A new optical prescription for automobile side-view mirrors
may eliminate the dreaded "blind spot" in traffic without distorting
the perceived distance of cars approaching from behind. As described in a paper
published today in the Optical Society’s (OSA) journal Optics Letters, objects
viewed in a mirror using the new design appear larger than in traditional
side-view mirrors, so it’s easier to judge their following distance and speed.
Today's motor vehicles in the United States use two
different types of mirrors for the driver and passenger sides. The driver's
side mirror is flat so that objects viewed in it are undistorted and not
optically reduced in size, allowing the operator to accurately judge an
approaching-from-behind vehicle's separation distance and speed. Unfortunately,
the optics of a flat mirror also create a blind spot, an area of limited vision
around a vehicle that often leads to collisions during merges, lane changes, or
turns. The passenger side mirror, on the other hand, possesses a spherical
convex shape. While the small radius of curvature widens the field of view, it
also causes any object seen in it to look smaller in size and farther away than
it actually is.