The devices and methods of the invention ameliorate age-related losses of night time visual acuity by constricting the pupil with a directionally focused, low-power light source close to the eye that does not impair vision by reflecting off the internal glass surfaces of the windshield and windows. Preferred devices and methods include means for adjusting the brightness of the light source and the distance and angular orientation between the light source and the eye. Particularly preferred devices and methods provide means to fix the light source in relation to the eye so that effectiveness is not diminished when the driver turns his or her head.