Review and studies on the effect of spectral composition of LED based lighting system over its scotopic-photopic ratio

Light formed through urban morphology and different organism groups: First findings from a systematic review.

“…Existing knowledge related to urban lighting design considers various factors and impacts, e.g., perceived light qualities from a human perspective [56] and physiological and behavioural alterations on species [15]. Few studies concentrate on the interaction between spatial characteristics and lighting [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38]; others focus exclusively on either human vision [39][40][41][42][43][44][45][46][47][48][49][50]62], perception [51][52][53][54]58] or environmental impacts [12-15, 59, 61, 64]. Thus, the overall knowledge on the contribution of spatial characteristics in transforming the light effects in urban contexts, impacting pedestrians and ecology, appears fragmented and not holistically integrated.…”

“…With decreasing light levels, human visual systems tune increasingly to shorter wavelength, and to take advantage of that notion, earlier research suggested strategies to install short wavelength-rich (cool-white appearing) lighting which would allow the lowering of light output and energy consumption [42]. However, the short-wavelength light contributes to skyglow [48], which raises ecological concerns, and, especially under certain weather conditions, decreases visual comfort and performance by hindering dark-light adaptation and producing more glare than visually warmer lighting [49]. Higher brightness does not necessarily support vision, as it can create high contrast ratios with darker surroundings, challenging visual adaptation [50].…”