When early humans discovered how to harness fire, they were able to push back against the nightly darkness that enveloped them. With the invention and widespread adoption of electricity, it became easier to separate heat from light, work through the night, and illuminate train cars to highways. In recent years, old forms of electric light generation such as halogen lightbulbs have given way to more energy efficient alternatives, further cheapening the costs to brighten our homes, workplaces, and lives generally.
Click here for original story, Identifying a new, cleaner source for white light
Source: Phys.org