Whenever a motor vehicle is being operated on a highway or shoulder adjacent thereto during the times specified by law, the driver shall use a distribution of light, or composite beam, directed high enough and of sufficient intensity to reveal persons and vehicles at a safe distance in advance of the vehicle, subject to the requirement that whenever the driver of a vehicle approaches an oncoming vehicle within five hundred feet, such driver shall use a distribution of light or composite beam so aimed that the glaring rays are not projected into the eyes of the oncoming driver.