Led lamps with improved quality of light

An illumination system comprising:

• at least one LED device configured in a housing structure, wherein said at least one LED device comprises an n-type region, a light-emitting active region, and a p-type region, said at least one LED device configured to emit LED light having a peak emission wavelength of about 405nm, said at least one LED device having an external quantum efficiency greater than 45% measured at an ambient temperature of 25° C. and at a current density of 40 A/cm2;
• a wavelength conversion material optically coupled to said at least one LED device and configured to emit converted light;
• a power source electrically coupled to said at least one LED device;
• and
• wherein said illumination system emits emitted light comprising a combination of said LED light and said converted light, said emitted light has a spectral power distribution (SPD) having a correlated color temperature (CCT) and an International Commission on Illumination (CIE) whiteness, said CIE whiteness being at least equal to a reference CIE whiteness of a blackbody radiator with the same CCT, and wherein said SPD has a first power from 380 nm to 800 nm and a second power from 390 nm to about 430 nm, wherein said second power is at least 4% of said first power.