Most of us are aware of the dangers surrounding the amount of time we spend in the sun. Although we rely on exposure to sunlight to provide us with vitamin D, a lack of protection from harmful ultraviolet (UV) rays can lead to skin cancer. The UVA+B Sunfriend is designed to let users walk that fine line between too little and too much sun without the use of sunscreen.

The Sunfriend is not the first UV-measuring wrist band we've looked at, but devices such as the UVeBand measure the period of effectiveness of sunscreen based on cumulative UV exposure and prompt users to reapply sunscreen when approaching its UV absorption threshold. Because sunscreen blocks UVB rays, which are beneficial in moderation, as well as UVA rays, the team behind the UVA+B Sunfriend aim to let people tread the right side of that exposure line without using sunscreen.

The goal is to counter an increase in vitamin D deficiency, while curbing skin cancer rates by promoting outdoor activity within a recommended range of sun exposure. The company says, "We designed the SunFriend to help people optimize their vitamin D and reduce the incidence of skin cancer simultaneously."

The waterproof wristband contains patented, NASA-inspired UV sensors with LED indicators that light up as UV exposure accumulates, before flashing once the safe limit has been reached. The user sets the device to their skin tone and sensitivity and it then constantly measures both direct and reflected UV exposure.

The concept gained traction after inventors Shahid Aslam and Karin Edgett won best Consumer Product and Most Popular Vote awards at the 2011 Create the Future contest, run by NASA TechBriefs. Aslam and Edgett then put together a team of engineers, scientists and marketers and set about testing prototypes with the aim of developing UVA+B Sunfriend as a commercial product.

The Indiegogo campaign was launched on October 3 and at the time of writing has raised over US$17,000 of its $25,000 goal. A pledge of $45 ($10 of which goes to the Vitamin D Council) will land you a UVA+B Sunfriend of your own. It's worth noting that this is a Flexible Funding campaign, so the company will be collecting all money pledged even if the goal is not reached.

You can hear from the developers in the video below.

Source: Sunfriend