Like many expecting parents, Tracy Mizraki Kraft in Portola Valley, Calif., worried about how her newborn would sleep. So she paid attention when her doctor handed her a light bulb that he said would help her son do just that.

The small amber bulb, called Sleepy Baby, seemed to work well, she said, creating a soothing environment for Leo, now 16 months, as he drifted off to sleep.

For Ms. Mizraki Kraft, the bulb’s appeal was self-preservation. But it is part of a technological revolution coming to homes, offices, hotels and schools through lighting designed to undo the ill effects of artificial light — both overhead and on screen — and help regulate sleep, alertness and even people’s moods.

“Lighting is really not about a fixture in the ceiling anymore,” said Mariana Figueiro, who leads light and health research at the Lighting Research Center of Rensselaer Polytechnic Institute. “It’s about delivering individualized light treatments to people.”