The Indian government may use 3D paintings as virtual speed breakers ( 减速带 ) on major highways and roads, in order to check speeding and careless driving, and finally make its deadly roads a little safer. “We are trying out 3D paintings used as virtual speed breakers to avoid unnecessary requirements of speed breakers,” India’s transport minister Nitin Gadkari wrote. The optical illusions ( 视觉错觉 ) are supposed to encourage drivers to slow down automatically. Earlier, India had ordered the removal of all speed breakers from highways, which are considered to be a safety hazard for high-speed vehicles. India has the highest number of road accident deaths in the world. According to the World Health Organisation, over 200,000 people are killed by road accidents. The use of optical illusions as speed breakers was first pioneered in the American city of Philadelphia in 2008, as part of a campaign against speeding motorists. The technique has also been tried out in China to create floating 3D crossings. In India, cities such as Ahmedabad and Chennai have already experimented with 3D zebra crossings in the last one year. In Ahmedabad for instance, a mother and her daughter, both artists, have painted 3D crosswalks in the first few months of 2016. The artists say their motto is “to increase the attention of drivers”, and that the concept has been successfully tested in accident-prone zones on a highway. However, critics argue that once drivers know that these speed breakers are visual illusions, they may ignore them. Others also point out that India’s decision does not consider the safety of a large number of pedestrians. In the end, the new policy may be just one step towards improving road safety. 1 . Why are 3D paintings used on main highways and roads?