Light sources adapted to spectral sensitivity of diurnal avians and humans
Various apparatus and associated methods involve a light source that provides light at wavelengths that substantially correlate to local maxima in the spectral sensitivity of a diurnal avian. In an illustrative example, the light source may output light primarily in wavelength bands that are not substantially absorbed by colored oil droplets and/or visual pigment in at least one type of cone in the eye of a diurnal avian. In some embodiments, the light source may include a light-emitting diode (LED) light source. Exemplary light sources may output spectral components to illuminate diurnal avians with local maxima of intensity at wavelengths that substantially correspond to local maxima in a spectral sensitivity visual response characteristic of the diurnal avians.
1. A method of illuminating diurnal avians with artificial light sources, the method comprising: supplying a first light having a first spectral content between 380 nm (nanometers) and 780 nm to a substantially enclosed habitat for diurnal avians; supplying a second light having a second spectral content between 380 nm and 780 nm and having at least one local maximum in relative intensity at a wavelength within 15 nm of a wavelength at which a predetermined characteristic visual spectral response of the diurnal avian has a local maximum to a substantially enclosed habitat for diurnal avians; and wherein at least one local maximum in relative intensity of the second spectral content is above the median relative intensity of local maxima of the second spectral content.
2. The method of claim 1 , wherein the at least one local maximum in relative intensity of the second spectral content is among the three highest relative intensities of local maxima of the second spectral content for wavelengths between 380 nm and 780 nm.
3. The method of claim 1 , wherein the at least one local maximum in relative intensity of the second spectral content is among the four highest relative intensities of local maxima of the second spectral content for wavelengths between 380 nm and 780 nm.
4. The method of claim 1 , wherein the first spectral content comprises a substantially different relative intensity characteristic than the second spectral content.
5. The method of claim 1 , wherein the at least one local maximum in relative intensity of the second spectral content is between 450 nm and 510 nm.
6. The method of claim 1 , wherein the at least one local maximum in relative intensity of the second spectral content is between 590 nm and 620 nm.
7. The method of claim 1 , wherein the at least one local maximum in relative intensity of the second spectral content is below 400 nm.
8. The method of claim 1 , wherein the second spectral content has at least one local maximum in relative intensity at a wavelength below 400 nm and that is within 15 nm of the wavelength at which a predetermined characteristic visual spectral response of the diurnal avian has a local maximum.
9. The method of claim 1 , wherein the at least one local maximum in relative intensity is at a wavelength within about 10 nm of a wavelength at which the predetermined characteristic visual spectral response of the diurnal avian has the local maximum.
10. The method of claim 1 , wherein the local maxima of the predetermined characteristic visual spectral response of the diurnal avian correspond to the spectral absorbance characteristics of oil droplets in the diurnal avian's eyes.
11. The method of claim 1 , wherein converting the first light to a second light comprises emitting the second spectral content with a substantially red content in response to the first spectral content comprising a substantially blue content.
12. The method of claim 1 , wherein the second spectral content further comprises having at least two local maxima in relative intensity, each local maxima being at a wavelength within about 25 nm of a first and a second respective wavelengths at which the predetermined characteristic visual spectral response of the diurnal avian has distinct local maxima.
13. The method of claim 12 , wherein the at least two local maxima in relative intensity of the second spectral content are among the three highest relative intensities of local maxima of the second spectral content for wavelengths between 380 nm and 780 nm.
14. The method of claim 1 , wherein the second spectral content further comprises having at least three local maximum in relative intensity, each local maxima being at a wavelength within about 30 nm of a first and a second respective wavelengths at which the predetermined characteristic visual spectral response of the diurnal avian has distinct local maxima.
15. The method of claim 14 , wherein the at least three local maxima in relative intensity of the second spectral content are among the four highest relative intensities of local maxima of the second spectral content for wavelengths between 380 nm and 780 nm.
16. A spectrally adapted illumination apparatus for illuminating diurnal avians, the apparatus comprising: a first light source to generate a first light having a first spectral content between 380 nm (nanometers) and 780 nm to a substantially enclosed habitat for diurnal avians; a second light source to generate a second spectral content having at least one local maximum in relative intensity at a wavelength within 15 nm of a wavelength at which a predetermined characteristic visual spectral response of the diurnal avian has a local maximum to a substantially enclosed habitat for diurnal avians; and, a conditioning circuit to selectively supply current to both the first and second light sources.
17. The apparatus of claim 16 , wherein the at least one local maximum in relative intensity of the second spectral content is between 450 nm and 510 nm.
18. The apparatus of claim 16 , wherein the at least one local maximum in relative intensity of the second spectral content is between 590 nm and 620 nm.
19. The apparatus of claim 16 , wherein the at least one local maximum in relative intensity of the second spectral content is below 400 nm.