In this application perfect retroreflection is not desired, since the light would then be directed back into the headlights of an oncoming car rather than to the driver's eyes.
在这种应用中，完美的逆反射并不是想要的，因为这样的话，光就会径直地向驶来的车的车灯射去，而不是射入司机的眼睛。