While debates over privacy on and off the Internet rage, Japan has just come out with an ideal item for the privacy conscious: eyeglasses that block facial-recognition technology. The Privacy Visor, which was the brainchild of the government-affiliated National Institute of Informatics and an eyeglass manufacturer over the last two years. The Visor works by using patterns and angles on the lens that either reflect or absorb light, disrupting auto-focus to make faces undetectable.

According to Engadget, the new spectacles work with digital cameras as well as the cameras found in smartphones and tablets. The Wall Street Journal reports that Professor Isao Echizen, who led the research project, told Japan Real Time that the visor is the first product using this technology.

“We are often told not to unveil our personal information to others, but our faces are also a type of an ID,” he says. “There should be a way to protect that.” He adds that privacy-conscious users are meant to wear the Visor in crowded spaces, where they are more likely to have their photo taken unawares.

In tests, the glasses were able to block facial recognition 90 percent of the time. Although the lenses sport patterns, they aren’t disruptive enough for vision to keep wearers from walking. The Privacy Visor could be used for nefarious purposes since it would also prevent security cameras from recording faces, but Echizen responds that, “police investigations rely on other information as well to identify a person.”

Engadget reports that similar facial-recognition blocking eyeglasses based on infrared LED technology were shown in prototype at Mobile World Congress. The Privacy Visor is slated to be available in June 2016 and cost about ¥30,000 (about $240).