Lighting systems and methods for providing biologically optimized illumination throughout the day are disclosed. Systems and methods of providing LED light engines and associated illumination spectrums that are both visually appealing, rich in melanopic flux and that reduce blue light hazard exposure are disclosed. Embodiments of the invention relating to specific spectra of illumination containing high or low amounts of melanopic light, spectrally and spatially tunable LED lighting systems, programmed and automated controllers for temporally controlling bio-effective illumination, and dimming circuitry for tuning the spectral output of lighting devices are also disclosed.
