There's growing concern among experts that the proliferation of glowing gadgets like computers may fool your brain into thinking that it's still daytime after the sun has gone down. Exposure during the night can disturb sleep patterns and exacerbate insomnia.
Such concerns are not new -- Thomas Edison may have created these problems when he invented the light bulb. But the problem has grown worse thanks to the popularity of Apple's new slate computer, the iPad.
Many consumers use an iPad to read at night, and unlike paper books or e-book readers like the Amazon Kindle, which does not emit its own light, the iPad's screen shines light directly into your eyes from a relatively close distance.
According to CNN:
"That makes the iPad and laptops more likely to disrupt sleep patterns than, say, a television sitting across the bedroom or a lamp that illuminates a paper book, both of which shoot far less light straight into the eye, researchers said."