Someone has apparently crunched the numbers and estimated that more than 100 million birds are killed every year due to collisions with glass surfaces – not to mention the untold numbers of beverages spilt by surprised people as a bird slams into a nearby window.
Birds see the tree or sky reflected in a window or the environment behind the glazing, but not the glass itself. German company Glaswerke Arnold (or Arnold Glass) has come up with a simple way to prevent these collisions by producing a glass that appears normal to humans but is visible to birds.
Working on the principle that birds possess the ability to see light in the ultraviolet spectrum, the company’s Ornilux Bird-Protection Glass borrows a trick from orb-web spiders that protect their laboriously woven webs from birds flying through them with a special UV-reflecting silk. Recognizing this, the company developed the glass with a patterned UV reflective coating that makes it visible to birds while maintaining transparency to the human eye.