Spectral optimization of healthy laser-based displays applied for people of different age groups

• A spectral optimization method for LBDs is proposed for different age groups. • The method uses a Gaussian spectral model and GA with GC and CCT constraints. • Optimal SPDs are identified to minimize or maximize MELR. • MELR is found to decrease with age and increase with CCT. • Four-primary LBDs offer better circadian tunability than three-primary ones. With the discovery of intrinsically photosensitive retinal ganglion cells (ipRGCs), the circadian effect of lighting has drawn great attention from the community. The optimization of spectral power distribution (SPD) in laser-based displays (LBDs) has gained substantial interest. In this paper, we propose a comprehensive spectral optimization method for both three-primary and four-primary LBDs, tailored for users across different age groups (1–100 years old). By employing a Gaussian spectral model and genetic algorithm (GA) optimization under constraints such as color gamut coverage (Rec. 2020) and correlated color temperature (CCT), we identify optimal SPDs that minimize or maximize melanopic efficacy of luminous radiation (MELR). The results reveal that the MELR decreases with age and increases with CCT, and that four-primary LBDs offer higher circadian tunability than three-primary LBDs. These findings establish a framework for the design of age-adaptive healthy display technologies that balance circadian impact, visual performance, and photobiological safety.