Määritelmä: A color hue with high-medium wavelength that of that portion of the visible spectrum lying between red and yellow, evoked in the human observer by radiant energy with wavelengths of approximately 585 to 620 nanometers.
Määritelmä: A color hue with high wavelength of the long-wave end of the visible spectrum, evoked in the human observer by radiant energy with wavelengths of approximately 630 to 750 nanometers.