Light and sleep – or why we (usually) sleep at night
Sleep usually happens at night. For our ancestors, there were very practical reasons for this. Artificial light was expensive, high maintenance, and not without danger. Also, it was too dim …
Sleep usually happens at night. For our ancestors, there were very practical reasons for this. Artificial light was expensive, high maintenance, and not without danger. Also, it was too dim …
In today’s world, LED displays are omnipresent. We use them for computers, smart phones, e-book readers and television. And we use all these appliances until late at night, often …