Sun worshippers need a better way of recording their level of exposure to UV light, says Martin Hill of Chalfont St Giles, Buckinghamshire, UK. In patent GB 2383931 he suggests a UV-sensitive patch that sticks to the skin like a temporary tattoo. The patch changes colour when the sun is dangerously strong, and for people who miss this warning it also has a decorative chart printed with inks that act as UV filters of various strengths.
When the patch is removed, the skin underneath will be tanned in the shape of the chart. Matching the degree of tanning on other…
