Ever heard of the circadian rhythm—aka. your 24-hour wake-sleep cycle controlled by an internal clock in your system? This rhythm basically determines when your body should get some shut-eye and when you should get to grinding in the morning. External stimuli (i.e., darkness and daylight) from the environment stimulate receptors in your eyes to influence the circadian rhythm.
Drawing on the findings of several studies, the effects of blue light on sleep patterns and quality of sleep are twofold. On the one hand, I found a bunch of studies suggesting that the right exposure to blue light could help improve your performance and mood. On the darker side of the narrative, blue light also appears to be a major culprit to your diminishing quality and quantity of sleep.