided a light emitting device for plant cultivation comprising: a broadband blue solid-state light source for generating broadband blue light with a maximum emission wavelength from 420 nm to 495 nm; wherein broadband blue solid-state light source generates blue light from 400 nm to 520 nm having an intensity wavelength spectrum which over a wavelength of at least 40 nm has an intensity that varies by less than 25%, less than 15%, or less than 10%; or from 430 nm to 470 nm or from 450 nm to 465 nm has an intensity that varies by less than 10%.
1 . A light emitting device comprising:
a broadband blue solid-state light source for generating broadband blue light with an emission wavelength from 420 nm to 495 nm;
wherein the broadband blue solid-state light source comprises a InGaN/GaN multiple quantum well LED chip comprising multiple different wavelength quantum wells in its active region for generating multiple narrowband blue to cyan light emissions of different wavelengths and wherein the broadband blue solid-state light source is for generating light having an emission maxima with an intensity which varies less than 15% over a wavelength range of at least 40 nm.
2 . The light emitting device of claim 1 , wherein the emission maxima intensity varies less than 10% over a wavelength range of at least 40 nm.
3 . The light emitting device of claim 1 , wherein the emission maxima intensity varies less than 15% over a wavelength range 430 nm to 470 nm.
4 . The light emitting device of claim 1 , wherein the emission maxima intensity varies less than 10% over a wavelength range 430 nm to 470 nm.
5 . The light emitting device of claim 1 , wherein the broadband blue light is composed of a combination of the multiple narrowband blue to cyan light emissions.
6 . The light emitting device of claim 1 , further comprising a red solid-state light source or red photoluminescence material for generating red light with a peak emission wavelength from 630 nm to 680 nm.
7 . The light emitting device of claim 1 , further comprising a far red solid-state light source or a far red photoluminescence material for generating far red light with a peak emission wavelength from about 630 nm to about 780 nm.
8 . The light emitting device of claim 1 , further comprising at least one of: a green to yellow photoluminescence material for generating green to yellow light with a peak emission wavelength from about 540 nm to about 600 nm; and cyan to red photoluminescence material that generates cyan to red light with a peak emission wavelength from about 500 nm to about 680 nm.
9 . The light emitting device of claim 1 , wherein the broadband blue solid-state light source is for generating broadband blue light having a full width at half maximum of at least 30 nm or from about 30 nm to 80 nm.
10 . The light emitting device of claim 1 , wherein the emission maxima intensity is substantially constant over a wavelength range of at least 40 nm.
11 . The light emitting device of claim 1 , comprising multiple broadband blue solid-state light sources.
12 . The light emitting device of claim 1 , comprising a grow-lamp.