Method to Calculate Melanopic Light Reaching the Retina Depending on the Optical Density of an Aging Crystalline Lens

Lighting studies that take into account the age of inhabitants an area and are related to circadian light difficult find. This study aims simplify a method approximately compute reaching retina based on photopic illuminance corneal plane considering optical density aging crystalline lens. As example this proposed method, calculations were performed with both D65 A standard illuminants, showing how spectral power distribution is modified by lens, mainly at short wavelengths. Due these selective wavelength absorptions aged significant variation in level daylight equivalent melanopic (EDI) present retina. With levels 200 lux plane, variations ranged from 204 EDI 178 for illuminant, 99 101 illuminant observers 10 90, respectively. In work, we aimed greatest possible calculation light, while describing simple protocols easy translate practice. Our results will allow researchers carry out optimized lighting designs photometric perspectives