Now, read in sunlight on smartphone

Washington: Inspired by the nano structures found on moth eyes, scientists have developed a new antireflection film that could allow people to read from their smartphones and tablets even in bright sunlight.

The film exhibits a surface reflection of just 0.23 per cent, much lower than the iPhone’s surface reflection of 4.4 per cent, for example. Reflection is the major reason it is difficult to read a phone screen in bright sunlight, as the strong light reflecting off the screen’s surface washes out the display.

“Using our flexible antireflection film on smartphones and tablets will make the screen bright and sharp, even when viewed outside,” said Shin-Tson Wu from the University of Central Florida in the United States.

“In addition to exhibiting low reflection, our nature- inspired film is also scratch resistant and self-cleaning, which would protect touch screens from dust and fingerprints,” said Wu, who led the study published in the journal Optica.

The new film contains tiny uniform dimples, each about 100 nanometres in diameter (about one-thousandth of the width of a human hair). The coating can also be used with flexible display applications such as phones with screens that fold like a book, which are expected to hit the market as soon as next year.

Many of today’s smartphones use a sensor to detect bright ambient light and then boost the screen’s brightness level enough to overcome the strong surface reflection. Although this type of adaptive brightness control can help improve readability, it also drains battery power. Other methods for solving the sunlight visibility problem have proved difficult to implement.